Code of Federal Regulations, 2012 CFR
2012-01-01
... which are mature but not soft or overripe, well formed and which are free from decay, bacterial spot, cuts which are not healed, growth cracks, hail injury, scab, scale, split pits, worms, worm holes, leaf...
Code of Federal Regulations, 2013 CFR
2013-01-01
... which are free from decay, growth cracks, cuts which are not healed, worms, worm holes, and free from damage caused by bruises, dirt, or other foreign material, bacterial spot, scab, scale, hail injury, leaf...
Code of Federal Regulations, 2014 CFR
2014-01-01
... which are free from decay, growth cracks, cuts which are not healed, worms, worm holes, and free from damage caused by bruises, dirt, or other foreign material, bacterial spot, scab, scale, hail injury, leaf...
Code of Federal Regulations, 2010 CFR
2010-01-01
... which are mature but not soft or overripe, well formed and which are free from decay, bacterial spot, cuts which are not healed, growth cracks, hail injury, scab, scale, split pits, worms, worm holes, leaf...
Code of Federal Regulations, 2011 CFR
2011-01-01
... which are mature but not soft or overripe, well formed and which are free from decay, bacterial spot, cuts which are not healed, growth cracks, hail injury, scab, scale, split pits, worms, worm holes, leaf...
Yadav, Arun K; Temjenmongla
2011-10-01
The leaves of Houttuynia cordata Thunb. (Saururaceae) are considered to have anthelmintic properties in the traditional medicine of Naga tribes in Northeast India and, therefore, are used by the natives to treat the intestinal worm infections. In the present study, the anticestodal activity of H. cordata leaf extract was investigated against Hymenolepis diminuta, a zoonotic cestode, in experimentally infected albino rats. For the assessment of anticestodal efficacy, the eggs per gram (EPG) of faeces counts and worm loads of animals were monitored following treatment with 200, 400 and 800 mg/kg p.o. doses of leaf extract to different groups of rats harbouring larval, immature and mature H. diminuta infections. The efficacy of the extract was found to be dose-dependent (P < 0.05). Further, the extract showed its maximum efficacy against the mature Hymenolepis worms. In this case, the 800 mg/kg dose of extract significantly reduced (P < 0.001) the EPG counts of animals by 57.09% and worm load by 75.00%, at post-treatment. In comparison, the reference drug praziquantel at 5 mg/kg showed a reduction in the EPG counts and worm load of experimental animals by 80.37 and 87.50%, respectively. These findings indicate that leaves of H. cordata possess significant anticestodal property and provide a rationale for their use in traditional medicine as an anthelmintic.
Blazer, V.S.; Waldrop, T.B.; Schill, W.B.; Densmore, Christine L.; Smith, D.
2003-01-01
Eastern Tubifex tubifex worms were exposed to Myxobolus cerebralis spores at 9, 13, 17, and 20 C in 1-L jars that contained sand, mud, or leaf litter as substrata. Beginning 60 days after exposure, water from each jar was filtered daily and examined for the presence of waterborne triactinomyxon spores (TAMs). On discovering a single TAM from an experimental jar, 48 T. tubifex worms from that jar were placed individually into 24-well plates. Spores released from individual infected T. tubifex worms were quantified to determine the first day of TAM release from infected worms, the infection rate, the total number of TAMs released per worm, and the duration of release. No TAMs were found in any of the jars incubated at 20 C or in uninfected, control worms at any temperature. The total number of TAMs released by infected worms in mud and sand was highest at 13 C compared with other temperatures. Infection rates among individual worms increased with temperature between 9 and 17 C. Higher temperatures (up to 17 C) induced earlier TAM releases among infected worms, and substratum did not influence this production parameter. The average duration of TAM release decreased as the temperature increased from 9 to 17 C, and there was a significant effect of substratum in the groups maintained at 13 and 17 C. In all temperature treatments between 9 and 17 C, the duration of release was least in the worms maintained in leaf litter, as was the total number of TAMs released during the experimental period and the median number of TAMs per production day.
Marie-Magdeleine, C; Udino, L; Philibert, L; Bocage, B; Archimede, H
2014-02-01
This study was carried out to evaluate the in vitro effect of Musa x paradisiaca stem and leaf against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and/or dichloromethane) of Musa x paradisiaca stem and leaf were tested in vitro on four developmental stages of H. contortus using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI) and adult worm motility assay (AWM). The highly significant (P<0.0001) ability to stop larval development (inhibition >67% for each extract) and the negative effect of the dichloromethane extract of leaf on adult worm motility (43% of inhibition of motility after 24h of incubation) compared to the negative controls, suggest anthelmintic properties of Musa x paradisiaca stem and leaf against H. contortus. The active principles responsible for the activity could be secondary metabolites such as terpenoid and flavonoid compounds present in the leaf and stem of the plant. Copyright © 2013 Elsevier Ltd. All rights reserved.
Effect of sericea lespedeza leaf meal pellets on adult female Haemonchus contortus in goats.
Kommuru, D S; Whitley, N C; Miller, J E; Mosjidis, J A; Burke, J M; Gujja, S; Mechineni, A; Terrill, T H
2015-01-15
Sericea lespedeza (SL; Lespedeza cuneata) is a perennial warm-season forage rich in condensed tannins (CT) that has been reported to have anthelmintic activity against small ruminant gastrointestinal nematodes (GIN), particularly Haemonchus contortus, a highly pathogenic blood-feeder, but the mechanism of action of CT against H. contortus is not clearly understood. An experiment with young goats was designed to study the effect of SL leaf meal pellets on (1) a mature H. contortus infection, and (2) the surface appearance of adult H. contortus female worms. Thirty-six female and castrated male Boer crossbred goats artificially infected with H. contortus larvae were fed 75% SL leaf meal pellets or alfalfa pellets (18 goats/treatment group) in a 28-day confinement feeding trial. Fecal and blood samples were collected weekly for fecal egg count (FEC) and packed cell volume (PCV) determination, respectively, and all goats were slaughtered at the end of the trial for adult GIN recovery and counting. Five adult female H. contortus were recovered from the abomasum of two goats from each treatment group and from a prior study in which 75% and 95% SL leaf meal pellets or a commercial feed pellet were group-fed to grazing goats (270 days old, Spanish males, 10/treatment group) at 0.91 kg/head/d for 11 weeks. Adult GIN collected were fixed and examined for evidence of surface damage using scanning electron microscopy. Feeding 75% SL pellets to young goats in confinement reduced (P<0.05) FEC compared with control animals, while total worm numbers and PCV were not influenced by treatment. Three out of the 5 adult H. contortus recovered from SL treatment goats in the confinement feeding trial had cuticular surface damage, while no damage was observed on worms from the control group. All five worms observed from both SL treatments in the grazing study showed a shrunken, disheveled cuticular surface, whereas this was not observed on worms from control animals. Overall, this work suggests that a possible mechanism of action of SL against female H. contortus in the animal's abomasum is a direct action of CT on the cuticle of the worm. Copyright © 2014 Elsevier B.V. All rights reserved.
Detrimental Influence of Invasive Earthworms on North American Cold-Temperate Forest Soils
ERIC Educational Resources Information Center
Enerson, Isabel
2012-01-01
The topic of invasive earthworms is a timely concern that goes against many preconceived notions regarding the positive benefits of all worms. In the cold-temperate forests of North America invasive worms are threatening forest ecosystems, due to the changes they create in the soil, including decreases in C:N ratios and leaf litter, disruption of…
Gogoi, Shyamalima; Yadav, Arun K.
2016-01-01
Background: Leaves of Caesalpinia bonducella (L.) Roxb. have been traditionally used as an herbal remedy to treat the intestinal helminthic infections in traditional medicine of India. Aim: This study was undertaken to evaluate the potential in vitro and in vivo anthelmintic effects of C. bonducella leaf extract against Syphacia obvelata (Nematoda) and Hymenolepis diminuta (Cestoda). Materials and Methods: The in vitro anthelmintic activity of the extract was investigated on adult worms of S. obvelata (Nematoda) and H. diminuta (Cestoda) in terms of physical motility and mortality of parasites. The in vivo study was performed in H. diminuta-rat model and S. obvelata-mice model, by monitoring the egg per gram of feces count and worm count of animals following the treatment with different doses of plant extract. Results: The study recorded significant and dose-dependent anthelmintic effects of the extract on both the parasites. In the in vitro study, 30 mg/ml concentration of extract caused mortality of H. diminuta in 2.5 ± 0.2 h and S. obvelata in 3.57 ± 0.16 h. In the in vivo study, the extract showed a comparatively better efficacy on S. obvelata, where its 800 mg/kg dose revealed 93% reduction of worm load in mice, as compared to 85% worm load reduction of H. diminuta in rats. Conclusions: The findings suggest that leaf extract of C. bonducella possesses significant anthelmintic effects and supports its use as an anthelmintic in traditional medicine. This appears to be the first report of in vivo anthelmintic activity of C. bonducella against these parasites. PMID:27757275
Worm Gear With Hydrostatic Engagement
NASA Technical Reports Server (NTRS)
Chaiko, Lev I.
1994-01-01
In proposed worm-gear transmission, oil pumped at high pressure through meshes between teeth of gear and worm coil. Pressure in oil separates meshing surfaces slightly, and oil reduces friction between surfaces. Conceived for use in drive train between gas-turbine engine and rotor of helicopter. Useful in other applications in which weight critical. Test apparatus simulates and measures some loading conditions of proposed worm gear with hydrostatic engagement.
Joshi, B R; Kommuru, D S; Terrill, T H; Mosjidis, J A; Burke, J M; Shakya, K P; Miller, J E
2011-05-31
Effect of sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don.] leaf meal feeding was evaluated in two experiments in indoor reared goats with experimental infection of Haemonchus contortus larvae. In the first experiment, ten 8-10 month old male Spanish and Alpine cross kids pair matched for body weight and age were fed SL or bermudagrass [BG; Cynodon dactylon (L.) Pers.] hay one week before infection and were infected with 5000 H. contortus L(3). The animals were maintained on the same diet for the remaining period and were slaughtered 28 days post-infection (DPI) to determine the establishment of incoming infective larvae. Goats fed SL had lower establishment (P<0.05) of H. contortus larvae than that of the control goats fed BG hay. In the second experiment, twenty-five 8-10 months old male Alpine cross, Saanen, Nubian×Saanen and Spanish kids reared in confinement on BG were experimentally infected with 5000 H. contortus L(3). On 35 DPI, the animals were allocated to two groups after blocking by fecal egg count (FEC), and one group was fed SL leaf meal (n=13), and another control group remained on BG (n=12). Four goats/group were slaughtered successively on days 7, 14, and 28 days post SL feeding, except on day 7, when five SL fed goats were slaughtered. Fecal egg counts and blood packed cell volume (PCV) were measured at weekly intervals and worm count, female worm fecundity, worm length and mucosal eosinophils, mast cells and globule leucocytes were measured after slaughter. Goats fed SL had a lower FEC (P<0.05) one week after feeding, as compared to those fed on BG, and the values remained at low level thereafter. Similarly, PCV was also significantly affected by feeding (P<0.01), and feeding and time interaction (P<0.05). However, worm burden, female worm fecundity, parasite length, and mucosal inflammatory cell count were similar between the groups. Feeding SL reduced the establishment of infective larvae and FEC of H. contortus in experimental studies and this plant could be used for biological control of parasite infection under field conditions to limit the harmful effects of the parasites in goats. Copyright © 2010 Elsevier B.V. All rights reserved.
Lifespan-on-a-chip: microfluidic chambers for performing lifelong observation of C. elegans†
Hulme, S. Elizabeth; Shevkoplyas, Sergey S.; McGuigan, Alison P.; Apfeld, Javier; Fontana, Walter
2011-01-01
This article describes the fabrication of a microfluidic device for the liquid culture of many individual nematode worms (Caenorhabditis elegans) in separate chambers. Each chamber houses a single worm from the fourth larval stage until death, and enables examination of a population of individual worms for their entire adult lifespans. Adjacent to the chambers, the device includes microfluidic worm clamps, which enable periodic, temporary immobilization of each worm. The device made it possible to track changes in body size and locomotion in individual worms throughout their lifespans. This ability to perform longitudinal measurements within the device enabled the identification of age-related phenotypic changes that correlate with lifespan in C. elegans. PMID:20162234
USDA-ARS?s Scientific Manuscript database
The Spodoptera littoralis multiple nucleopolyhedrovirus (SpliMNPV), a pathogen of the Egyptian cotton leaf worm Spodoptera littoralis, was subjected to sequencing of its entire DNA genome and bioassay analysis comparing its virulence to that of other baculoviruses. The annotated SpliMNPV genome of...
Carrara, V S; Vieira, S C H; de Paula, R G; Rodrigues, V; Magalhães, L G; Cortez, D A G; Da Silva Filho, A A
2014-09-01
Dichloromethane and aqueous fractions from leaves and stems of Piper arboreum Aubl., P. aduncum L., P. amalago L., P. crassinervium H.B. & K., P. diospyrifolium Kunth, P. hispidum Sw. and P. xylosteoides (Kunth) Steud. were tested against adult worms of Schistosoma mansoni. The in vitro activity was evaluated in terms of mortality, number of separated worms and number of worms with reduced motor activity. Most dichloromethane fractions from all Piper species showed moderate schistosomicidal activity, but aqueous fractions were not active. The dichloromethane fraction of P. amalago leaves (at 100 μg/ml) showed the highest activity, resulting in worm mortality, the separation of worm pairs and reduced motor activity. Chromatographic fractionation of the dichloromethane fraction of P. amalago leaves led to the isolation of its major compound, which was also tested against adults of S. mansoni. The isolated piperamide N-[7-(3',4'-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl] pyrrolidine, at 100 μ m, resulted in the mortality of all adult worms after 24 h of incubation. The findings suggest that species of Piper are potential sources of schistosomicidal compounds.
Khumrungsee, N; Pluempanupat, W; Kainoh, Y; Saguanpong, U; Bullangpotin, V
2010-01-01
This study explored the insecticidal effects of Thai botanical, senescent leaf Jatropha gossypifolia extracts on second instar Spodoptera exigua larvae by the dipping method and topical sprayer method. The leaf crude extract was extracted using Soxhlet apparatus with ethyl acetate as solvent. The leaf crude extracts showed insecticidal activity with a LC50 of 6182 ppm at 24 hours after treatment. In addition, this research was observed its toxicity to worm parasitoid, Meteorus pulchricornis by contact method. The result shows 60 percent mortality of this parasitoid species at dose up to 40,000 ppm. Thus, Jatropha gossypifolia leaf crude extracts can be as alternative IPM control tool for Spodoptera exigua which friendly to benefit insect such as Meteorus pulchricornis.
Osman, Gamal H.; Assem, Shireen K.; Alreedy, Rasha M.; El-Ghareeb, Doaa K.; Basry, Mahmoud A.; Rastogi, Anshu; Kalaji, Hazem M.
2015-01-01
Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica. PMID:26658494
Complete mitochondrial genome of yellow meal worm(Tenebrio molitor)
LIU, Li-Na; WANG, Cheng-Ye
2014-01-01
The yellow meal worm(Tenebrio molitor L.) is an important resource insect typically used as animal feed additive. It is also widely used for biological research. The first complete mitochondrial genome of T. molitor was determined for the first time by long PCR and conserved primer walking approaches. The results showed that the entire mitogenome of T. molitor was 15 785 bp long, with 72.35% A+T content [deposited in GenBank with accession number KF418153]. The gene order and orientation were the same as the most common type suggested as ancestral for insects. Two protein-coding genes used atypical start codons(CTA in ND2 and AAT in COX1), and the remaining 11 protein-coding genes started with a typical insect initiation codon ATN. All tRNAs showed standard clover-leaf structure, except for tRNASer(AGN), which lacked a dihydrouridine(DHU) arm. The newly added T. molitor mitogenome could provide information for future studies on yellow meal worm. PMID:25465087
Complete mitochondrial genome of yellow meal worm (Tenebrio molitor).
Liu, Li-Na; Wang, Cheng-Ye
2014-11-18
The yellow meal worm (Tenebrio molitor L.) is an important resource insect typically used as animal feed additive. It is also widely used for biological research. The first complete mitochondrial genome of T. molitor was determined for the first time by long PCR and conserved primer walking approaches. The results showed that the entire mitogenome of T. molitor was 15 785 bp long, with 72.35% A+T content [deposited in GenBank with accession number KF418153]. The gene order and orientation were the same as the most common type suggested as ancestral for insects. Two protein-coding genes used atypical start codons (CTA in ND2 and AAT in COX1), and the remaining 11 protein-coding genes started with a typical insect initiation codon ATN. All tRNAs showed standard clover-leaf structure, except for tRNA(Ser) (AGN), which lacked a dihydrouridine (DHU) arm. The newly added T. molitor mitogenome could provide information for future studies on yellow meal worm.
Vermicompost derived from different feedstocks as a plant growth medium.
Warman, P R; Anglopez, M J
2010-06-01
This study determined feedstock effects on earthworm populations and the quality of resulting vermicomposts produced from different types of feedstocks using different vermicomposting durations. Feedstock combinations (Kitchen Paper Waste (KPW), Kitchen Yard Waste (KYW), Cattle Manure Yard Waste (CMY)), three durations of vermicomposting (45, 68 or 90 days), and two seed germination methods (with two concentrations of vermicompost) for radish, marigold and upland cress, served as the independent variables. The worms (Eisenia fetida) doubled their weight by day 68 in KPW and CMY vermicomposts and day 90 KPW vermicompost produced the greatest weight of worms. The direct seed germination method (seeding into soil or vermicompost-soil mixtures) indicated that KPW and KYW feedstocks decreased germination compared to the control, even in mature vermicompost. Seed germination was greater in the water extract method; however, most of the vermicompost extracts suppressed germination of the three seed species compared to the water controls. Vermicomposts from all three feedstocks increased leaf area and biomass compared to the control, especially in the 10% vermicompost:soil mix. Thus, seed germination and leaf area or plant biomass for these three species are contrasting vermicompost quality indicators. (c) 2010 Elsevier Ltd. All rights reserved.
Palmieri, J R; Ratiwayanto, S; Masbar, S; Tirtokusumo, S; Rusch, J; Marwoto, H A
1985-09-01
Blood from 9 humans, 6 domestic cats (Felis domesticus), and 5 silvered leaf monkeys (Presbytis cristatus) from South Kalimantan (Borneo), Indonesia, with known filarial infections was examined for determination ofacid phosphatase activity of the microfilarae (mff). The findings suggest 1) that Brugia parasites from domestic cats and silvered leaf monkeys can be speciated by acid phosphatase activity and that speciation by acid phosphatase assay corresponds to that based upon adult worm morphology and 2) that Brugia mff from humans have acid phosphatase activity characteristic of that of B. pahangi microfilariae from cat and monkey. Thus B. pahangi may infect man in South Kalimantan.
Parental effects on the larval performance of a tapeworm in its copepod first host.
Benesh, D P
2013-08-01
Parents can influence the phenotype of their offspring through various mechanisms, besides the direct effect of heredity. Such parental effects are little explored in parasitic organisms, perhaps because in many parasites, per capita investment into offspring is low. I investigated whether parental identity, beyond direct genetic effects, could explain variation in the performance of the tapeworm Schistocephalus solidus in its first intermediate host, a copepod. I first determined that two breeding worms could be separated from one another after ~48 h of in vitro incubation and that the isolated worms continued producing outcrossed eggs, that is, rates self-fertilization did not increase after separation. Thus, from a breeding pair, two sets of genetically comparable eggs can be collected that have unambiguous parental identities. In an infection experiment, I found that the development of larval worms tended to vary between the two parental worms within breeding pairs, but infection success and growth rate in copepods did not. Accounting for this parental effect decreased the estimated heritability for development by nearly half. These results suggest that larval performance is not simply a function of a worm's genotype; who mothered or fathered an offspring can also affect offspring fitness, contradicting the perhaps naïve idea that parasites simply produce large quantities of uniformly low-quality offspring. © 2013 The Author. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.
Anthelmintic efficacy of Clerodendrum viscosum on fowl tapeworm Raillietina tetragona.
Nandi, Suranjana; Ukil, Bidisha; Roy, Saptarshi; Kundu, Suman; Lyndem, Larisha Mawkhlieng
2017-12-01
Clerodendrum viscosum Vent. (Verbenaceae) is a shrub, widely used amongst the natives of India against various diseases. Crude extract of the plant was tested in vitro on a tapeworm Raillietina tetragona Molin (Davaineidae) to evaluate its potential anthelmintic efficacy and ultrastructural changes in the parasite. Parasites were exposed to different concentrations of ethanolic leaf extract (10-80 mg/mL) and praziquantel (0.0005-0.005 mg/mL) and incubated in phosphate-buffered saline (PBS). The pH was 7.4 at 37 °C, while one set of worms was incubated only with PBS as a control. Permanent immobilization of worms was determined visually when no motility occurred on physically disturbing them. The parasites exposed to high concentrations of leaf extract and praziquantel treatments were processed for histological and electron microscopic studies, as these concentrations took the least time for paralysis and death to occur. With an increase in the concentration of the leaf extract from 10 to 80 mg/mL and praziquantel from 0.0005 to 0.005 mg/mL, the time for the onset of paralysis and death was shortened. The treated parasites lost their spontaneous movement rapidly followed by death. Electron microscopic observations revealed disruptions in the tegument and parenchymal layer, accompanied by deformities in cell organelles. Extensive structural alterations in the tegument indicate that the plant-derived components cause permeability changes in the parasite leading to paralysis and subsequent death. These observations suggest that phytochemicals present in C. viscosum have vermifugal or vermicidal activity, and thus may be exploited as alternative chemotherapeutic agents.
Hodgkin, Jonathan; Félix, Marie-Anne; Clark, Laura C.; Stroud, Dave; Gravato-Nobre, Maria J.
2013-01-01
Summary The nematode Caenorhabditis elegans has been much studied as a host for microbial infection. Some pathogens can infect its intestine [1, 2], while others attack via its external surface [1, 3–6]. Cultures of Caenorhabditis isolated from natural environments have yielded new nematode pathogens, such as microsporidia and viruses [7, 8]. We report here a novel mechanism for bacterial attack on worms, discovered during investigation of a diseased and coinfected natural isolate of Caenorhabditis from Cape Verde. Two related coryneform pathogens (genus Leucobacter) were obtained from this isolate, which had complementary effects on C. elegans and related nematodes. One pathogen, Verde1, was able to cause swimming worms to stick together irreversibly by their tails, leading to the rapid formation of aggregated “worm-stars.” Adult worms trapped in these aggregates were immobilized and subsequently died, with concomitant growth of bacteria. Trapped larval worms were sometimes able to escape from worm-stars by undergoing autotomy, separating their bodies into two parts. The other pathogen, Verde2, killed worms after rectal invasion, in a more virulent version of a previously studied infection [6]. Resistance to killing by Verde2, by means of alterations in host surface glycosylation, resulted in hypersensitivity to Verde1, revealing a trade-off in bacterial susceptibility. Conversely, a sublethal surface infection of worms with Verde1 conferred partial protection against Verde2. The formation of worm-stars by Verde1 occurred only when worms were swimming in liquid but provides a striking example of asymmetric warfare as well as a bacterial equivalent to the trapping strategies used by nematophagous fungi [4]. PMID:24206844
Hodgkin, Jonathan; Félix, Marie-Anne; Clark, Laura C; Stroud, Dave; Gravato-Nobre, Maria J
2013-11-04
The nematode Caenorhabditis elegans has been much studied as a host for microbial infection. Some pathogens can infect its intestine, while others attack via its external surface. Cultures of Caenorhabditis isolated from natural environments have yielded new nematode pathogens, such as microsporidia and viruses. We report here a novel mechanism for bacterial attack on worms, discovered during investigation of a diseased and coinfected natural isolate of Caenorhabditis from Cape Verde. Two related coryneform pathogens (genus Leucobacter) were obtained from this isolate, which had complementary effects on C. elegans and related nematodes. One pathogen, Verde1, was able to cause swimming worms to stick together irreversibly by their tails, leading to the rapid formation of aggregated "worm-stars." Adult worms trapped in these aggregates were immobilized and subsequently died, with concomitant growth of bacteria. Trapped larval worms were sometimes able to escape from worm-stars by undergoing autotomy, separating their bodies into two parts. The other pathogen, Verde2, killed worms after rectal invasion, in a more virulent version of a previously studied infection. Resistance to killing by Verde2, by means of alterations in host surface glycosylation, resulted in hypersensitivity to Verde1, revealing a trade-off in bacterial susceptibility. Conversely, a sublethal surface infection of worms with Verde1 conferred partial protection against Verde2. The formation of worm-stars by Verde1 occurred only when worms were swimming in liquid but provides a striking example of asymmetric warfare as well as a bacterial equivalent to the trapping strategies used by nematophagous fungi. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.
Brito, D R B; Costa-Júnior, L M; Garcia, J L; Torres-Acosta, J F J; Louvandini, H; Cutrim-Júnior, J A A; Araújo, J F M; Soares, E D S
2018-03-15
Gastrointestinal nematodes (GINs) cause considerable economic losses in grazing goat herds. At present, GIN control cannot rely on conventional anthelmintic (AH) drugs because parasites have developed resistance against such drugs. Thus, alternative control methods are being sought to reduce the dependence on AH. Many tannin-rich plants exhibit AH activity and may be used as alternatives for GIN control. Mimosa caesalpiniifolia is a tannin-rich shrub consumed by small ruminants in Brazil. This study evaluated the in vivo AH effect of M. caesalpiniifolia leaf powder supplementation on GIN egg fecal excretion and worm burden in goats. Plant leaves were harvested, dried and ground to obtain a powder. Twenty-four castrated male goats, aged six to eight months, with a mean body weight of 15.0 ± 2.5 kg were used in the experiment. Animals were infected orally with 16,000 larvae comprising 50% Haemonchus spp., 41% Trichostrongylus spp. and 9% Oesophagostomum spp. Once the infection was patent, the goats were distributed into four groups of six animals. The control group received concentrate without condensed tannins (CTs) and did not receive any drench against GINs. The monepantel group received concentrate without CTs and were drenched once with monepantel. The other two groups received the M. caesalpiniifolia leaf powder in two periods of seven consecutive days (days 1-7 and 14-21), with one of the groups also receiving 10 g of polyethyleneglycol (PEG)/day. The animals were weighed weekly, and individual fecal eggs counts (FECs) were performed daily. After 28 days, the animals were humanly slaughtered, and the worm burden was estimated. Although live weight gain and FECs did not differ among the groups (P > 0.05), post-mortem worm counts showed a reduction in Haemonchus contortus adult worm burden (57.7%) in goats of the CT group compared to control goats (P < 0.05). The addition of PEG did not diminish AH activity in the CT + PEG group (66.9% reduction compared to the control). No AH effect against other GIN species was found. The result for the addition of PEG suggested that the observed AH activity was associated with plant secondary compounds, as opposed to CTs. As expected, no AH effect against Oesophagostomum columbianum was found for the monepantel group showed. Thus, feeding dry leaves of M. caesalpiniifolia represent a promising alternative for the control of GIN infections in goats. Copyright © 2018 Elsevier B.V. All rights reserved.
Architectural mutation and leaf form, for the palmate series.
White, D A
2005-07-21
Palmate leaf form occurs in both the ferns and angiosperms. The palmate leaf form, and its variants, is present in distantly separated clades within both ferns and angiosperms. There tend not to be intermediate forms which link these palmate leaves to other leaf forms within the taxonomic groups in question. The recurrence of homoplasious leaf forms in separate taxonomic groups could be a consequence of the algorithmic like mode of leaf growth. Leaves develop through the reiteration of modular units. It is probable that the homoplasious leaf forms in different taxa are derived independently through re-combinations of the parameters in the basic leaf form development algorithm.
Hansen, E P; Tejedor, A M; Thamsborg, S M; Alstrup Hansen, T V; Dahlerup, J F; Nejsum, P
2016-05-01
More than 400 million humans are estimated to be infected with the intestinal helminth parasite, Trichuris trichiura. The infection is chronic in nature and high-intensity infection can lead to colitis, anaemia, Trichuris Dysentery Syndrome and reduced cognitive performance. Single doses of 400 mg albendazole or 500 mg mebendazole (MBZ) are used in mass drug administration programmes, but this has been shown to be insufficient. In this study, worm expulsion dynamics are described after MBZ treatment, given as a multi-dose and single-dose treatment in two separate T. trichiura self-infection studies. Worm expulsion dynamics post-treatment showed a similar pattern regardless of the dose regime, with the first worms observed on day 2 and the last worms expelled on days 9 and 13 post-treatment. Establishment of a chronic infection was observed following the inefficient single-dose treatment. The prepatent period was 13-16 weeks in both studies and worms were found to have a lifespan of at least 1 year and 10 months. These self-infection studies provide key information on the chronicity of T. trichiura infections, expulsion dynamics after anthelmintic treatment and the prepatent period, as well as the fecundity of female worms, which was around 18,000 eggs/female per day.
Worm Algorithm simulations of the hole dynamics in the t-J model
NASA Astrophysics Data System (ADS)
Prokof'ev, Nikolai; Ruebenacker, Oliver
2001-03-01
In the limit of small J << t, relevant for HTSC materials and Mott-Hubbard systems, computer simulations have to be performed for large systems and at low temperatures. Despite convincing evidence against spin-charge separation obtained by various methods for J > 0.4t there is an ongoing argument that at smaller J spin-charge separation is still possible. Worm algorithm Monte Carlo simulations of the hole Green function for 0.1 < J/t < 0.4 were performed on lattices with up to 32x32 sites, and at temperature J/T = 40 (for the largest size). Spectral analysis reveals a single, delta-function sharp quasiparticle peak at the lowest edge of the spectrum and two distinct peaks above it at all studied J. We rule out the possibility of spin-charge separation in this parameter range, and present, apparently, the hole spectral function in the thermodynamic limit.
Modeling canopy-level productivity: is the "big-leaf" simplification acceptable?
NASA Astrophysics Data System (ADS)
Sprintsin, M.; Chen, J. M.
2009-05-01
The "big-leaf" approach to calculating the carbon balance of plant canopies assumes that canopy carbon fluxes have the same relative responses to the environment as any single unshaded leaf in the upper canopy. Widely used light use efficiency models are essentially simplified versions of the big-leaf model. Despite its wide acceptance, subsequent developments in the modeling of leaf photosynthesis and measurements of canopy physiology have brought into question the assumptions behind this approach showing that big leaf approximation is inadequate for simulating canopy photosynthesis because of the additional leaf internal control on carbon assimilation and because of the non-linear response of photosynthesis on leaf nitrogen and absorbed light, and changes in leaf microenvironment with canopy depth. To avoid this problem a sunlit/shaded leaf separation approach, within which the vegetation is treated as two big leaves under different illumination conditions, is gradually replacing the "big-leaf" strategy, for applications at local and regional scales. Such separation is now widely accepted as a more accurate and physiologically based approach for modeling canopy photosynthesis. Here we compare both strategies for Gross Primary Production (GPP) modeling using the Boreal Ecosystem Productivity Simulator (BEPS) at local (tower footprint) scale for different land cover types spread over North America: two broadleaf forests (Harvard, Massachusetts and Missouri Ozark, Missouri); two coniferous forests (Howland, Maine and Old Black Spruce, Saskatchewan); Lost Creek shrubland site (Wisconsin) and Mer Bleue petland (Ontario). BEPS calculates carbon fixation by scaling Farquhar's leaf biochemical model up to canopy level with stomatal conductance estimated by a modified version of the Ball-Woodrow-Berry model. The "big-leaf" approach was parameterized using derived leaf level parameters scaled up to canopy level by means of Leaf Area Index. The influence of sunlit/shaded leaf separation on GPP prediction was evaluated accounting for the degree of the deviation of 3-dimensional leaf spatial distribution from the random case. More specifically, we compared and evaluated the behavior of both models showing the advantages of sunlit/shaded leaf separation strategy over a simplified big-leaf approach. Keywords: canopy photosynthesis, leaf area index, clumping index, remote sensing.
Photodynamic inactivation using curcuminoids and Photogem on caenorhabditis elegans
NASA Astrophysics Data System (ADS)
Albuquerque, Yulli R.; Pratavieira, Sebastião.; Bagnato, Vanderlei S.; Inada, Natalia M.; Souza, Larissa M.; Afonso, Ana; de Souza, Clovis W. O.; Oliveira, Kleber T.; Anibal, Fernanda F.
2018-02-01
Resistance to various anthelmintic drugs is reported in many animals and can become a severe problem for human and animal health. In this study, Photogem® and three curcuminoids compounds (curcumin, demethoxycurcumin, bisdemethoxycurcumin) were used as photosensitizers in the photodynamic inactivation (PDI) in the helminth model Caenorhabditis elegans to investigate the ability of this procedure to worm life cycle. Initially, the presence and location of the photosensitizers in the worm's body were verified by fluorescence confocal microscopy. Curcumin was deposited in the digestive tract and Photogem® along the body of the animal in the incubation time of 12 hours with the photosensitizer. Subsequently, a PDI procedure using a LED device was performed to illuminate the worms treated with the photosensitizers. The worms were observed by optical microscopy until 48 hours after the PDI to verify the changes in motility, the presence of eggs and larvae and the number of live worms. Curcuminoids tested separately and in combination and two light doses of 30 J/m2 no changes were observed in the life cycle of the worm at concentrations of 2 mM and 1 mM. However, in treatment with Photogem® and a light dose of 100 J/m2 a reduction in motility and reproduction of the worm with 0.2 mg/mL was observed after 6 hours of exposure, in addition to the death of most worms at concentrations of 6, 4, and 2 mg/mL. We suggest, therefore, that photodynamic inactivation with Photogem® may present an anthelmintic effect against C. elegans, but there is a need for studies on helminths with parasitic activity.
Nissen, Sofie; Al-Jubury, Azmi; Hansen, Tina V A; Olsen, Annette; Christensen, Henrik; Thamsborg, Stig M; Nejsum, Peter
2012-08-13
The whipworms Trichuris trichiura and Trichuris suis in humans and pigs, respectively, are believed to be two different species yet closely related. Morphologically, adult worms, eggs and larvae of the two species are indistinguishable. The aim of this study was to examine the genetic variation of Trichuris sp. mainly recovered from natural infected pigs and humans. Worm material isolated from humans and pigs living in the same geographical region in Uganda were analyzed by PCR, cloning and sequencing. Measurements of morphometric characters were also performed. The analysis of the ITS-2 (internal transcribed spacer) region showed a high genetic variation in the human-derived worms with two sequence types, designated type 1 and type 2, differing with up to 45%, the type 2 being identical to the sequence found in pig-derived worms. A single human-derived worm showed exclusively the type 2-genotype (T. suis-type) and three cases of 'heterozygote' worms in humans were identified. However, the analysis showed that sympatric Trichuris primarily assorted with host origin. Sequence analysis of a part of the genetically conserved β-tubulin gene confirmed two separate populations/species but also showed that the 'heterozygote' worms had a T. suis-like β-tubulin gene. A PCR-RFLP on the ITS-2 region was developed, that could distinguish between worms of the pig, human and 'heterozygote' type. The data suggest that Trichuris in pigs and humans belong to two different populations (i.e. are two different species). However, the data presented also suggest that cross-infections of humans with T. suis takes place. Further studies on sympatric Trichuris populations are highly warranted in order to explore transmission dynamics and unravel the zoonotic potential of T. suis. Copyright © 2012 Elsevier B.V. All rights reserved.
[Efficacy evaluation of epsiprantel (Cestex) against Echinococcus mutilocularis in dogs and cats].
Eckert, J; Thompson, R C; Bucklar, H; Bilger, B; Deplazes, P
2001-01-01
Helminth-free dogs and cats were experimentally infected with protoscoleces of Echinococcus multilocularis and used in controlled trials for efficacy evaluation of the cestodicide epsiprantel. In two separate trials each 4 dogs were treated at day 20 post infection (p.i.) with average oral dosages of 5.1 (4.9-5.3) and 5.4 (5.2-5.8) mg/kg body weight (b.w.) epsiprantel, respectively, and necropsied at day 24 p.i. Among each 4 dogs of the two untreated control groups all animals were infected and had high intestinal worm burdens with averages of 33.575 and 100.725 E. multilocularis specimens per animal (individual worm burdens in group Ib 59,500-149,800, group IIb 20,500-43,200); in the two groups of treated dogs the average worm burdens were reduced by 99.6 and 99.9%. Among 8 treated dogs 4 were helminth-free, the other 4 had residual worm burdens (10-70 in 3 dogs, 1480 in 1 dog). In each 5 cats single oral treatments with average doses of 2.7 (2.7-2.8) and 5.5 (5.5-5.5) mg/kg b.w. epsiprantel were 100% effective against E. multilocularis 20 days p.i. and eliminated the worm burdens from all 10 animals. In the untreated group of 5 cats the average worm burden was 2864 per animal (individual worm burdens 20-6830). Side effects of the drug treatment were not observed. The results of the study show that in single therapeutic dosages recommended by the producer (dogs 5.5 mg, cats 2.75 mg/kg b.w.) epsiprantel eliminates E. multilocularis to over 99% or completely, but residual worm burdens may persist in some animals.
Genotypic relationships between Taenia saginata, Taenia asiatica and their hybrids.
Yamane, Kanako; Yanagida, Tetsuya; Li, Tiaoying; Chen, Xingwang; Dekumyoy, Paron; Waikagul, Jitra; Nkouawa, Agathe; Nakao, Minoru; Sako, Yasuhito; Ito, Akira; Sato, Hiroshi; Okamoto, Munehiro
2013-11-01
Partial sequences of the DNA polymerase delta (pold) gene from Taenia saginata-like adult worms were sequenced. Phylogenetic analysis revealed that pold gene sequences were clearly divided into two clades, differing from each other in five to seven nucleotides. There is little doubt that T. saginata and Taenia asiatica were once separated into two distinct taxa as has been concluded in previous studies. On the other hand, most of the adult worms, which were identified as T. asiatica using mitochondrial DNA, were homozygous for an allele that originated from the allele of T. saginata via single nucleotide substitution. These results indicate that most of the adult worms, which had been called T. asiatica, are not actually 'pure T. asiatica' but instead originated from the hybridization of 'pure T. saginata' and 'pure T. asiatica'.
de Saram, Paulu S. R.; Ressurreição, Margarida; Davies, Angela J.; Rollinson, David; Emery, Aidan M.; Walker, Anthony J.
2013-01-01
Cyclic AMP (cAMP)-dependent protein kinase/protein kinase A (PKA) is the major transducer of cAMP signalling in eukaryotic cells. Here, using laser scanning confocal microscopy and ‘smart’ anti-phospho PKA antibodies that exclusively detect activated PKA, we provide a detailed in situ analysis of PKA signalling in intact adult Schistosoma mansoni, a causative agent of debilitating human intestinal schistosomiasis. In both adult male and female worms, activated PKA was consistently found associated with the tegument, oral and ventral suckers, oesophagus and somatic musculature. In addition, the seminal vesicle and gynaecophoric canal muscles of the male displayed activated PKA whereas in female worms activated PKA localized to the ootype wall, the ovary, and the uterus particularly around eggs during expulsion. Exposure of live worms to the PKA activator forskolin (50 µM) resulted in striking PKA activation in the central and peripheral nervous system including at nerve endings at/near the tegument surface. Such neuronal PKA activation was also observed without forskolin treatment, but only in a single batch of worms. In addition, PKA activation within the central and peripheral nervous systems visibly increased within 15 min of worm-pair separation when compared to that observed in closely coupled worm pairs. Finally, exposure of adult worms to forskolin induced hyperkinesias in a time and dose dependent manner with 100 µM forskolin significantly increasing the frequency of gross worm movements to 5.3 times that of control worms (P≤0.001). Collectively these data are consistent with PKA playing a central part in motor activity and neuronal communication, and possibly interplay between these two systems in S. mansoni. This study, the first to localize a protein kinase when exclusively in an activated state in adult S. mansoni, provides valuable insight into the intricacies of functional protein kinase signalling in the context of whole schistosome physiology. PMID:23326613
Effectiveness of copper oxide wire particles for Haemonchus contortus control in sheep.
Knox, M R
2002-04-01
To assess the efficacy of copper oxide wire particles (COWP) for the control of H contortus infections in grazing sheep. In experiment 1, 40 worm-free Merino hoggets (11 to 12 months of age) were divided into four equal groups and allocated to separate 0.8 ha pasture plots. Two groups then received 2.5 g COWP whereas the other two groups were untreated. From 1 week after COWP treatment all lambs received a weekly infection of 2000 H contortus larvae. At week 8, six sheep from the untreated group were then allocated to two groups and treated with either 2.5 or 5.0 g of COWP to establish therapeutic efficacy of treatment. Experiment 2 followed a similar protocol but was conducted with 40 worm-free Merino lambs (3 to 4 months of age) and no assessment of therapeutic efficacy was made. In experiment 1 no significant difference in faecal worm egg counts was observed between treatments and faecal worm egg counts remained less than 3000 epg in all animals. Total worm counts were reduced by 37% by COWP treatment (P = 0.055). Both 2.5 g and 5.0 g doses of COWP at 8 weeks of infection reduced faecal worm egg counts by > 85% with the higher dose giving an earlier response to treatment. In experiment 2, faecal worm egg counts at 4 and 6 weeks were reduced by more than 90% in the COWP treated lambs and worm numbers were 54% lower after 6 weeks when all remaining untreated lambs had to be treated for haemonchosis. Mean faecal worm egg counts in the COWP lambs remained below 3500 epg and clinical disease did not develop in the majority of lambs before the end of the experiment at 10 weeks. Treatment with COWPs appears to have the potential to reduce establishment and worm fecundity of Haemonchus spp for an extended period and may offer livestock producers a supplementary means of reducing larval contamination of pasture particularly in areas where anthelmintic resistance is a problem and copper supplementation is likely to be beneficial.
Al-Sabi, Mohammad Nafi Solaiman; Hansen, Mette Sif; Chriél, Mariann; Holm, Elisabeth; Larsen, Gitte; Enemark, Heidi Larsen
2014-09-15
Spirocerca lupi causes formation of nodules that may transform into sarcoma in the walls of aorta, esophagus and stomach of infected canids. In February 2013, post mortem examination of a red fox (Vulpes vulpes) hunted in Denmark revealed the presence of several nodules containing adult worms of Spirocerca sp. in the stomach and the omentum. The nodules largely consisted of fibrous tissue with infiltration of mononuclear cells, neutrophilic granulocytes and macrophages with hemosiderin deposition. Parasitological examination by three copromicroscopic methods, sedimentation, flotation with saturated sugar-salt solution, and sieving failed to detect eggs of Spirocerca sp. in feces collected from the colon. This is the first report of spirocercosis in Denmark, and may have been caused by a recent introduction by migrating paratenic or definitive host. Analysis of two overlapping partial sequences of the cox1 gene, from individual worms, revealed distinct genetic variation (7-9%) between the Danish worms and isolates of S. lupi from Europe, Asia and Africa. This was confirmed by phylogenetic analysis that clearly separated the Danish worms from other isolates of S. lupi. The distinct genetic differences of the current worms compared to other isolates of S. lupi may suggest the presence of a cryptic species within Spirocerca. Copyright © 2014 Elsevier B.V. All rights reserved.
Lu, Y; Qi, Y X; Zhang, H; Zhang, H Q; Pu, J J; Xie, Y X
2013-12-19
To establish a proteomic reference map of Musa acuminate Colla (banana) leaf, we separated and identified leaf proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS). Tryptic digests of 44 spots were subjected to peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS. Three spots that were not identified by MALDI-TOF MS analysis were identified by searching against the NCBInr, SwissProt, and expressed sequence tag (EST) databases. We identified 41 unique proteins. The majority of the identified leaf proteins were found to be involved in energy metabolism. The results indicate that 2D-PAGE is a sensitive and powerful technique for the separation and identification of Musa leaf proteins. A summary of the identified proteins and their putative functions is discussed.
Zhang, Yao; Huang, Jingfeng; Wang, Fumin; Blackburn, George Alan; Zhang, Hankui K; Wang, Xiuzhen; Wei, Chuanwen; Zhang, Kangyu; Wei, Chen
2017-07-25
The PROSPECT leaf optical model has, to date, well-separated the effects of total chlorophyll and carotenoids on leaf reflectance and transmittance in the 400-800 nm. Considering variations in chlorophyll a:b ratio with leaf age and physiological stress, a further separation of total plant-based chlorophylls into chlorophyll a and chlorophyll b is necessary for advanced monitoring of plant growth. In this study, we present an extended version of PROSPECT model (hereafter referred to as PROSPECT-MP) that can combine the effects of chlorophyll a, chlorophyll b and carotenoids on leaf directional hemispherical reflectance and transmittance (DHR and DHT) in the 400-800 nm. The LOPEX93 dataset was used to evaluate the capabilities of PROSPECT-MP for spectra modelling and pigment retrieval. The results show that PROSPECT-MP can both simultaneously retrieve leaf chlorophyll a and b, and also performs better than PROSPECT-5 in retrieving carotenoids concentrations. As for the simulation of DHR and DHT, the performances of PROSPECT-MP are similar to that of PROSPECT-5. This study demonstrates the potential of PROSPECT-MP for improving capabilities of remote sensing of leaf photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids) and for providing a framework for future refinements in the modelling of leaf optical properties.
NASA Astrophysics Data System (ADS)
Xie, Qinxing; Huang, Xiaolin; Zhang, Yufeng; Wu, Shihua; Zhao, Peng
2018-06-01
The main components of a supercapacitor include two electrodes, electrolyte, and a separator, which are all essential to specify the energy storage capability of the device. In this work, two kinds of porous carbon materials have been fabricated via different routes using pomelo peel as raw material. The specific surface area are 1187 m2 g-1 for the nanosized worm-like carbon, and 1744 m2 g-1 for the nitrogen-enriched microsized carbon. Both carbon materials demonstrate excellent energy storage capability as electrodes for aqueous supercapacitors. According to the three-electrode measurements, the worm-like carbon exhibits a high specific capacitance of 316 F g-1 at 0.2 A g-1 in 6 M KOH, while the other exhibits 471 F g-1 due to the highly enriched nitrogen atoms in structure. In addition, two-electrode coin-type cells have been assembled with the carbon materials as electrodes and hydrophilic poly(vinylidene fluoride) porous membrane as the separator. The assembled cells exhibit high specific capacitances, excellent rate performance and superior cycling durability because of a synergistic effect of the high performance carbon electrodes and hydrophilic porous separator.
Hepatic fascioliasis in Mashhad, Northeast Iran: first report.
Badirzadeh, Alireza; Sabzevari, Sadaf
2017-01-01
Fascioliasis is a zoonotic disease caused by a leaf-like worm (fluke) called Fasciola. Herein, we present a case of human hepatic fascioliasis. A 57-year-old man was referred to the hospital for ambiguous gastrointestinal symptoms with suspected hemangioma. Hepatic fascioliasis was diagnosed using abdominal computed tomography and serology. He tested positive for the IgG antibody against Fasciola hepatica. The patient was treated successfully with triclabendazole. This is the first published report on the occurrence of fascioliasis in Northeast Iran, a non-endemic area for fascioliasis. Our results suggest the emergence of a new focus in the region.
Diffuse and specular characteristics of leaf reflectance
NASA Technical Reports Server (NTRS)
Grant, Lois
1987-01-01
In this paper, the evolution of current understanding of the mechanisms of leaf reflectance is reviewed. The use of measurements of polarized reflectance to separate leaf reflectance into diffuse and specular components is discussed. A section on the factors influencing leaf reflectance - leaf structure and physiological disturbances - is included along with discussion on the manner in which these influences are manifested.
C. elegans positive butanone learning, short-term, and long-term associative memory assays.
Kauffman, Amanda; Parsons, Lance; Stein, Geneva; Wills, Airon; Kaletsky, Rachel; Murphy, Coleen
2011-03-11
The memory of experiences and learned information is critical for organisms to make choices that aid their survival. C. elegans navigates its environment through neuron-specific detection of food and chemical odors, and can associate nutritive states with chemical odors, temperature, and the pathogenicity of a food source. Here, we describe assays of C. elegans associative learning and short- and long-term associative memory. We modified an aversive olfactory learning paradigm to instead produce a positive response; the assay involves starving ~400 worms, then feeding the worms in the presence of the AWC neuron-sensed volatile chemoattractant butanone at a concentration that elicits a low chemotactic index (similar to Toroyama et al.). A standard population chemotaxis assay1 tests the worms' attraction to the odorant immediately or minutes to hours after conditioning. After conditioning, wild-type animals' chemotaxis to butanone increases ~0.6 Chemotaxis Index units, its "Learning Index". Associative learning is dependent on the presence of both food and butanone during training. Pairing food and butanone for a single conditioning period ("massed training") produces short-term associative memory that lasts ~2 hours. Multiple conditioning periods with rest periods between ("spaced training") yields long-term associative memory (<40 hours), and is dependent on the cAMP Response Element Binding protein (CREB), a transcription factor required for long-term memory across species. Our protocol also includes image analysis methods for quick and accurate determination of chemotaxis indices. High-contrast images of animals on chemotaxis assay plates are captured and analyzed by worm counting software in MatLab. The software corrects for uneven background using a morphological tophat transformation. Otsu's method is then used to determine a threshold to separate worms from the background. Very small particles are removed automatically and larger non-worm regions (plate edges or agar punches) are removed by manual selection. The software then estimates the size of single worm by ignoring regions that are above a specified maximum size and taking the median size of the remaining regions. The number of worms is then estimated by dividing the total area identified as occupied by worms by the estimated size of a single worm. We have found that learning and short- and long-term memory can be distinguished, and that these processes share similar key molecules with higher organisms. Our assays can quickly test novel candidate genes or molecules that affect learning and short- or long-term memory in C. elegans that are relevant across species.
Kiazolu, J Boima; Intisar, Azeem; Zhang, Lingyi; Wang, Yun; Zhang, Runsheng; Wu, Zhongping; Zhang, Weibing
2016-10-01
Morinda morindoides is an important Liberian traditional medicine for the treatment of malaria, fever, worms etc. The plant was subjected to integrated approaches including phytochemical screening and gas chromatography mass spectrometry (GC-MS) analyses. Phytochemical investigation of the powdered plant revealed the presence of phenolics, tannins, flavonoids, saponins, terpenes, steroidal compounds and volatile oil. Steam distillation followed by GC-MS resulted in the identification of 47 volatiles in its aerial parts: 28 were in common including various bioactive volatiles. Major constituents of leaves were phytol (43.63%), palmitic acid (8.55%) and geranyl linalool (6.95%) and stem were palmitic acid (14.95%), eicosane (9.67%) and phytol (9.31%), and hence, a significant difference in the percentage composition of aerial parts was observed. To study seasonal changes, similarity analysis was carried out by calculating correlation coefficient (r) and vector angle cosine (z) that were more than 0.91 for stem-to-stem and leaf-to-leaf batches indicating considerable consistency.
Leah S. Bauer; Joann Meerschaert; Thomas O. Forrester
1989-01-01
An artificial diet was developed for labortory rearing of the cottonwood leaf beetle, Chrysomela scripta F., and the imported willow leaf beetle, Plagiodera versicolira (Laicharting). To reduce microbial contamination of the media, procedures were developed for the separating egg masses and sterilizing egg surfaces. Cottonwood leaf...
NASA Astrophysics Data System (ADS)
Feng, Chenchen; Jiao, Zhengbo; Li, Shaopeng; Zhang, Yan; Bi, Yingpu
2015-12-01
We demonstrate a facile method for the rational fabrication of pore-size controlled nanoporous BiVO4 photoanodes, and confirmed that the optimum pore-size distributions could effectively absorb visible light through light diffraction and confinement functions. Furthermore, in situ X-ray photoelectron spectroscopy (XPS) reveals more efficient photoexcited electron-hole separation than conventional particle films, induced by light confinement and rapid charge transfer in the inter-crossed worm-like structures.We demonstrate a facile method for the rational fabrication of pore-size controlled nanoporous BiVO4 photoanodes, and confirmed that the optimum pore-size distributions could effectively absorb visible light through light diffraction and confinement functions. Furthermore, in situ X-ray photoelectron spectroscopy (XPS) reveals more efficient photoexcited electron-hole separation than conventional particle films, induced by light confinement and rapid charge transfer in the inter-crossed worm-like structures. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06584d
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fitzgerald, D.; Lanno, R.P.; Farwell, A.
Although methods for standardized toxicity tests with earthworms exist, many of the test parameters and conditions have not been validated in actual tests and with different species of worms. This study evaluated the toxicity of pentachlorophenol (PCP) to three species of earthworms, Lumbricus terrestris, Eisenia fetida, and Eudrilus eugeniae using various methods of data analysis and body residues. Tests were conducted in artificial soil for a period of 28 days or until an Acute Lethality Threshold (ALT) was reached. An intensive temporal sampling regime was applied to generate sufficient data for the accurate estimation of ALTs using both LC50/time andmore » time-to-death/soil concentration methods of data analysis. L. terrestris was tested at 15 C, E. eugeniae at 24 C, and E. fetida at both temperatures. Total body residues of PCP were measured by GC following cryogenic separation of the lipid fraction of the worm. ALTs were significantly different between E. fetida and the two larger species of worms. No effect of temperature on the ALT for E. fetida was observed, although the time taken to reach the ALT increased at the lower temperature. The relationship of PCP residues at mortality will be discussed in terms of the effects of species, body size and temperature. Limitations of the artificial soil based upon growth curves of worms will also be examined.« less
Exploring the World Beneath Your Feet.
ERIC Educational Resources Information Center
Flass, Christine A.
1984-01-01
A clod of soil contains a multitude of different organisms that can be used to teach students about the invaluable services of soil-dwellers. Activities presented are identifying vertebrate and invertebrate soil-dwellers, learning functions of earthworms, conducting a soil 'population survey', starting a worm culture, and separating anthropods…
Mesbah, H A; Mourad, A K; Rokaia, A Z M
2006-01-01
The present work was conducted to evaluate the efficiency of two essential oils ((Flax or "Linseed" and Sesame ), five volatile plant oils ( Camphor, Red basil, Rose, Menthol and Clove ), four pesticides (Methoxyfenozide; Permethrin; Profenofos and Spinosad) and their mixtures on the cotton leaf-worm Spodoptera littoralis (Boisd.). This study was also devoted to minimize the usage of conventional insecticides, reduce the environmental pollution, and protect human-beings and domestic animals from hazards due to pesticides applications. In the meantime, the delayed effect of these tested plant oils on the developing immatures and moths of the cotton leaf-worm, Spodoptera littoralis was determined. Most of the evaluated plant oils were found to have an insecticidal effect on the 4th instar larvae of the cotton leaf-worm, S. littoralis. Both the essential Sesame oil and Clove volatile oil showed rather weak toxic effect corresponding to the same concentrations and periods of the bioassay tests. Comparing the toxicity of the tested plant oils, it was affirmed that both Rose and Red basil volatile oils were the highest efficient natural phytocompounds against the treated larvae and alternatively ranked either the 1st and/or the 2nd rank, throughout the different periods of the bioassay tests, followed by the other three tested oils which were more or less efficient phytocompounds. According to the toxicity index, all the tested oils were less toxic than the superior Red basil volatile oil after 48 h. post treatment followed by the gradual decrease in toxicity of Rose, Flax and Menthol, respectively. The development of the treated 4th larval instar was blocked due to treatment with the tested plant oils. With no exception, all the efficiently tested essential and/or volatile oils acted principally as Insect Growth Inhibitors (IGIs) rather than antifeedants causing disruption of the insect development, abnormal larvae, pupae and adults that were lead finally to death. The tested mixtures of Clove and Sesame oils increased the percentage of larval mortality in comparison to their use alone against the treated 4th larval instar.Contrarily, antagonism was revealed for the mixture of Sesame/Flax oils, the calculated value of LC50 greatly increased compared to the corresponding values of their individual evaluation after 48 h. from initiating the treatment. The delayed effect of tested plant oils was inspected on certain parameters of the fitness components of the subject insect and was mainly determined for the rates of hatched eggs and emerged moths. Remarkably, the Methoxyfenozide treated 4th larval instar became passive, or ceased feeding on the treated leaves and were unable to complete normally the moulting process, which partially took place in most'of the other treated individuals. The treated larvae with the tested lower concentrations, hardly succeeded in completing moulting process. The survived larvae failed to complete the next moulting at the end of the treatments. The toxic effect of Spinosad was more apparent against the treated larvae after 72 h from application. The calculated LC50 values indicated the gradual increase of its toxic effect in the subsequent prolonged intervals of the test. Spinosad showed its activity either by contact or ingestion and caused larval characteristic symptoms. Permethrin exhibited superior toxic efficacy overall the other tested chemicals, during the period from 72 up to 96 h post treatment. The gradual increase of the toxic effect of Permethrin indicated an efficient continuous persistence of nervous toxicity. According to the specific properties of Profenofos, results revealed that the toxicity by ingestion was more potential than by contact and explained the reason of developing toxicity with the increase of bioassay inspection period. The comparative toxic efficiency of the tested insecticides proved that Permethrin was the most effective one, giving LC50 values of 2.92 and 1.53 ppm after 72 and 96 h. bioassay, respectively, followed by Profenofos, Methoxyfenozide and Spinosad, successively. In addition, the calculated values of toxicity index also proved that all the tested compounds were less toxic than Permethrin (as a standard compound ). It is worth mentioning that the combined action of the mixed pesticides with four efficient volatile plant oils showed synergistic action against the 4th larval instar of S. littoralis.
Dissecting a new connection between cytokinin and jasmonic acid in control of leaf growth
USDA-ARS?s Scientific Manuscript database
Plant growth is mediated by two cellular processes: division and elongation. The maize leaf is an excellent model to study plant growth since these processes are spatially separated into discreet zones - a division zone (DZ), transition zone (TZ), and elongation zone (EZ) - at the base of the leaf. ...
Lin, Miao; Chu, Qing-Cui; Tian, Xiu-Hui; Ye, Jian-Nong
2007-01-01
Corn has been known for its accumulation of flavones and phenolic acids. However, many parts of corn, except kernel, have not drawn much attention. In this work, a method based on capillary zone electrophoresis with electrochemical detection has been used for the separation and determination of epicatechin, rutin, ascorbic acid (Vc), kaempferol, chlorogenic acid, and quercetin in corn silk, leaf, and kernel. The distribution comparison of the ingredients among silk, leaf, and kernel is discussed. Several important factors--including running buffer acidity, separation voltage, and working electrode potential--were evaluated to acquire the optimum analysis conditions. Under the optimum conditions, the analytes could be well separated within 19 min in a 40-mmol/L borate buffer (pH 9.2). The response was linear over three orders of magnitude with detection limits (S/N = 3) ranging from 4.97 x 10(-8) to 9.75 x 10(-8) g/mL. The method has been successfully applied for the analysis of corn silk, leaf, and kernel with satisfactory results.
Ishida, Atsushi; Nakano, Takashi; Yazaki, Kenichi; Matsuki, Sawako; Koike, Nobuya; Lauenstein, Diego L; Shimizu, Michiru; Yamashita, Naoko
2008-05-01
We examined 15 traits in leaves and stems related to leaf C economy and water use for 32 co-existing angiosperms at ridge sites with shallow soil in the Bonin Islands. Across species, stem density was positively correlated to leaf mass per area (LMA), leaf lifespan (LLS), and total phenolics and condensed tannins per unit leaf N (N-based), and negatively correlated to leaf osmotic potential and saturated water content in leaves. LMA and LLS were negatively correlated to photosynthetic parameters, such as area-, mass-, and N-based assimilation rates. Although stem density and leaf osmotic potential were not associated with photosynthetic parameters, they were associated with some parameters of the leaf C economy, such as LMA and LLS. In the principal component (PCA) analysis, the first three axes accounted for 74.4% of total variation. Axis 1, which explained 41.8% of the total variation, was well associated with parameters for leaf C and N economy. Similarly, axis 2, which explained 22.3% of the total variation, was associated with parameters for water use. Axis 3, which explained 10.3% of the total variation, was associated with chemical defense within leaves. Axes 1 and 2 separated functional types relatively well, i.e., creeping trees, ruderal trees, other woody plants, C(3) shrubs and forbs, palms, and CAM plants, indicating that plant functional types were characterized by similar attributes of traits related to leaf C and N economy and water use. In addition, when the plot was extended by two unrelated traits, leaf mass-based assimilation rates and stem density, it also separated these functional types. These data indicate that differences in the functional types with contrasting plant strategies can be attributed to functional integration among leaf C economy, hydraulics, and leaf longevity, and that both leaf mass-based assimilation rates and stem density are key factors reflecting the different functions of plant species.
van Wyk, J A; Meyer, J; van Rensburg, L J
2003-03-01
As part of a trial to test the profitability of finishing weaner lambs over winter and spring on the Highveld of Gauteng province, an investigation was carried out over 4 consecutive years as to whether or not worm control was necessary while the lambs were on irrigated, improved pastures. Pastures that had not been grazed by sheep or other livestock for at least 5 years were planted to annual ryegrass (Lolium multiflora) that was ploughed under and replanted annually. Weaner lambs were randomly divided into either 2 (A and B) or 3 (A, B and C) groups and finished from April/May to November/December on a separate pasture per group. While Group A lambs were dewormed before being placed on pasture, those in Groups B and C were not. Faecal egg counts were performed at irregular intervals, and when the lambs were sold at the conclusion of each year's trial, the gastrointestinal tracts of 4-5 lambs per trial group were processed for worm recovery. Haemonchus contortus was the dominant worm species, while Trichostrongylus colubriformis, Ostertagia circumcincta and Trichuris spp. were encountered sporadically. From the results obtained it seems unlikely that there is appreciable 'carry-over' of the various worm species from year to year on pastures that are ploughed and replanted annually; thus it is improbable that there will be a build-up of anthelmintic-resistant worms. While on pasture, no drenching was required for the Group A lambs (dewormed before placing on the pasture), nor in 2 of the 4 years in Groups B or B+C that were not drenched and were lightly infected at the start. In the remaining 2 years Groups B or B+C were drenched once only during the course of each trial. Thus, under the conditions as in this study, little worm control is necessary, provided faecal worm egg counts are done to gauge the levels of infection before the lambs are placed on pasture, and to guard against the possibility of an increase in worm burdens thereafter in some years. Also, because of the apparent lack of carry-over between years, anthelmintic treatment at the time of introduction of the lambs or during the period of finishing should be safe as regards progressive selection for anthelmintic resistance. It is also likely to be cost-effective, considering the low cost of anthelmintics in relation to the price of lambs, to counter the possibility of a loss in production if lambs were to harbour relatively heavy worm burdens when introduced.
Gayen, Srimonta; Mandal, Chandi Charan; Samanta, Milan Kumar; Dey, Avishek; Sen, Soumitra Kumar
2016-04-01
Emergence of resistant insects limits the sustainability of Bacillus thuringiensis (Bt) transgenic crop plants for insect management. Beside this, the presence of unwanted marker gene(s) in the transgenic crops is also a major environmental and health concern. Thus, development of marker free transgenic crop plants expressing a new class of toxin having a different mortality mechanism is necessary for resistance management. In a previous study, we generated an engineered Cry2Aa (D42/K63F/K64P) toxin which has a different mortality mechanism as compared to first generation Bt toxin Cry1A, and this engineered toxin was found to enhance 4.1-6.6-fold toxicity against major lepidopteran insect pests of crop plants. In the present study, we have tested the potency of this engineered synthetic Cry2Aa (D42/K63F/K64P) toxin as a candidate in the development of insect resistant transgenic tobacco plants. Simultaneously, we have eliminated the selectable marker gene from the Cry2Aa (D42/K63F/K64P) expressing tobacco plants by exploiting the Cre/lox mediated recombination methodology, and successfully developed marker free T2 transgenic tobacco plants expressing the engineered Cry2Aa toxin. Realtime and western blot analysis demonstrated the expression of engineered toxin gene in transgenic plants. Insect feeding assays revealed that the marker free T2 progeny of transgenic plants expressing Cry2Aa (D42/K63F/K64P) toxin showed 82-92 and 52-61 % mortality to cotton leaf worm (CLW) and cotton bollworm (CBW) respectively. Thus, this engineered Cry2Aa toxin could be useful for the generation of insect resistant transgenic Bt lines which will protect the crop damages caused by different insect pests such as CLW and CBW.
NASA Astrophysics Data System (ADS)
Shih, Po-Chen; Su, Yi-Jr; Chen, Ke-Min; Jen, Lin-Ni; Liu, Cheng-tzu; Hsu, Long
2005-08-01
Granulocytes are a group of white blood cells belonging to the innate immune system in human and in murine in which eosinophils play an important role in worm infection-induced inflammation. The migration of these cells is well characterized and has been separated into four steps: rolling, adhesion, transendothelial migration, and chemotaxis, however, the physical characteristics of the chemotactic force to eosinophils from worm component remain largely unknown. Note that optical tweezers are featured in the manipulation of a single cell and the measurement of biological forces. Therefore, we propose to use optical tweezers to examine the chemotactic force to a eosinophil from a T. canis lavae preparation in terms of distance during the migration of eosinophil.
Single-hole spectral function and spin-charge separation in the t-J model
NASA Astrophysics Data System (ADS)
Mishchenko, A. S.; Prokof'ev, N. V.; Svistunov, B. V.
2001-07-01
Worm algorithm Monte Carlo simulations of the hole Green function with subsequent spectral analysis were performed for 0.1<=J/t<=0.4 on lattices with up to L×L=32×32 sites at a temperature as low as T=J/40, and present, apparently, the hole spectral function in the thermodynamic limit. Spectral analysis reveals a δ-function-sharp quasiparticle peak at the lower edge of the spectrum that is incompatible with the power-law singularity and thus rules out the possibility of spin-charge separation in this parameter range. Spectral continuum features two peaks separated by a gap ~4÷5 t.
A microfluidic array for high-content screening at whole-organism resolution
NASA Astrophysics Data System (ADS)
Migliozzi, D.; Cornaglia, M.; Mouchiroud, L.; Auwerx, J.; Gijs, M. A. M.
2018-02-01
A main step for the development and the validation of medical drugs is the screening on whole organisms, which gives the systemic information that is missing when using cellular models. Among the organisms of choice, Caenorhabditis elegansis a soil worm which catches the interest of researchers who study systemic physiopathology (e.g. metabolic and neurodegenerative diseases) because: (1) its large genetic homology with humans supports translational analysis; (2) worms are much easier to handle and grow in large amounts compared to rodents, for which (3) the costs and (4) the ethical concerns are substantial.C. elegansis therefore well suited for large screens, dose-response analysis and target-discovery involving an entire organism. We have developed and tested a microfluidic array for high-content screening, enabling the selection of small populations of its first larval stage in many separated chambers divided into channels for multiplexed screens. With automated protocols for feeding, drug administration and image acquisition, our chip enables the study of the nematodes throughout their entire lifespan. By using a paralyzing agent and a mitochondrial-stress inducer as case studies, we have demonstrated large field-of-view motility analysis, and worm-segmentation/signal-detection for mode-of-action quantification with genetically-encoded fluorescence reporters.
Ren, Jing; Bai, Ming; Yang, Xing-Ke; Zhang, Run-Zhi; Ge, Si-Qin
2017-01-01
The success of beetles is mainly attributed to the possibility to hide the hindwings under the sclerotised elytra. The acquisition of the transverse folding function of the hind wing is an important event in the evolutionary history of beetles. In this study, the morphological and functional variances in the hind wings of 94 leaf beetle species (Coleoptera: Chrysomelinae) is explored using geometric morphometrics based on 36 landmarks. Principal component analysis and Canonical variate analysis indicate that changes of apical area, anal area, and middle area are three useful phylogenetic features at a subtribe level of leaf beetles. Variances of the apical area are the most obvious, which strongly influence the entire venation variance. Partial least squares analysis indicates that the proximal and distal parts of hind wings are weakly associated. Modularity tests confirm that the proximal and distal compartments of hind wings are separate modules. It is deduced that for leaf beetles, or even other beetles, the hind wing possibly exhibits significant functional divergences that occurred during the evolution of transverse folding that resulted in the proximal and distal compartments of hind wings evolving into separate functional modules.
Ding, Risheng; Kang, Shaozhong; Du, Taisheng; Hao, Xinmei; Zhang, Yanqun
2014-01-01
The dual-source Shuttleworth-Wallace model has been widely used to estimate and partition crop evapotranspiration (λET). Canopy stomatal conductance (Gsc), an essential parameter of the model, is often calculated by scaling up leaf stomatal conductance, considering the canopy as one single leaf in a so-called "big-leaf" model. However, Gsc can be overestimated or underestimated depending on leaf area index level in the big-leaf model, due to a non-linear stomatal response to light. A dual-leaf model, scaling up Gsc from leaf to canopy, was developed in this study. The non-linear stomata-light relationship was incorporated by dividing the canopy into sunlit and shaded fractions and calculating each fraction separately according to absorbed irradiances. The model includes: (1) the absorbed irradiance, determined by separately integrating the sunlit and shaded leaves with consideration of both beam and diffuse radiation; (2) leaf area for the sunlit and shaded fractions; and (3) a leaf conductance model that accounts for the response of stomata to PAR, vapor pressure deficit and available soil water. In contrast to the significant errors of Gsc in the big-leaf model, the predicted Gsc using the dual-leaf model had a high degree of data-model agreement; the slope of the linear regression between daytime predictions and measurements was 1.01 (R2 = 0.98), with RMSE of 0.6120 mm s-1 for four clear-sky days in different growth stages. The estimates of half-hourly λET using the dual-source dual-leaf model (DSDL) agreed well with measurements and the error was within 5% during two growing seasons of maize with differing hydrometeorological and management strategies. Moreover, the estimates of soil evaporation using the DSDL model closely matched actual measurements. Our results indicate that the DSDL model can produce more accurate estimation of Gsc and λET, compared to the big-leaf model, and thus is an effective alternative approach for estimating and partitioning λET.
Adaptation of gastrointestinal nematode parasites to host genotype: single locus simulation models
2013-01-01
Background Breeding livestock for improved resistance to disease is an increasingly important selection goal. However, the risk of pathogens adapting to livestock bred for improved disease resistance is difficult to quantify. Here, we explore the possibility of gastrointestinal worms adapting to sheep bred for low faecal worm egg count using computer simulation. Our model assumes sheep and worm genotypes interact at a single locus, such that the effect of an A allele in sheep is dependent on worm genotype, and the B allele in worms is favourable for parasitizing the A allele sheep but may increase mortality on pasture. We describe the requirements for adaptation and test if worm adaptation (1) is slowed by non-genetic features of worm infections and (2) can occur with little observable change in faecal worm egg count. Results Adaptation in worms was found to be primarily influenced by overall worm fitness, viz. the balance between the advantage of the B allele during the parasitic stage in sheep and its disadvantage on pasture. Genetic variation at the interacting locus in worms could be from de novo or segregating mutations, but de novo mutations are rare and segregating mutations are likely constrained to have (near) neutral effects on worm fitness. Most other aspects of the worm infection we modelled did not affect the outcomes. However, the host-controlled mechanism to reduce faecal worm egg count by lowering worm fecundity reduced the selection pressure on worms to adapt compared to other mechanisms, such as increasing worm mortality. Temporal changes in worm egg count were unreliable for detecting adaptation, despite the steady environment assumed in the simulations. Conclusions Adaptation of worms to sheep selected for low faecal worm egg count requires an allele segregating in worms that is favourable in animals with improved resistance but less favourable in other animals. Obtaining alleles with this specific property seems unlikely. With support from experimental data, we conclude that selection for low faecal worm egg count should be stable over a short time frame (e.g. 20 years). We are further exploring model outcomes with multiple loci and comparing outcomes to other control strategies. PMID:23714384
Temporal versus spatial variation in leaf reflectance under changing water stress conditions
NASA Technical Reports Server (NTRS)
Cohen, Warren B.
1991-01-01
Leaf reflectance changes associated with changes in water stress were analyzed in two separate experiments. Results indicate that the variation in reflectance among collections of leaves of a given species all at the same level of water stress is at least as great as the variation in reflectance associated with changes in water stress for a given leaf collection of that species. The implications is that results from leaf reflectance-water stress studies have only limited applicability to the remote sensing of plant canopy water stress.
Ding, Risheng; Kang, Shaozhong; Du, Taisheng; Hao, Xinmei; Zhang, Yanqun
2014-01-01
The dual-source Shuttleworth-Wallace model has been widely used to estimate and partition crop evapotranspiration (λET). Canopy stomatal conductance (Gsc), an essential parameter of the model, is often calculated by scaling up leaf stomatal conductance, considering the canopy as one single leaf in a so-called “big-leaf” model. However, Gsc can be overestimated or underestimated depending on leaf area index level in the big-leaf model, due to a non-linear stomatal response to light. A dual-leaf model, scaling up Gsc from leaf to canopy, was developed in this study. The non-linear stomata-light relationship was incorporated by dividing the canopy into sunlit and shaded fractions and calculating each fraction separately according to absorbed irradiances. The model includes: (1) the absorbed irradiance, determined by separately integrating the sunlit and shaded leaves with consideration of both beam and diffuse radiation; (2) leaf area for the sunlit and shaded fractions; and (3) a leaf conductance model that accounts for the response of stomata to PAR, vapor pressure deficit and available soil water. In contrast to the significant errors of Gsc in the big-leaf model, the predicted Gsc using the dual-leaf model had a high degree of data-model agreement; the slope of the linear regression between daytime predictions and measurements was 1.01 (R2 = 0.98), with RMSE of 0.6120 mm s−1 for four clear-sky days in different growth stages. The estimates of half-hourly λET using the dual-source dual-leaf model (DSDL) agreed well with measurements and the error was within 5% during two growing seasons of maize with differing hydrometeorological and management strategies. Moreover, the estimates of soil evaporation using the DSDL model closely matched actual measurements. Our results indicate that the DSDL model can produce more accurate estimation of Gsc and λET, compared to the big-leaf model, and thus is an effective alternative approach for estimating and partitioning λET. PMID:24752329
The effect of glyphosate on import into a sink leaf of sugar beet
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shieh, Wenjang; Geiger, D.R.
1990-05-01
The basis for glyphosate inducted limitation of carbon import into developing leaves was studied in sugar beet. To separate the effects of the herbicide on export from those on import, glyphosate was supplied to a developing leaf from two exporting source leaves which fed the sink leaf. Carbon import into the sink leaf was determined by supplying {sup 14}CO{sub 2} to a third source leaf which also supplies carbon to the monitored sink leaf. Import into the sink leaf decreased within 2 to 3 h after glyphosate application, even though photosynthesis and export in the source leaf supplying {sup 14}Cmore » were unaffected. Reduced import into the sink leaf was accompanied by increased import by the tap root. Elongation of the sink leaf was only slightly decreased following arrival of glyphosate. Photosynthesis by the sink leaf was not inhibited. The results to data support the view that import is slowed by the inhibition of synthesis of structural or storage compounds in the developing leaves.« less
Ishida, Naoyuki
2011-08-26
An improved separation method for chlorophyll metabolites in Oriental tobacco leaf was developed. While Oriental leaf still gives the green color even after the curing process, little attention has been paid to the detailed composition of the remaining green pigments. This study aimed to identify the green pigments using non aqueous reversed phase chromatography (NARPC). To this end, liquid chromatograph (LC) equipped with a photo diode array detector (DAD) and an atmospheric pressure chemical ionization/mass spectrometer (APCI/MSD) was selected, because it is useful for detecting low polar non-volatile compounds giving green color such as pheophytin a. Identification was based on the wavelength spectrum, mass spectrum and retention time, comparing the analytes in Oriental leaf with the commercially available and synthesized components. Consequently, several chlorophyll metabolites such as hydroxypheophytin a, solanesyl pheophorbide a and solanesyl hydroxypheophorbide a were newly identified, in addition to typical green pigments such as chlorophyll a and pheophytin a. Chlorophyll metabolites bound to solanesol were considered the tobacco specific components. NARPC expanded the number of detectable low polar chlorophyll metabolites in Oriental tobacco leaf. Copyright © 2011 Elsevier B.V. All rights reserved.
QuantWorm: a comprehensive software package for Caenorhabditis elegans phenotypic assays.
Jung, Sang-Kyu; Aleman-Meza, Boanerges; Riepe, Celeste; Zhong, Weiwei
2014-01-01
Phenotypic assays are crucial in genetics; however, traditional methods that rely on human observation are unsuitable for quantitative, large-scale experiments. Furthermore, there is an increasing need for comprehensive analyses of multiple phenotypes to provide multidimensional information. Here we developed an automated, high-throughput computer imaging system for quantifying multiple Caenorhabditis elegans phenotypes. Our imaging system is composed of a microscope equipped with a digital camera and a motorized stage connected to a computer running the QuantWorm software package. Currently, the software package contains one data acquisition module and four image analysis programs: WormLifespan, WormLocomotion, WormLength, and WormEgg. The data acquisition module collects images and videos. The WormLifespan software counts the number of moving worms by using two time-lapse images; the WormLocomotion software computes the velocity of moving worms; the WormLength software measures worm body size; and the WormEgg software counts the number of eggs. To evaluate the performance of our software, we compared the results of our software with manual measurements. We then demonstrated the application of the QuantWorm software in a drug assay and a genetic assay. Overall, the QuantWorm software provided accurate measurements at a high speed. Software source code, executable programs, and sample images are available at www.quantworm.org. Our software package has several advantages over current imaging systems for C. elegans. It is an all-in-one package for quantifying multiple phenotypes. The QuantWorm software is written in Java and its source code is freely available, so it does not require use of commercial software or libraries. It can be run on multiple platforms and easily customized to cope with new methods and requirements.
Neem leaves as a source of fertilizer-cum-pesticide vermicompost.
Gajalakshmi, S; Abbasi, S A
2004-05-01
Vermicomposting of neem (Azadirachta indica A. Juss) was accomplished in "high-rate" reactors operated at the earthworm (Eudrilus eugeniae) densities of 62.5 and 75 animals per litre of reactor volume. Contrary to the fears that neem--a powerful nematicide--might not be palatable to the annelids, the earthworms fed voraciously on the neem compost, converting upto 7% of the feed into vermicompost per day. Indeed the worms grew faster and reproduced more rapidly in the neem-fed vermireactors than in the reactors fed with mango leaf litter earlier studied by the authors (Gajalakshmi et al., 2003). Another set of experiments on the growth, flowering, and fruition of brinjal (Solanum melongena) plants with and without fertilization with vermicompost, revealed that the vermicompost had a significantly beneficial impact.
Badary, Dalia M.; Sayed, Hesham M. B.; Bayoumi, Soad A. H.; Khalifa, Azza A.; El-Moghazy, Ahmed M.
2016-01-01
Due to the development of praziquantel (PZQ) schistosomes resistant strains, the discovery of new antischistosomal agents is of high priority in research. This work reported the in vitro and in vivo effects of the edible and ornamental pomegranate extracts against Schistosoma mansoni. Leaves and stem bark ethanolic extracts of both dried pomegranates were prepared at 100, 300, and 500 μg/mL for in vitro and 600 and 800 mg/kg for in vivo. Adult worms Schistosoma mansoni in RPMI-1640 medium for in vitro and S. mansoni infected mice for in vivo tests were obtained from Theodor Bilharz Research Institute, Cairo, Egypt. In vitro activity was manifested by significant coupled worms separation, reduction of motor activity, lethality, and ultrastructural tegumental alterations in adult worms. In vivo activity was manifested revealed by significant reduction of hepatic granulomas number and diameter, decreased number of bilharzial eggs in liver tissues, lowered liver inflammatory infiltration, decreased hepatic fibrosis, and inducible nitric oxide synthase (iNOS) expression. Ethanolic stem bark extract of edible pomegranate exhibited highest antischistosomal activities both in vitro and in vivo. Therefore, pomegranate showed a good potential to be used as a promising new candidate for the development of new schistosomicidal agents. PMID:27990425
Murakami, Takumi; Segawa, Takahiro; Dial, Roman; Takeuchi, Nozomu; Kohshima, Shiro; Hongoh, Yuichi
2017-01-01
The community structure of bacteria associated with the glacier ice worm Mesenchytraeus solifugus was analyzed by amplicon sequencing of 16S rRNA genes and their transcripts. Ice worms were collected from two distinct glaciers in Alaska, Harding Icefield and Byron Glacier, and glacier surfaces were also sampled for comparison. Marked differences were observed in bacterial community structures between the ice worm and glacier surface samples. Several bacterial phylotypes were detected almost exclusively in the ice worms, and these bacteria were phylogenetically affiliated with either animal-associated lineages or, interestingly, clades mostly consisting of glacier-indigenous species. The former included bacteria that belong to Mollicutes, Chlamydiae, Rickettsiales, and Lachnospiraceae, while the latter included Arcicella and Herminiimonas phylotypes. Among these bacteria enriched in ice worm samples, Mollicutes, Arcicella, and Herminiimonas phylotypes were abundantly and consistently detected in the ice worm samples; these phylotypes constituted the core microbiota associated with the ice worm. A fluorescence in situ hybridization analysis showed that Arcicella cells specifically colonized the epidermis of the ice worms. Other bacterial phylotypes detected in the ice worm samples were also abundantly recovered from the respective habitat glaciers; these bacteria may be food for ice worms to digest or temporary residents. Nevertheless, some were overrepresented in the ice worm RNA samples; they may also function as facultative gut bacteria. Our results indicate that the community structure of bacteria associated with ice worms is distinct from that in the associated glacier and includes worm-specific and facultative, glacier-indigenous lineages. PMID:28302989
Murakami, Takumi; Segawa, Takahiro; Dial, Roman; Takeuchi, Nozomu; Kohshima, Shiro; Hongoh, Yuichi
2017-03-31
The community structure of bacteria associated with the glacier ice worm Mesenchytraeus solifugus was analyzed by amplicon sequencing of 16S rRNA genes and their transcripts. Ice worms were collected from two distinct glaciers in Alaska, Harding Icefield and Byron Glacier, and glacier surfaces were also sampled for comparison. Marked differences were observed in bacterial community structures between the ice worm and glacier surface samples. Several bacterial phylotypes were detected almost exclusively in the ice worms, and these bacteria were phylogenetically affiliated with either animal-associated lineages or, interestingly, clades mostly consisting of glacier-indigenous species. The former included bacteria that belong to Mollicutes, Chlamydiae, Rickettsiales, and Lachnospiraceae, while the latter included Arcicella and Herminiimonas phylotypes. Among these bacteria enriched in ice worm samples, Mollicutes, Arcicella, and Herminiimonas phylotypes were abundantly and consistently detected in the ice worm samples; these phylotypes constituted the core microbiota associated with the ice worm. A fluorescence in situ hybridization analysis showed that Arcicella cells specifically colonized the epidermis of the ice worms. Other bacterial phylotypes detected in the ice worm samples were also abundantly recovered from the respective habitat glaciers; these bacteria may be food for ice worms to digest or temporary residents. Nevertheless, some were overrepresented in the ice worm RNA samples; they may also function as facultative gut bacteria. Our results indicate that the community structure of bacteria associated with ice worms is distinct from that in the associated glacier and includes worm-specific and facultative, glacier-indigenous lineages.
The confounding effect of understory vegetation contributions to satellite-derived estimates of leaf area index (LAI) was investigated on two loblolly pine (Pinus taeda) forest stands located in Virginia and North Carolina. In order to separate NDVI contributions of the dominantc...
Dharmalingam, Komalavali; Tan, Boon-Khai; Mahmud, Muhd Zulkarnain; Sedek, Saiedatul Akmal Mohamed; Majid, Mohamed Isa Abdul; Kuah, Meng-Kiat; Sulaiman, Shaida Fariza; Ooi, Kheng Leong; Khan, Nurzalina Abdul Karim; Muhammad, Tengku Sifzizul Tengku; Tan, Man-Wah; Shu-Chien, Alexander Chong
2012-01-31
Swietenia macrophylla or commonly known as big leaf mahogany, has been traditionally used as an antibacterial and antifungal agent. The unwanted problem of antibiotic resistance in many bacterial species advocates the need for the discovery of the new anti-infective drugs. Here, we investigated the anti-infective properties of Swietenia macrophylla with an assay involving lethal infection of Caenorhabditis elegans with the opportunistic human pathogen Pseudomonas aeruginosa. Using a slow killing assay, Caenorhabditis elegans was challenged with an infective strain of Pseudomonas aeruginosa (PA14). The ability of Swietenia macrophylla seed ethyl acetate extract to promote the survival of infected worms was assessed by comparing the percentage of survival between extract treated and non-treated worm populations. The effect of Swietenia macrophylla towards PA14 growth, Caenorhabditis elegans feeding rate and degree of PA14 colonization in the worm gut was also evaluated. Lastly, using a fluorescent transgenic Caenorhabditis elegans strain and real time PCR, the effect of Swietenia macrophylla on the expression of lys-7, an immune response gene was also investigated. Our results demonstrate the ability of Swietenia macrophylla seed ethyl acetate extract in rescuing Caenorhabditis elegans from fatal PA14 infection. Consequently, we showed that the extract promotes the survival without exhibiting any bactericidal effect or perturbation of Caenorhabditis elegans feeding rate. We also showed that Swietenia macrophylla was able to restore the initially repressed lys-7 level in PA14 infected Caenorhabditis elegans. Swietenia macrophylla extract is able to enhance the ability of Caenorhabditis elegans to survive PA14 infection without directly killing the pathogen. We further showed that the extract boosted the expression of a gene pivotal for innate immunity in Caenorhabditis elegans. Collectively, these findings strongly suggest the presence of compounds within Swietenia macrophylla seed that either reduces Pseudomonas aeruginosa virulence and/or enhance host resistance. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Measuring ecosystem functioning of soil mega-aggregates produced by soil/litter mix-feeding animals
NASA Astrophysics Data System (ADS)
Kaneko, N.
2009-04-01
Some soil animals are soil/litter mix-feeders. They are known to produce long-lasting soil structures (e.g. casts and molting chamber), and these structures will modify resource availability and environmental conditions for plants and soil organisms. Good examples are epigeic Megascolecid earthworms (Uchida et al., 2004) and Xystodesmid millipeds (Toyota et al., 2006), both found in Japan. In this study we examined chemical, physical and biological properties of soil focusing on multi-functioning of aggregates made by these animals. Since 2003, we manipulated densities of epigeic earthworms in a field encloser (35 m2) (three replications) at a cool temperate forest in Japan. At a no-worm (NW) treatment, all the worms have been collected every year by hand. At the same place, we prepared a control treatment in an encloser (Closed control; CC) and outside the encloser (Open control; OC). We examined surface soil and plant growth after 5-years field manipulation of oak dominated forest. Growth of two Liliaceae forest floor herbs; Smilacina japonica and Polygonatum odoratum, and oak (Quercus crispula) seedlings and canopy oak trees were recorded. Reduction of aggregates after elimination of earthworms was observed in a field condition. The manipulation site showed decreased soil pH, Ca, Mg, and P concentration and total carbon storage was also reduced. There was a negative significant correlation between casts abundance and soil NH4-N, and a positive significance was observed between casts abundance and growth of S. japonica, and oak seedlings. Radial growth of canopy oak trees was decreased at NW treatment compared to CC and OC. Leaf N contents of oak seedling at NW were significantly lower in NW, but canopy oak trees did not show any difference in leaf-N. Although S. japonica and P. odoratum were both found in a same forest floor, S. japonica is known as nutrient limited plants in spring, whereas P. odoratum is light limited. Oak seedlings are depending early growth on their seed nutrient, and the canopy oak trees seem to be nutrient limited. Thus in this forest, the nutrient condition mediated by earthworm activity was a strong factor influencing plant species-specific growth and this correlation was clear when we used the cast abundance as an independent factor but it was not clear when we used the worm abundance or biomass for explanation variables. In laboratory incubations, fresh casts of earthworm Metaphire hilgendorfi contained higher NH4-N which was mostly nitrified within 4-weeks. The 4-weeks aged casts of the earthworm and millipede Parafontaria laminata emitted significantly more N2O whereas the modified soil had strong CH4 acidification capacity. Therefore the animal effects on greenhouse effect gas should be evaluated for CO2, N2O and CH4 at the same time. We then confirmed that megaaggregates, probably cast origin, tended to contain more carbon than fine soil. Combining our data from various study sites in Japan, the amount of carbon contained in megaaggregates (> 2 mm) in 0-5 cm layer ranged from 200 to 1000 g C per m2. Animal feeding activities maintained substantial amount of surface soil aggregates. Therefore, the activity of soil/litter mix feeders can be linked to the carbon dynamics by evaluating worm's soil engineering effect.
21 CFR 520.905a - Fenbendazole suspension.
Code of Federal Regulations, 2013 CFR
2013-04-01
... worms (adults and 4th-stage larvae)—barberpole worm (Haemonchus contortus and H. placei) and small stomach worm (Trichostongylus axei); intestinal worms (adults and 4th-stage larvae)—hookworm (Bunostonmum... control of stomach worm (4th stage inhibited larvae/type II ostertagiasis), Ostertagia ostertagi, and...
21 CFR 520.905a - Fenbendazole suspension.
Code of Federal Regulations, 2014 CFR
2014-04-01
... worms (adults and 4th-stage larvae)—barberpole worm (Haemonchus contortus and H. placei) and small stomach worm (Trichostongylus axei); intestinal worms (adults and 4th-stage larvae)—hookworm (Bunostonmum... control of stomach worm (4th stage inhibited larvae/type II ostertagiasis), Ostertagia ostertagi, and...
NASA Technical Reports Server (NTRS)
McCabe, Gregory J.; Ault, Toby R.; Cook, Benjamin I.; Betancourt, Julio L.; Schwartz, Mark D.
2012-01-01
Detrended, modelled first leaf dates for 856 sites across North America for the period 1900-2008 are used to examine how the El Nino Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) separately and together might influence the timing of spring. Although spring (mean March through April) ENSO and PDO signals are apparent in first leaf dates, the signals are not statistically significant (at a 95% confidence level (p <0.05)) for most sites. The most significant ENSO/PDO signal in first leaf dates occurs for El Nino and positive PDO conditions. An analysis of the spatial distributions of first leaf dates for separate and combined ENSO/PDO conditions features a northwest-southeast dipole that is significantly (at p <0.05) different than the distributions for neutral conditions. The nature of the teleconnection between Pacific SST's and first leaf dates is evident in comparable composites for detrended sea level pressure (SLP) in the spring months. During positive ENSO/PDO, there is an anomalous flow of warm air from the southwestern US into the northwestern US and an anomalous northeasterly flow of cold air from polar regions into the eastern and southeastern US. These flow patterns are reversed during negative ENSO/PDO. Although the magnitudes of first leaf date departures are not necessarily significantly related to ENSO and PDO, the spatial patterns of departures are significantly related to ENSO and PDO. These significant relations and the long-lived persistence of SSTs provide a potential tool for forecasting the tendencies for first leaf dates to be early or late.
Cutaneous Emergence of Eustrongylides in Two Persons from South Sudan
Eberhard, Mark L.; Ruiz-Tiben, Ernesto
2014-01-01
Two large, living worms were collected as they emerged from the lower limb of each of two persons in South Sudan. The worms were observed by staff of the South Sudan Guinea Worm Eradication Program during surveillance activities in communities at-risk for cases of Guinea worm disease (dracunculiasis). The worms measured 7 and 8 cm in length and were identified as fourth-stage larvae of Eustrongylides. This is the first report of such worms emerging from the skin; all five previous reports of human infection involved surgical removal of worms from the peritoneal cavity. PMID:24379241
Müller, Daniel B.; Schubert, Olga T.; Röst, Hannes; Aebersold, Ruedi; Vorholt, Julia A.
2016-01-01
Plants are colonized by a diverse community of microorganisms, the plant microbiota, exhibiting a defined and conserved taxonomic structure. Niche separation based on spatial segregation and complementary adaptation strategies likely forms the basis for coexistence of the various microorganisms in the plant environment. To gain insights into organism-specific adaptations on a molecular level, we selected two exemplary community members of the core leaf microbiota and profiled their proteomes upon Arabidopsis phyllosphere colonization. The highly quantitative mass spectrometric technique SWATH MS was used and allowed for the analysis of over two thousand proteins spanning more than three orders of magnitude in abundance for each of the model strains. The data suggest that Sphingomonas melonis utilizes amino acids and hydrocarbon compounds during colonization of leaves whereas Methylobacterium extorquens relies on methanol metabolism in addition to oxalate metabolism, aerobic anoxygenic photosynthesis and alkanesulfonate utilization. Comparative genomic analyses indicates that utilization of oxalate and alkanesulfonates is widespread among leaf microbiota members whereas, aerobic anoxygenic photosynthesis is almost exclusively found in Methylobacteria. Despite the apparent niche separation between these two strains we also found a relatively small subset of proteins to be coregulated, indicating common mechanisms, underlying successful leaf colonization. Overall, our results reveal for two ubiquitous phyllosphere commensals species-specific adaptations to the host environment and provide evidence for niche separation within the plant microbiota. PMID:27457762
Impact of potato psyllid (Hemiptera: Triozide) feeding on free amino acid composition in potato
USDA-ARS?s Scientific Manuscript database
Foliage feeding impacts of potato psyllid (Bactericera cockerelli) on the free amino acids (FAAs) composition in potato leaf and tuber were determined under the greenhouse conditions. The free amino acids in plant extracts were separated by HPLC, and in both leaf and tuber samples, at least, 17 FAAs...
Microfluidic platform integrated with worm-counting setup for assessing manganese toxicity
Zhang, Beibei; Li, Yinbao; He, Qidi; Qin, Jun; Yu, Yanyan; Li, Xinchun; Zhang, Lin; Yao, Meicun; Liu, Junshan; Chen, Zuanguang
2014-01-01
We reported a new microfluidic system integrated with worm responders for evaluating the environmental manganese toxicity. The micro device consists of worm loading units, worm observing chambers, and a radial concentration gradient generator (CGG). Eight T-shape worm loading units of the micro device were used to load the exact number of worms into the corresponding eight chambers with the assistance of worm responders and doorsills. The worm responder, as a key component, was employed for performing automated worm-counting assay through electric impedance sensing. This label-free and non-invasive worm-counting technique was applied to the microsystem for the first time. In addition, the disk-shaped CGG can generate a range of stepwise concentrations of the appointed chemical automatically and simultaneously. Due to the scalable architecture of radial CGG, it has the potential to increase the throughput of the assay. Dopaminergic (DAergic) neurotoxicity of manganese on C. elegans was quantitatively assessed via the observation of green fluorescence protein-tagged DAergic neurons of the strain BZ555 on-chip. In addition, oxidative stress triggered by manganese was evaluated by the quantitative fluorescence intensity of the strain CL2166. By scoring the survival ratio and stroke frequency of worms, we characterized the dose- and time-dependent mobility defects of the manganese-exposed worms. Furthermore, we applied the microsystem to investigate the effect of natural antioxidants to protect manganese-induced toxicity. PMID:25538805
NASA Technical Reports Server (NTRS)
Green, James L.; Sisson, Patricia L.
1989-01-01
Given here is an overview analysis of the Father Christmas Worm, a computer worm that was released onto the DECnet Internet three days before Christmas 1988. The purpose behind the worm was to send an electronic mail message to all users on the computer system running the worm. The message was a Christmas greeting and was signed 'Father Christmas'. From the investigation, it was determined that the worm was released from a computer (node number 20597::) at a university in Switzerland. The worm was designed to travel quickly. Estimates are that it was copied to over 6,000 computer nodes. However, it was believed to have executed on only a fraction of those computers. Within ten minutes after it was released, the worm was detected at the Space Physics Analysis Network (SPAN), NASA's largest space and Earth science network. Once the source program was captured, a procedural cure, using the existing functionality of the computer operating systems, was quickly devised and distributed. A combination of existing computer security measures, the quick and accurate procedures devised to stop copies of the worm from executing, and the network itself, were used to rapidly provide the cure. These were the main reasons why the worm executed on such a small percentage of nodes. This overview of the analysis of the events concerning the worm is based on an investigation made by the SPAN Security Team and provides some insight into future security measures that will be taken to handle computer worms and viruses that may hit similar networks.
Design and analysis of SEIQR worm propagation model in mobile internet
NASA Astrophysics Data System (ADS)
Xiao, Xi; Fu, Peng; Dou, Changsheng; Li, Qing; Hu, Guangwu; Xia, Shutao
2017-02-01
The mobile Internet has considerably facilitated daily life in recent years. However, it has become the breeding ground for lots of new worms, including the Bluetooth-based worm, the SMS/MMS-based worm and the Wi-Fi-based worm. At present, Wi-Fi is widely used for mobile devices to connect to the Internet. But it exposes these devices to the dangerous environment. Most current worm propagation models aim to solve the problems of computer worms. They cannot be used directly in the mobile environment, particularly in the Wi-Fi scenario, because of the differences between computers and mobile devices. In this paper, we propose a worm propagation model in the Wi-Fi environment, called SEIQR (Susceptible-Exposed-Infectious- Quarantined-Recovered). In the model, infected nodes can be quarantined by the Wi-Fi base station, and a new state named the Quarantined state (Q) is established to represent these infected nodes. Based on this model, we present an effective method to inhibit the spread of the Wi-Fi-based worms. Furthermore, related stabilities of the worm-free and endemic equilibriums are studied based on the basic reproduction number R0. The worm-free equilibrium is locally and globally asymptotically stable if R0 < 1, whereas the endemic equilibrium is locally asymptotically stable if R0 < 1. Finally, we evaluate the performance of our model by comprehensive experiments with different infection rates and quarantine rates. The results indicate that our mechanism can combat the worms propagated via Wi-Fi.
Towards global Guinea worm eradication in 2015: the experience of South Sudan.
Awofeso, Niyi
2013-08-01
For centuries, the Guinea worm parasite (Dracunculus medinensis) has caused disabling misery, infecting people who drink stagnant water contaminated with the worm's larvae. In 2012, there were 542 cases of Guinea worm reported globally, of which 521 (96.1%) were reported in South Sudan. Protracted civil wars, an inadequate workforce, neglect of potable water provision programs, suboptimal Guinea worm surveillance and case containment, and fragmented health systems account for many of the structural and operational factors encumbering South Sudan's Guinea worm eradication efforts. This article reviews the impacts of six established Guinea worm control strategies in South Sudan: (1) surveillance to determine actual caseload distribution and trends in response to control measures; (2) educating community members from whom worms are emerging to avoid immersing affected parts in sources of drinking water; (3) filtering potentially contaminated drinking water using cloth filters or filtered drinking straws; (4) treating potentially contaminated surface water with the copepod larvicide temephos (Abate); (5) providing safe drinking water from boreholes or hand-dug wells; and (6) containment of transmission through voluntary isolation of each patient to prevent contamination of drinking water sources, provision of first aid, and manual extraction of the worm. Surveillance, community education, potable water provision, and case containment remain weak facets of the program. Abate pesticide is not a viable option for Guinea worm control in South Sudan. In light of current case detection and containment trends, as well as capacity building efforts for Guinea worm eradication, South Sudan is more likely to eradicate Guinea worm by 2020, rather than by 2015. The author highlights areas in which substantial improvements are required in South Sudan's Guinea worm eradication program, and suggests improvement strategies. Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Wallace, W.G.; Lopez, G.R.; Levinton, J.S.
1998-01-01
It has been demonstrated that the deposit-feeding oligochaete Limnodrilus hoffmeisteri inhabiting Foundry Cove (FC), a severely cadmium (Cd)-contaminated cove located on the Hudson River, New York, USA, has evolved resistance to Cd. In this study we investigate how this resistance influences Cd trophic transfer from this oligochaete to the grass shrimp Palaemonetes pugio. Cadmium-resistant worms collected from FC and nonresistant worms collected from an adjacent unpolluted site were investigated for differences in Cd tolerance, accumulation, subcellular distribution and bioavailability to shrimp. FC worms were more tolerant of Cd, surviving twice as long as worms from the unpolluted site during a toxicity bioassay. The 7 d concentration factor of Cd-resistant worms was 4 times greater than that of nonresistant worms (2020 vs 577). There were also differences between worm populations with respect to subcellular Cd distributions. Cd-resistant worms produced metallothionein-like proteins (MT) as well as metal-rich granules (MRG) for Cd storage and detoxification; nonresistant worms only produced MT. These differences in subcellular Cd distributions led to large differences in Cd bioavailability to shrimp; shrimp fed Cd-resistant worms absorbed 21% of the ingested Cd, while those fed nonresistant worms absorbed roughly 4 times that amount (~75%). These absorption efficiencies were in good agreement with the proportions of Cd bound to the worm's most biologically available subcellular fractions (i.e. the cytosol and organelles). Although Cd-resistant worms predominantly stored the toxic metal in biologically unavailable MRG, their increased accumulation of Cd would still result in substantial trophic transfer to shrimp because of the storage of Cd in the biologically available fractions. This work demonstrates that the evolution of Cd resistance can have profound implications for Cd bioavailability and cycling within aquatic ecosystems.
Magnetic Fields of the Cerebral Cortex,
1980-06-15
with worm gears on two separate horizontal shafts . One shaft (the declination axle ) near the end of the frame rotates the dewar. The other near the...carriage is fabricated from fiberglass or wood wherever possible. Vertical movement of the dewar is permitted by a 6 cm diameter cylindrical axle of...hardwood that runs between sets of aluminum rollers having double conical shape. The axle is supported by four strands of nylon parachute cord, each
Njauw, Ching-Wei; Cheng, Chih-Yang; Ivanov, Viktor A; Khokhlov, Alexei R; Tung, Shih-Huang
2013-03-26
It has been known that the addition of bile salts to lecithin organosols induces the formation of reverse wormlike micelles and that the worms are similar to long polymer chains that entangle each other to form viscoelastic solutions. In this study, we further investigated the effects of different bile salts and bile acids on the growth of lecithin reverse worms in cyclohexane and n-decane. We utilized rheological and small-angle scattering techniques to analyze the properties and structures of the reverse micelles. All of the bile salts can transform the originally spherical lecithin reverse micelles into wormlike micelles and their rheological behaviors can be described by the single-relaxation-time Maxwell model. However, their efficiencies to induce the worms are different. In contrast, before phase separation, bile acids can induce only short cylindrical micelles that are not long enough to impart viscoelasticity. We used Fourier transform infrared spectroscopy to investigate the interactions between lecithin and bile salts/acids and found that different bile salts/acids employ different functional groups to form hydrogen bonds with lecithin. Such effects determine the relative positions of the bile salts/acids in the headgroups of lecithin, thus resulting in varying efficiencies to alter the effective critical packing parameter for the formation of wormlike micelles. This work highlights the importance of intermolecular interactions in molecular self-assembly.
Langford, Gabriel J; Janovy, John
2009-10-01
The present study used experimental infections to compare the life cycles and life histories of 6 Rhabdias spp. infecting snakes and anurans. Free-living development of anuran lungworms was primarily limited to heterogonic reproduction, and females utilized matricidal endotoky exclusively, whereas snake lungworms primarily reproduced homogonically and, when heterogonic reproduction occurred, females used a combination of releasing eggs and matricidal endotoky. Infective snake lungworms survived for longer periods in fresh water compared to anuran worms. Infective anuran lungworms penetrated into the skin of frogs and toads; few infections resulted from per os infections. In contrast, snake lungworms were unable to penetrate skin; instead, infective juveniles penetrated into snake esophageal tissue during per os infections. Despite separate points of entry, anuran and snake lungworms both migrated and developed in the fascia, eventually penetrating into the body cavity of the host. Worms molted to adulthood inside the body cavity and subsequently penetrated into the host's lungs, where they fed on blood while becoming gravid. Adult lungworm survival varied among lungworm species, but, in general, snake lungworms were longer lived than anuran worms. Anuran lungworms were poorly suited for transmission via transport hosts, whereas snake lungworms were consistently capable of establishing infections using transport hosts. Overall, these observations suggest that snake and anuran lungworms have discrepant life cycles and life history strategies.
McCabe, Gregory J.; Ault, Toby R.; Cook, Benjamin I.; Betancourt, Julio L.; Schwartz, Mark D.
2012-01-01
Detrended, modelled first leaf dates for 856 sites across North America for the period 1900–2008 are used to examine how the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) separately and together might influence the timing of spring. Although spring (mean March through April) ENSO and PDO signals are apparent in first leaf dates, the signals are not statistically significant (at a 95% confidence level (p < 0.05)) for most sites. The most significant ENSO/PDO signal in first leaf dates occurs for El Niño and positive PDO conditions. An analysis of the spatial distributions of first leaf dates for separate and combined ENSO/PDO conditions features a northwest–southeast dipole that is significantly (at p < 0.05) different than the distributions for neutral conditions. The nature of the teleconnection between Pacific SST's and first leaf dates is evident in comparable composites for detrended sea level pressure (SLP) in the spring months. During positive ENSO/PDO, there is an anomalous flow of warm air from the southwestern US into the northwestern US and an anomalous northeasterly flow of cold air from polar regions into the eastern and southeastern US. These flow patterns are reversed during negative ENSO/PDO. Although the magnitudes of first leaf date departures are not necessarily significantly related to ENSO and PDO, the spatial patterns of departures are significantly related to ENSO and PDO. These significant relations and the long-lived persistence of SSTs provide a potential tool for forecasting the tendencies for first leaf dates to be early or late.
Routes of uptake of diclofenac, fluoxetine, and triclosan into sediment-dwelling worms.
Karlsson, Maja V; Marshall, Stuart; Gouin, Todd; Boxall, Alistair B A
2016-04-01
The present study investigated the route and degree of uptake of 2 ionizable pharmaceuticals (diclofenac and fluoxetine) and 1 ionizable compound used in personal care products (triclosan) into the sediment-dwelling worm Lumbriculus variegatus. Studies were done on complete worms ("feeding") and worms where the head was absent ("nonfeeding") using (14) C-labeled ingredients. Biota sediment accumulation factors (BSAF), based on uptake of (14) C, for feeding worms increased in the order fluoxetine (0.3) < diclofenac (0.5) < triclosan (9), which is correlated with a corresponding increase in log octanol-water partition coefficient. Biota sediment accumulation factor estimates are representative of maximum values because the degree of biotransformation in the worms was not quantified. Although no significant differences were seen between the uptake of diclofenac and that of fluoxetine in feeding and nonfeeding worms, uptake of the more hydrophobic antimicrobial, triclosan, into the feeding worms was significantly greater than that in the nonfeeding worms, with the 48-h BSAF for feeding worms being 36% higher than that for the nonfeeding worms. The results imply that dietary uptake contributes to the uptake of triclosan, which may be a result of the high hydrophobicity of the compound. Models that estimate exposure of ionizable substances may need to consider uptake from both the water column and food, particularly when assessing risks from dynamic exposures to organic contaminants. © 2015 SETAC.
Locke, Anna M.; Ort, Donald R.
2014-01-01
Photosynthesis requires sufficient water transport through leaves for stomata to remain open as water transpires from the leaf, allowing CO2 to diffuse into the leaf. The leaf water needs of soybean change over time because of large microenvironment changes over their lifespan, as leaves mature in full sun at the top of the canopy and then become progressively shaded by younger leaves developing above. Leaf hydraulic conductance (K leaf), a measure of the leaf’s water transport capacity, can often be linked to changes in microenvironment and transpiration demand. In this study, we tested the hypothesis that K leaf would decline in coordination with transpiration demand as soybean leaves matured and aged. Photosynthesis (A), stomatal conductance (g s) and leaf water potential (Ψleaf) were also measured at various leaf ages with both field- and chamber-grown soybeans to assess transpiration demand. K leaf was found to decrease as soybean leaves aged from maturity to shading to senescence, and this decrease was strongly correlated with midday A. Decreases in K leaf were further correlated with decreases in g s, although the relationship was not as strong as that with A. Separate experiments investigating the response of K leaf to drought demonstrated no acclimation of K leaf to drought conditions to protect against cavitation or loss of g s during drought and confirmed the effect of leaf age in K leaf observed in the field. These results suggest that the decline of leaf hydraulic conductance as leaves age keeps hydraulic supply in balance with demand without K leaf becoming limiting to transpiration water flux. PMID:25281701
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, T.
2000-07-01
The Write One, Run Many (WORM) site (worm.csirc.net) is the on-line home of the WORM language and is hosted by the Criticality Safety Information Resource Center (CSIRC) (www.csirc.net). The purpose of this web site is to create an on-line community for WORM users to gather, share, and archive WORM-related information. WORM is an embedded, functional, programming language designed to facilitate the creation of input decks for computer codes that take standard ASCII text files as input. A functional programming language is one that emphasizes the evaluation of expressions, rather than execution of commands. The simplest and perhaps most common examplemore » of a functional language is a spreadsheet such as Microsoft Excel. The spreadsheet user specifies expressions to be evaluated, while the spreadsheet itself determines the commands to execute, as well as the order of execution/evaluation. WORM functions in a similar fashion and, as a result, is very simple to use and easy to learn. WORM improves the efficiency of today's criticality safety analyst by allowing: (1) input decks for parameter studies to be created quickly and easily; (2) calculations and variables to be embedded into any input deck, thus allowing for meaningful parameter specifications; (3) problems to be specified using any combination of units; and (4) complex mathematically defined models to be created. WORM is completely written in Perl. Running on all variants of UNIX, Windows, MS-DOS, MacOS, and many other operating systems, Perl is one of the most portable programming languages available. As such, WORM works on practically any computer platform.« less
Müller, Daniel B; Schubert, Olga T; Röst, Hannes; Aebersold, Ruedi; Vorholt, Julia A
2016-10-01
Plants are colonized by a diverse community of microorganisms, the plant microbiota, exhibiting a defined and conserved taxonomic structure. Niche separation based on spatial segregation and complementary adaptation strategies likely forms the basis for coexistence of the various microorganisms in the plant environment. To gain insights into organism-specific adaptations on a molecular level, we selected two exemplary community members of the core leaf microbiota and profiled their proteomes upon Arabidopsis phyllosphere colonization. The highly quantitative mass spectrometric technique SWATH MS was used and allowed for the analysis of over two thousand proteins spanning more than three orders of magnitude in abundance for each of the model strains. The data suggest that Sphingomonas melonis utilizes amino acids and hydrocarbon compounds during colonization of leaves whereas Methylobacterium extorquens relies on methanol metabolism in addition to oxalate metabolism, aerobic anoxygenic photosynthesis and alkanesulfonate utilization. Comparative genomic analyses indicates that utilization of oxalate and alkanesulfonates is widespread among leaf microbiota members whereas, aerobic anoxygenic photosynthesis is almost exclusively found in Methylobacteria. Despite the apparent niche separation between these two strains we also found a relatively small subset of proteins to be coregulated, indicating common mechanisms, underlying successful leaf colonization. Overall, our results reveal for two ubiquitous phyllosphere commensals species-specific adaptations to the host environment and provide evidence for niche separation within the plant microbiota. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Worm-stars and half-worms: Novel dangers and novel defense.
Hodgkin, Jonathan; Clark, Laura C; Gravato-Nobre, Maria J
2014-01-01
In a recent paper, we reported the isolation and surprising effects of two new bacterial pathogens for Caenorhabditis and related nematodes. These two pathogens belong to the genus Leucobacter and were discovered co-infecting a wild isolate of Caenorhabditis that had been collected in Cape Verde. The interactions of these bacteria with C. elegans revealed both unusual mechanisms of pathogenic attack, and an unexpected defense mechanism on the part of the worm. One pathogen, known as Verde1, is able to trap swimming nematodes by sticking their tails together, resulting in the formation of "worm-star" aggregates, within which worms are killed and degraded. Trapped larval worms, but not adults, can sometimes escape by undergoing whole-body autotomy into half-worms. The other pathogen, Verde2, kills worms by a different mechanism associated with rectal infection. Many C. elegans mutants with alterations in surface glycosylation are resistant to Verde2 infection, but hypersensitive to Verde1, being rapidly killed without worm-star formation. Conversely, surface infection of wild-type worms with Verde1 is mildly protective against Verde2. Thus, there are trade-offs in susceptibility to the two bacteria. The Leucobacter pathogens reveal novel nematode biology and provide powerful tools for exploring nematode surface properties and bacterial susceptibility.
USDA-ARS?s Scientific Manuscript database
Abscission, which is the process of organ separation, is a highly regulated process occurring as a final stage of organ development. In the tomato (Solanum lycopersicum) system, flower and leaf abscission was induced by flower removal or leaf deblading, leading to auxin depletion which results in in...
Biomass and decay rates of roots and detritus in sediments of intermittent coastal plain streams
Ken M. Fritz; Jack W. Feminella; Chris Colson; B. Graeme Lockaby; Robin Governo; Robert B. Rummer
2006-01-01
Biomass and breakdown of tree roots within streambed sediments were compared with leaf and wood detritus in three Coastal Plain headwater intermittent streams. Three separate riparian forest treatments were applied: thinned, clearcut, and reference. Biomass of roots (live and dead) and leaf/wood was significantly higher in stream banks than in the channel and declined...
Krishnamurthy, Kanakapura S; Palakurthy, Nani Babu; Yelamaggad, Channabasaveshwar V
2017-06-01
We report wormlike flexoelectric structures evolving deep in the Freedericksz state of a nematic layer of the liquid crystal cyanobiphenyl-(CH2) 7 -cyanobiphenyl. They form in the predominantly splay-bend thin boundary layers and are built up of solitary flexoelectric domains of the Bobylev-Pikin type. Their formation is possibly triggered by the gradient flexoelectric surface instability that remains optically discernible up to unusually high frequencies. The threshold voltage at which the worms form scales as square root of the frequency; in their extended state, worms often appear as labyrinthine structures on a section of loops that separate regions of opposite director deviation. Such asymmetric loops are also derived through pincement-like dissociation of ring-shaped walls. Formation of isolated domains of bulk electroconvection precedes the onset of surface instabilities. In essence, far above the Freedericksz threshold, the twisted nematic layer behaves as a combination of two orthogonally oriented planar half-layers destabilized by localized flexoelectric distortion.
21 CFR 520.45b - Albendazole paste.
Code of Federal Regulations, 2012 CFR
2012-04-01
... (Fasciola hepatica); heads and segments of tapeworms (Moniezia benedeni, M. expansa); adult and 4th stage larvae of stomach worms (brown stomach worms including 4th stage inhibited larvae (Ostertagia ostertagi); barberpole worm (Haemonchus contortus, H. placei); small stomach worm (Trichostrongylus axei)); adult and 4th...
Feng, Chenchen; Jiao, Zhengbo; Li, Shaopeng; Zhang, Yan; Bi, Yingpu
2015-12-28
We demonstrate a facile method for the rational fabrication of pore-size controlled nanoporous BiVO(4) photoanodes, and confirmed that the optimum pore-size distributions could effectively absorb visible light through light diffraction and confinement functions. Furthermore, in situ X-ray photoelectron spectroscopy (XPS) reveals more efficient photoexcited electron-hole separation than conventional particle films, induced by light confinement and rapid charge transfer in the inter-crossed worm-like structures.
NASA Technical Reports Server (NTRS)
Bartram, Peter N.
1989-01-01
The current Life Sciences Laboratory Equipment (LSLE) microcomputer for life sciences experiment data acquisition is now obsolete. Among the weaknesses of the current microcomputer are small memory size, relatively slow analog data sampling rates, and the lack of a bulk data storage device. While life science investigators normally prefer data to be transmitted to Earth as it is taken, this is not always possible. No down-link exists for experiments performed in the Shuttle middeck region. One important aspect of a replacement microcomputer is provision for in-flight storage of experimental data. The Write Once, Read Many (WORM) optical disk was studied because of its high storage density, data integrity, and the availability of a space-qualified unit. In keeping with the goals for a replacement microcomputer based upon commercially available components and standard interfaces, the system studied includes a Small Computer System Interface (SCSI) for interfacing the WORM drive. The system itself is designed around the STD bus, using readily available boards. Configurations examined were: (1) master processor board and slave processor board with the SCSI interface; (2) master processor with SCSI interface; (3) master processor with SCSI and Direct Memory Access (DMA); (4) master processor controlling a separate STD bus SCSI board; and (5) master processor controlling a separate STD bus SCSI board with DMA.
Subepidermal vesiculobullous filarial dermatitis in free-ranging American badgers (Taxidea taxus).
O'Toole, D; Williams, E S; Welch, V; Nunamaker, C E; Lynn, C
1993-07-01
Skin and superficial lymph nodes from the 65 juvenile (< 1 year old) and adult free-ranging American badgers (Taxidea taxus) of both sexes that were killed from late July to late October 1991 as part of the recovery program for the endangered black-footed ferret (Mustela nigripes) were examined for evidence of Filaria taxideae. Fifty-one badgers (51/64, 80%) were infected. Both adult badgers (30/32, 94%) and juvenile badgers (21/32, 67%) were infected by adult filarial worms, which occurred most commonly in subcutaneous tissues of the inguinal area, proximal thigh, and ventral abdomen. Sections of formalin-fixed skin and, from many badgers, subcutaneous lymph nodes were stained with hematoxylin and eosin, Jones' methenamine silver (for basement membrane), and an avidin biotin peroxidase complex method (for factor VIII-related antigen). Superficial dermatitis attributable to embryonated filarial ova and larvae was present in 26/64 badgers (41%), all of them adult (> 1 year old). Acute lesions consisted of multifocal vesiculobullous dermoepidermal separation and superficial perivascular dermatitis. Ultrastructural examination and Jones' silver-stained sections revealed separation between basal keratinocytes and the basal lamina (subepidermal vesiculation). Older lesions consisted of ulcerative superficial granulomatous dermatitis associated with ova and larvae. Multifocal granulomatous endolymphangitis, which involved afferent lymphatics of subcutaneous lymph nodes, was associated with viable as well as degenerative ova and larvae. Adult filarial worms were found in the subcutis alone and did not provoke an inflammatory reaction.
Image Segmentation of Historical Handwriting from Palm Leaf Manuscripts
NASA Astrophysics Data System (ADS)
Surinta, Olarik; Chamchong, Rapeeporn
Palm leaf manuscripts were one of the earliest forms of written media and were used in Southeast Asia to store early written knowledge about subjects such as medicine, Buddhist doctrine and astrology. Therefore, historical handwritten palm leaf manuscripts are important for people who like to learn about historical documents, because we can learn more experience from them. This paper presents an image segmentation of historical handwriting from palm leaf manuscripts. The process is composed of three steps: 1) background elimination to separate text and background by Otsu's algorithm 2) line segmentation and 3) character segmentation by histogram of image. The end result is the character's image. The results from this research may be applied to optical character recognition (OCR) in the future.
Diurnal migration of Echinostoma caproni (Digenea: Echinostomatidae) in ICR mice.
Platt, Thomas R; Graf, Emily; Kammrath, Anna; Zelmer, Derek A
2010-12-01
Twenty-four female ICR mice, 12 acclimated to a 12 ∶ 12 light-dark cycle and 12 to a 12 ∶ 12 dark-light cycle for 7 days, were each infected with 10 metacercariae of Echinostoma caproni. Infected mice were maintained on their respective lighting regimes for 28 days. Six mice (3 from each group) were necropsied at 4-hr intervals beginning at 0700 hr. The small intestine was removed, opened, and the position of individual worms and worm clusters was measured to the nearest 0.1 cm. Each intestine was subsequently divided into 20 equal segments and individual worms and worm clusters were assigned to the appropriate segment based on the original measurements. All worms were found in the posterior 55% of the intestine (ileum). All posterior segments (10-20), with the exception of segment 18, harbored at least 1 worm at some time. A Monte Carlo simulation of worm abundance in segments 10-17 over all time periods indicated a random distribution, while the same analysis of segments 10-20 indicated a non-random distribution due to large numbers of worms in segment 20 and to the absence of worms in segment 18. To analyze temporal changes in worm distribution, mice were grouped by time of necropsy as follows: night (1900 and 2300 hr), morning (0300 and 0700 hr), and day (1100 and 1500 hr). During the night and morning, E. caproni was heavily concentrated in segments 10-17 and, during the day, worms were located more posteriorly, with a heavy concentration in the last segment (20).
Protein profiling in potato (Solanum tuberosum L.) leaf tissues by differential centrifugation.
Lim, Sanghyun; Chisholm, Kenneth; Coffin, Robert H; Peters, Rick D; Al-Mughrabi, Khalil I; Wang-Pruski, Gefu; Pinto, Devanand M
2012-04-06
Foliar diseases, such as late blight, result in serious threats to potato production. As such, potato leaf tissue becomes an important substrate to study biological processes, such as plant defense responses to infection. Nonetheless, the potato leaf proteome remains poorly characterized. Here, we report protein profiling of potato leaf tissues using a modified differential centrifugation approach to separate the leaf tissues into cell wall and cytoplasmic fractions. This method helps to increase the number of identified proteins, including targeted putative cell wall proteins. The method allowed for the identification of 1484 nonredundant potato leaf proteins, of which 364 and 447 were reproducibly identified proteins in the cell wall and cytoplasmic fractions, respectively. Reproducibly identified proteins corresponded to over 70% of proteins identified in each replicate. A diverse range of proteins was identified based on their theoretical pI values, molecular masses, functional classification, and biological processes. Such a protein extraction method is effective for the establishment of a highly qualified proteome profile.
Senna leaf extracts induced Ca(+2) homeostasis in a zoonotic tapeworm Hymenolepis diminuta.
Roy, Saptarshi; Kundu, Suman; Lyndem, Larisha M
2016-10-01
Context Plants and plant products have been used in traditional medicine as anthelmintic agents in human and veterinary medicine. Three species of Senna plant, S. alata (L), S. alexandrina (M) and S. occidentalis (L.) Link (Fabaceae) have been shown to have a vermicidal/vermifugal effect on a zoonotic tapeworm Hymenolepis diminuta (Rudolphi) (Cyclophyllidean). Objective The present study validates the mode of action of these Senna plants on the parasite. The alcoholic leaf extract was determined to obtain information on the intracellular free calcium concentration level. Materials and methods Hymenolepis diminuta was maintained in Sprague-Dawley rat model for 2 months. Live parasites collected from infected rat intestine were exposed to 40 mg/mL concentration of each plant extracts prepared in phosphate buffer saline at 37 °C, till parasite gets paralyzed. The rate of efflux of calcium from the parasite tissue to the medium and the level of intracellular Ca(2+ )concentration were determined by an atomic absorption spectroscopy. Results This study revealed that exposure of the worms to the plant extract leads to disruption in intracellular calcium homeostasis. A significant increase (44.6% and 25%) of efflux in Ca(2+ )from the tissue to the incubated medium was observed. Senna alata showed high rate of efflux (5.32 mg/g) followed by S. alexandria and S. occidentalis (both 4.6 mg/g) compared with control (3.68 mg/g). Discussion and conclusion These results suggest that leaf extracts caused membrane permeability to Ca(2+ )after vacuolization of the tegument under stress and the extracts may contain compound that can be used as a chemotherapeutic agent.
High-Fidelity Modeling of Computer Network Worms
2004-06-22
plots the propagation of the TCP-based worm. This execution is among the largest TCP worm models simulated to date at packet-level. TCP vs . UDP Worm...the mapping of the virtual IP addresses to honeyd’s MAC address in the proxy’s ARP table. The proxy server listens for packets from both sides of...experimental setup, we used two ntium-4 ThinkPad , and an IBM Pentium-III ThinkPad ), running the proxy server and honeyd respectively. The Code Red II worm
Preparation and characterization of a novel adsorbent from Moringa oleifera leaf
NASA Astrophysics Data System (ADS)
Bello, Olugbenga Solomon; Adegoke, Kayode Adesina; Akinyunni, Opeyemi Omowumi
2017-06-01
A new and novel adsorbent was obtained by impregnation of Moringa oleifera leaf in H2SO4 and NaOH, respectively. Prepared adsorbents were characterized using elemental analysis, FT-IR, SEM, TGA and EDX analyses, respectively. The effects of operational parameters, such as pH, moisture content, ash content, porosity and iodine number on these adsorbents were investigated and compared with those of commercial activated carbon (CAC). EDX results of acid activated M. oleifera leaf have the highest percentage of carbon by weight (69.40 %) and (76.11 %) by atom, respectively. Proximate analysis showed that the fixed carbon content of acid activated M. oleifera leaf (69.14 ± 0.01) was the highest of all adsorbents studied. Conclusively, the present investigation shows that acid activated M. oleifera leaf is a good alternative adsorbent that could be used in lieu of CAC for recovery of dyes and heavy metal from aqueous solutions and other separation techniques.
Park, Sait Byul; Kim, Yeong Shik
2015-10-01
Senna leaf is widely consumed as tea to treat constipation or to aid in weight loss. Sennoside A, A1 , and B are dirheinanthrone glucosides that are abundant and the bioactive constituents in the plant. They are isomers that refer to the (R*R*), (S*S*), and (R*S*) forms of protons on C-10 and C-10' centers and it is difficult to refine them individually due to their structural similarities. The new separation method using counter-current chromatography successfully purified sennoside A, A1 , and B from senna leaf (Cassia acutifolia) while reversed-phase medium-pressure liquid chromatography yielded sennoside A only. n-Butanol/isopropanol/water (5:1:6, v/v/v) was selected as the solvent system for counter-current chromatography operation, and the partition coefficients were carefully determined by adding different concentrations of formic acid. High-resolution mass spectrometry and NMR spectroscopy were performed to verify the chemical properties of the compounds. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Hulme, S Elizabeth; Whitesides, George M
2011-05-16
This Review discusses the potential usefulness of the worm Caenorhabditis elegans as a model organism for chemists interested in studying living systems. C. elegans, a 1 mm long roundworm, is a popular model organism in almost all areas of modern biology. The worm has several features that make it attractive for biology: it is small (<1000 cells), transparent, and genetically tractable. Despite its simplicity, the worm exhibits complex phenotypes associated with multicellularity: the worm has differentiated cells and organs, it ages and has a well-defined lifespan, and it is capable of learning and remembering. This Review argues that the balance between simplicity and complexity in the worm will make it a useful tool in determining the relationship between molecular-scale phenomena and organism-level phenomena, such as aging, behavior, cognition, and disease. Following an introduction to worm biology, the Review provides examples of current research with C. elegans that is chemically relevant. It also describes tools-biological, chemical, and physical-that are available to researchers studying the worm. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Balqis, Ummu; Hambal, Muhammad; Rinidar; Athaillah, Farida; Ismail; Azhar; Vanda, Henni; Darmawi
2017-07-01
The objective of this research was to in vitro evaluate the cuticular surface damage of Ascaridia galli adult worms treated with ethanolic extract of betel nuts Veitchia merrillii . Phytochemical screening was done using FeCl 3 , Wagner and Dragendorff reagents, NaOH, MgHCl, and Liebermann-Burchard reaction test. Amount of 16 worms were segregated into four groups with three replicates. Four worms of each group submerged into phosphate buffered saline, 25 mg/ml, and 75 mg/ml crude ethanolic extract of V. merrillii , and 15 mg/ml albendazole. The effect of these extract was observed 40 h after incubation as soon as worms death. The worms were sectioned transversally and were explored for any cuticular histopathological changes in their body surface under microscope. We found that the ethanolic extract of V. merrillii betel nuts contains tannins, alkaloids, flavonoids, triterpenoids, and saponins. The ethanolic extract of betel nuts V. merrillii induces surface alterations caused cuticular damage of A. galli adult worms. We concluded that ethanolic extract of betel nuts V. merrillii possess anthelmintic activity caused cuticular damage of A. galli adult worms.
A calibration mechanism based on worm drive for space telescope
NASA Astrophysics Data System (ADS)
Chong, Yaqin; Li, Chuang; Xia, Siyu; Zhong, Peifeng; Lei, Wang
2017-08-01
In this paper, a new type of calibration mechanism based on worm drive is presented for a space telescope. This calibration mechanism based on worm drive has the advantages of compact size and self-lock. The mechanism mainly consists of thirty-six LEDs as the light source for flat calibration, a diffuse plate, a step motor, a worm gear reducer and a potentiometer. As the main part of the diffuse plate, a PTFE tablet is mounted in an aluminum alloy frame. The frame is fixed on the shaft of the worm gear, which is driven by the step motor through the worm. The shaft of the potentiometer is connected to that of the worm gear to measure the rotation angle of the diffuse plate through a flexible coupler. Firstly, the calibration mechanism is designed, which includes the LEDs assembly design, the worm gear reducer design and the diffuse plate assembly design. The counterweight blocks and two end stops are also designed for the diffuse plate assembly. Then a modal analysis with finite element method for the diffuse plate assembly is completed.
Inheritance of mercury tolerance in the aquatic oligochaete Tubifex tubifex.
Vidal, Dora Elva; Horne, Alex John
2003-09-01
Resistance to contaminants is an important yet unmeasured factor in sediment toxicity tests. The rate at which mercury resistance develops and its genetic persistence in the oligochaete worm Tubifex tubifex were studied under laboratory conditions. Worms were raised for four generations under two different sediment treatments, one reference clean sediment, the other contaminated with mercury. Worms raised in mercury-contaminated sediment developed mercury tolerance that persisted even when the worms were raised for three subsequent generations in clean sediment. Mercury tolerance was determined by comparative water-only toxicity tests with mercury as the only stressor. Control worms had a mean lethal concentration (LC50) of 0.18 mg/L(-1). Worms exposed to high levels of mercury in sediment had high mercury tolerance with a mean LC50 of 1.40 mg/L(-1). When mercury-tolerant and control mercury-intolerant worms were crossed, their descendants also demonstrated mercury tolerance during lethal toxicity tests. The LC50 for worm descendants resulting from this cross was 1.39 mg/L(-1). Adaptation to mercury exposures occurred rapidly in this group of worms and appears to be due to both phenotypic and genotypic mechanisms. Development of contaminant resistance and adaptation may be common phenomena in aquatic benthic invertebrates, which should be considered during the design and interpretation of toxicity tests.
Electric tempest in a teacup: The tea leaf analogy to microfluidic blood plasma separation
NASA Astrophysics Data System (ADS)
Yeo, Leslie Y.; Friend, James R.; Arifin, Dian R.
2006-09-01
In a similar fashion to Einstein's tea leaf paradox, the rotational liquid flow induced by ionic wind above a liquid surface can trap suspended microparticles by a helical motion, spinning them down towards a bottom stagnation point. The motion is similar to Batchelor [Q. J. Mech. Appl. Math. 4, 29 (1951)] flows occurring between stationary and rotating disks and arises due to a combination of the primary azimuthal and secondary bulk meridional recirculation that produces a centrifugal and enhanced inward radial force near the chamber bottom. The technology is thus useful for microfluidic particle trapping/concentration; the authors demonstrate its potential for rapid erythrocyte/blood plasma separation for miniaturized medical diagnostic kits.
Tamis, J; van Schouwenburg, G; Kleerebezem, R; van Loosdrecht, M C M
2011-11-15
Sludge predation can be an effective solution to reduce sludge production at a wastewater treatment plant. Oligochaete worms are the natural consumers of biomass in benthic layers in ecosystems. In this study the results of secondary sludge degradation by the aquatic Oligochaete worm Aulophorus furcatus in a 125 m(3) reactor and further sludge conversion in an anaerobic tank are presented. The system was operated over a period of 4 years at WWTP Wolvega, the Netherlands and was fed with secondary sludge from a low loaded activated sludge process. It was possible to maintain a stable and active population of the aquatic worm species A. furcatus during the full period. Under optimal conditions a sludge conversion of 150-200 kg TSS/d or 1.2-1.6 kg TSS/m(3)/d was established in the worm reactor. The worms grew as a biofilm on carrier material in the reactor. The surface specific conversion rate reached 140-180 g TSS/m(2)d and the worm biomass specific conversion rate was 0.5-1 g TSS sludge/g dry weight worms per day. The sludge reduction under optimal conditions in the worm reactor was 30-40%. The degradation by worms was an order of magnitude larger than the endogenous conversion rate of the secondary sludge. Effluent sludge from the worm reactor was stored in an anaerobic tank where methanogenic processes became apparent. It appeared that besides reducing the sludge amount, the worms' activity increased anaerobic digestibility, allowing for future optimisation of the total system by maximising sludge reduction and methane formation. In the whole system it was possible to reduce the amount of sludge by at least 65% on TSS basis. This is a much better total conversion than reported for anaerobic biodegradability of secondary sludge of 20-30% efficiency in terms of TSS reduction. Copyright © 2011 Elsevier Ltd. All rights reserved.
Ishikawa, N; Horii, Y; Oinuma, T; Suganuma, T; Nawa, Y
1994-01-01
The aim of this study was to examine the role of T cells on the alteration of terminal sugars of goblet cell mucins in the small intestinal mucosa of parasitized rats and to clarify the biological significance of the altered mucins in the mucosal defence against intestinal helminths. For this purpose, Nippostrongylus brasiliensis adult worms obtained from donor rats at 7 ('normal' worms) or 13 days ('damaged' worms) post-infection were implanted intraduodenally into euthymic and hypothymic (rnu/rnu) rats. Expulsion of implanted normal worms and associated goblet cell changes were extremely delayed in hypothymic recipients compared with euthymic recipients. In contrast, intraduodenally implanted damaged worms were expelled by day 5 regardless of the strains. Around the time of expulsion of implanted damaged worms, euthymic recipients showed both goblet cell hyperplasia and alteration of mucins, whereas hypothymic rats showed only the latter. Dexamethasone treatment completely abolished goblet cell changes of both strains of recipients. To clarify the importance of the constitutional changes of goblet cell mucins in mucosal defence, euthymic rats were primed by implantation of damaged worms to induce goblet cell changes, and then 3 or 5 days later they were challenged by implantation with normal worms. The results show that when goblet cell changes were induced by priming with damaged worms, recipient rats could completely prevent the establishment of normal worms. When hypothymic rats were primed and challenged in the same manner, a similar but slightly less preventive effect was observed. Such a protective effect of altered mucins seems to be selective because priming of euthymic rats with damaged N. brasiliensis did not affect the establishment of Strongyloides venezuelensis. These results suggest that: (1) once N. brasiliensis adult worms are 'damaged' by the host's T-cell-dependent immune mechanisms, they can induce alteration of sugar residues of goblet cell mucins via host-mediated, T-cell-independent processes; (2) the expression of such altered mucins is highly effective not only in causing expulsion of established damaged worms but also in preventing establishment of normal worms; and (3) the preventive effect of altered mucins is selective against parasite species. Images Figure 2 Figure 4 PMID:8206520
Angeles-Albores, David; Leighton, Daniel H W; Tsou, Tiffany; Khaw, Tiffany H; Antoshechkin, Igor; Sternberg, Paul W
2017-09-07
Understanding genome and gene function in a whole organism requires us to fully comprehend the life cycle and the physiology of the organism in question. Caenorhabditis elegans XX animals are hermaphrodites that exhaust their sperm after 3 d of egg-laying. Even though C. elegans can live for many days after cessation of egg-laying, the molecular physiology of this state has not been as intensely studied as other parts of the life cycle, despite documented changes in behavior and metabolism. To study the effects of sperm depletion and aging of C. elegans during the first 6 d of adulthood, we measured the transcriptomes of first-day adult hermaphrodites and sixth-day sperm-depleted adults, and, at the same time points, mutant fog-2(lf) worms that have a feminized germline phenotype. We found that we could separate the effects of biological aging from sperm depletion. For a large subset of genes, young adult fog-2(lf) animals had the same gene expression changes as sperm-depleted sixth-day wild-type hermaphrodites, and these genes did not change expression when fog-2(lf) females reached the sixth day of adulthood. Taken together, this indicates that changing sperm status causes a change in the internal state of the worm, which we call the female-like state. Our data provide a high-quality picture of the changes that happen in global gene expression throughout the period of early aging in the worm. Copyright © 2017 Angeles-Albores et al.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bradley, B.; Brown, D.
Biological endpoints can complement chemical analyses in monitoring environmental remediation. In some cases the levels of chemical detection are so low that the costs of clean-up to no detection would be prohibitive. And chemical tests do not indicate the availability of the contaminants to the biota. On the other hand many if not most biological tests lack specificity. The authors have investigated a protein expression assay to establish an endpoint for clean-up of sulfur mustard and breakdown products. Earthworms (Lumbricus terrestris) were exposed to sulfur mustard (SM), a breakdown product thiodiethanol (TDE), and ethylene glycol, the solvent for the twomore » chemicals. Tissue from the lining of the coelomic cavity was taken from each of 6 worms in each treatment class. Soluble proteins were extracted and separated on one and two-dimensional (1D and 2D) gels. The 1 D gels showed no difference by eye but the patterns from control and solvent control worms on 2D gels differed from those of worms exposed to TDE and SM. The 1D gel data were digitized and analyzed by pattern recognition using artificial neural networks. The protein patterns under the two treatments and the two controls were learned in one set of data and successfully recognized in a second. This indicated that what was learned was useful in recognizing patterns induced by SM and TDE. Thus a possible endpoint for remediation would be the protein pattern at no effect levels of chemicals of interest.« less
The occurrence of gizzard worms in Canada geese
Herman, C.M.; Wehr, E.E.
1954-01-01
Amidostomum anseris, a roundworm which occurs under the horny lining of the gizzard in birds, is a widely distributed parasite in Canada geese. It is also reported from snow geese (Chen hyperborea). Although the extent of erosion of the gizzard wall by these worms is not precisely correlated with the number of worms present, it is usually severe in Canada geese when 150 or more worms are present. Gizzard worm infection is considered a contributing factor to low weights, poor condition and to losses among the Canada geese which winter at the Pea Island National Wildlife Refuge in North Carolina. The mean number of gizzard worms per bird is considerably higher for Pea Island than for areas where winter losses have not been reported.
The WRKY transcription factor family and senescence in switchgrass.
Rinerson, Charles I; Scully, Erin D; Palmer, Nathan A; Donze-Reiner, Teresa; Rabara, Roel C; Tripathi, Prateek; Shen, Qingxi J; Sattler, Scott E; Rohila, Jai S; Sarath, Gautam; Rushton, Paul J
2015-11-09
Early aerial senescence in switchgrass (Panicum virgatum) can significantly limit biomass yields. WRKY transcription factors that can regulate senescence could be used to reprogram senescence and enhance biomass yields. All potential WRKY genes present in the version 1.0 of the switchgrass genome were identified and curated using manual and bioinformatic methods. Expression profiles of WRKY genes in switchgrass flag leaf RNA-Seq datasets were analyzed using clustering and network analyses tools to identify both WRKY and WRKY-associated gene co-expression networks during leaf development and senescence onset. We identified 240 switchgrass WRKY genes including members of the RW5 and RW6 families of resistance proteins. Weighted gene co-expression network analysis of the flag leaf transcriptomes across development readily separated clusters of co-expressed genes into thirteen modules. A visualization highlighted separation of modules associated with the early and senescence-onset phases of flag leaf growth. The senescence-associated module contained 3000 genes including 23 WRKYs. Putative promoter regions of senescence-associated WRKY genes contained several cis-element-like sequences suggestive of responsiveness to both senescence and stress signaling pathways. A phylogenetic comparison of senescence-associated WRKY genes from switchgrass flag leaf with senescence-associated WRKY genes from other plants revealed notable hotspots in Group I, IIb, and IIe of the phylogenetic tree. We have identified and named 240 WRKY genes in the switchgrass genome. Twenty three of these genes show elevated mRNA levels during the onset of flag leaf senescence. Eleven of the WRKY genes were found in hotspots of related senescence-associated genes from multiple species and thus represent promising targets for future switchgrass genetic improvement. Overall, individual WRKY gene expression profiles could be readily linked to developmental stages of flag leaves.
Parameterization of Forest Canopies with the PROSAIL Model
NASA Astrophysics Data System (ADS)
Austerberry, M. J.; Grigsby, S.; Ustin, S.
2013-12-01
Particularly in forested environments, arboreal characteristics such as Leaf Area Index (LAI) and Leaf Inclination Angle have a large impact on the spectral characteristics of reflected radiation. The reflected spectrum can be measured directly with satellites or airborne instruments, including the MASTER and AVIRIS instruments. This particular project dealt with spectral analysis of reflected light as measured by AVIRIS compared to tree measurements taken from the ground. Chemical properties of leaves including pigment concentrations and moisture levels were also measured. The leaf data was combined with the chemical properties of three separate trees, and served as input data for a sequence of simulations with the PROSAIL Model, a combination of PROSPECT and Scattering by Arbitrarily Inclined Leaves (SAIL) simulations. The output was a computed reflectivity spectrum, which corresponded to the spectra that were directly measured by AVIRIS for the three trees' exact locations within a 34-meter pixel resolution. The input data that produced the best-correlating spectral output was then cross-referenced with LAI values that had been obtained through two entirely separate methods, NDVI extraction and use of the Beer-Lambert law with airborne LiDAR. Examination with regressive techniques between the measured and modeled spectra then enabled a determination of the trees' probable structure and leaf parameters. Highly-correlated spectral output corresponded well to specific values of LAI and Leaf Inclination Angle. Interestingly, it appears that varying Leaf Angle Distribution has little or no noticeable effect on the PROSAIL model. Not only is the effectiveness and accuracy of the PROSAIL model evaluated, but this project is a precursor to direct measurement of vegetative indices exclusively from airborne or satellite observation.
Ribeiro da Luz, Beatriz; Crowley, James K.
2007-01-01
In contrast to visible and short-wave infrared data, thermal infrared spectra of broad leaf plants show considerable spectral diversity, suggesting that such data eventually could be utilized to map vegetation composition. However, remotely measuring the subtle emissivity features of leaves still presents major challenges. To be successful, sensors operating in the 8–14 μm atmospheric window must have high signal-to-noise and a small enough instantaneous field of view to allow measurements of only a few leaf surfaces. Methods for atmospheric compensation, temperature–emissivity separation, and spectral feature analysis also will need to be refined to allow the recognition, and perhaps, exploitation of leaf thermal infrared spectral properties.
Mazza, Carlos A.; Zavala, Jorge; Scopel, Ana L.; Ballaré, Carlos L.
1999-01-01
Most of our present knowledge about the impacts of solar UVB radiation on terrestrial ecosystems comes from studies with plants. Recently, the effects of UVB on the growth and survival of consumer species have begun to receive attention, but very little is known about UVB impacts on animal behavior. Here we report that manipulations of the flux of solar UVB received by field-grown soybean crops had large and consistent effects on the density of the thrips (Caliothrips phaseoli, Thysanoptera: Thripidae) populations that invaded the canopies, as well as on the amount of leaf damage caused by the insects. Solar UVB strongly reduced thrips herbivory. Thrips not only preferred leaves from plants that were not exposed to solar UVB over leaves from UVB-exposed plants in laboratory and field choice experiments, but they also appeared to directly sense and avoid exposure to solar UVB. Additional choice experiments showed that soybean leaf consumption by the late-season soybean worm Anticarsia gemmatalis (Lepidoptera: Noctuidae) was much less intense in leaves with even slight symptoms of an early thrips attack than in undamaged leaves. These experiments suggest that phytophagous insects can present direct and indirect behavioral responses to solar UVB. The indirect responses are mediated by changes in the plant host that are induced by UVB and, possibly, by other insects whose behavior is affected by UVB. PMID:9927679
Balqis, Ummu; Hambal, Muhammad; Rinidar; Athaillah, Farida; Ismail; Azhar; Vanda, Henni; Darmawi
2017-01-01
Aim: The objective of this research was to in vitro evaluate the cuticular surface damage of Ascaridia galli adult worms treated with ethanolic extract of betel nuts Veitchia merrillii. Materials and Methods: Phytochemical screening was done using FeCl3, Wagner and Dragendorff reagents, NaOH, MgHCl, and Liebermann–Burchard reaction test. Amount of 16 worms were segregated into four groups with three replicates. Four worms of each group submerged into phosphate buffered saline, 25 mg/ml, and 75 mg/ml crude ethanolic extract of V. merrillii, and 15 mg/ml albendazole. The effect of these extract was observed 40 h after incubation as soon as worms death. The worms were sectioned transversally and were explored for any cuticular histopathological changes in their body surface under microscope. Results: We found that the ethanolic extract of V. merrillii betel nuts contains tannins, alkaloids, flavonoids, triterpenoids, and saponins. The ethanolic extract of betel nuts V. merrillii induces surface alterations caused cuticular damage of A. galli adult worms. Conclusion: We concluded that ethanolic extract of betel nuts V. merrillii possess anthelmintic activity caused cuticular damage of A. galli adult worms. PMID:28831213
Inequalities in body size among mermithid nematodes parasitizing earwigs.
Maure, Fanny; Poulin, Robert
2016-12-01
Variation among body sizes of adult parasitic worms determines the relative genetic contribution of individuals to the next generation as it affects the effective parasite population size. Here, we investigate inequalities in body size and how they are affected by intensity of infection in Mermis nigrescens (Mermithidae: Nematoda) parasitizing the European earwig Forficula auricularia in New Zealand. Among a population of pre-adult worms prior to their emergence from the host, we observed only modest inequalities in body length; however, among worms sharing the same individual host, inequalities in body sizes decreased with increasing intensity of infection. Thus, the more worms occurred in a host, the more the second-longest, third-longest and even fourth-longest worms approached the longest worm in body length. This pattern, also known from another mermithid species, suggests that worms sharing the same host may have infected it roughly simultaneously, when the host encountered a clump of eggs in the environment. Thus, the life history and mode of infection of the parasite may explain the modest inequalities in the sizes achieved by pre-adult worms, which are lower than those reported for endoparasitic helminths of vertebrates.
NASA Technical Reports Server (NTRS)
Litvin, Faydor L.; Nava, Alessandro; Fan, Qi; Fuentes, Alfonso
2002-01-01
New geometry of face worm gear drives with conical and cylindrical worms is proposed. The generation of the face worm-gear is based on application of a tilted head-cutter (grinding tool) instead of application of a hob applied at present. The generation of a conjugated worm is based on application of a tilted head-cutter (grinding tool) as well. The bearing contact of the gear drive is localized and is oriented longitudinally. A predesigned parabolic function of transmission errors for reduction of noise and vibration is provided. The stress analysis of the gear drive is performed using a three-dimensional finite element analysis. The contacting model is automatically generated. The developed theory is illustrated with numerical examples.
NASA Astrophysics Data System (ADS)
Janeček, Štěpán; Lepš, Jan
2005-09-01
The effects of litter removal, leaf cover of established plants and cover of basal internodes of a dominant species Molinia caerulea on seedling germination and the dynamics of established plants were studied in a field experiment in an oligotrophic wet meadow. Although the negative influence of litter on total seedling number and seedling species composition was non-significant, litter significantly affected the dynamics of the established vegetation and caused inhibition of total leaf cover development. The effects of total leaf cover of established plants on seedling establishment changed during the vegetation season. Whereas the effect of total leaf cover was positive at the start and in the middle of the vegetation season, at the end the total leaf cover negatively affected seedling establishment. Both total leaf cover and cover of basal internodes affected seedling composition. Effects of these two variables were statistically separable suggesting that they are based on different mechanisms. The response of seedling establishment to these factors was species specific and, consequently, our data support the hypothesis that that biotically generated spatial heterogeneity can promote species co-existence through the differentiation of species regeneration niches.
Kaminsky, Ronald; Rufener, Lucien; Bouvier, Jacques; Lizundia, Regina; Schorderet Weber, Sandra; Sager, Heinz
2013-08-01
Worm infections can cause severe harm and death to both humans and numerous domestic and wild animals. Despite the fact that there are many beneficial worm species, veterinarians, physicians and parasitologists have multiple reasons to combat parasitic worms. The pros and cons of various approaches for the discovery of new control methods are discussed, including novel anthelmintics, vaccines and genetic approaches to identify novel drug and vaccine targets. Currently, the mainstay of worm control remains chemotherapy and prophylaxis. The importance of knowledgeable and wise use of the available anthelmintics is highlighted. Copyright © 2013 Elsevier B.V. All rights reserved.
Periorbital dirofilariasis—Clinical and imaging findings: Live worm on ultrasound
Gopinath, Thandre N; Lakshmi, K P; Shaji, P C; Rajalakshmi, P C
2013-01-01
Ocular dirofilariasis is a zoonotic filariasis caused by nematode worm,Dirofilaria. We present a case of dirofilariasis affecting the upper eyelid in a 2-year-old child presenting as an acutely inflammed cyst, from southern Indian state of Kerala. Live adult worm was surgically removed and confirmed to be Dirofilaria repens. Live worm showing continuous movement was seen on the pre-operative high-resolution ultrasound. Ultrasound can be helpful in pre-operative identification of live worm. Imaging findings reported in literature are very few. We describe the clinical, ultrasound, and magnetic resonance imaging (MRI) findings. PMID:23803483
Malisie, A F; Prihandrijanti, M; Otterpohl, R
2007-01-01
Human excreta (faeces and urine) contribute only a small volume in domestic wastewater but are one of the main causes of water pollution. On the other hand, they contain very valuable nutrients to be reused as anthropogenic fertiliser through proper collection, treatment and hygienisation processes. To know the potential of nutrient recovery and reuse in Indonesia, a pilot scale source separation domestic wastewater system has been built in Surabaya and, so far, has shown promising results. Using urine diverting toilets, up to 86% nitrogen, 21% phosphorus and 69% potassium from urine and 12% of nitrogen, 68% of phosphorus and 20% of potassium from the faecal matter can be recovered. The separated urine was stored for 6 months before usage as fertiliser for hygienic reasons, while the separated faecal matter was composted with worms (vermicomposting). In order to investigate the fertilising effect, a preliminary cultivation experiment has been carried out on young rose plants using different fertilisers for 2 months.
Reich, Peter B; Falster, Daniel S; Ellsworth, David S; Wright, Ian J; Westoby, Mark; Oleksyn, Jacek; Lee, Tali D
2009-01-01
* Here, we evaluated how increased shading and declining net photosynthetic capacity regulate the decline in net carbon balance with increasing leaf age for 10 Australian woodland species. We also asked whether leaves at the age of their mean life-span have carbon balances that are positive, zero or negative. * The net carbon balances of 2307 leaves on 53 branches of the 10 species were estimated. We assessed three-dimensional architecture, canopy openness, photosynthetic light response functions and dark respiration rate across leaf age sequences on all branches. We used YPLANT to estimate light interception and to model carbon balance along the leaf age sequences. * As leaf age increased to the mean life-span, increasing shading and declining photosynthetic capacity each separately reduced daytime carbon gain by approximately 39% on average across species. Together, they reduced daytime carbon gain by 64% on average across species. * At the age of their mean life-span, almost all leaves had positive daytime carbon balances. These per leaf carbon surpluses were of a similar magnitude to the estimated whole-plant respiratory costs per leaf. Thus, the results suggest that a whole-plant economic framework, including respiratory costs, may be useful in assessing controls on leaf longevity.
Modeling the electrophoretic separation of short biological molecules in nanofluidic devices
NASA Astrophysics Data System (ADS)
Fayad, Ghassan; Hadjiconstantinou, Nicolas
2010-11-01
Via comparisons with Brownian Dynamics simulations of the worm-like-chain and rigid-rod models, and the experimental results of Fu et al. [Phys. Rev. Lett., 97, 018103 (2006)], we demonstrate that, for the purposes of low-to-medium field electrophoretic separation in periodic nanofilter arrays, sufficiently short biomolecules can be modeled as point particles, with their orientational degrees of freedom accounted for using partition coefficients. This observation is used in the present work to build a particularly simple and efficient Brownian Dynamics simulation method. Particular attention is paid to the model's ability to quantitatively capture experimental results using realistic values of all physical parameters. A variance-reduction method is developed for efficiently simulating arbitrarily small forcing electric fields.
Study on beta-galactosidase enzymatic activity of herbal yogurt.
Chowdhury, Banani Ray; Chakraborty, Runu; Raychaudhuri, Utpal
2008-03-01
Different types of herbal yogurts were developed by mixing standardized milk with pretreated herbs, namely tulsi leaf (Ocimum sanctum), pudina leaf (Mentha arvensis) and coriander leaf (Coriandrum sativum), with leaves separately and a 1:1 (v/v) mixture of the strains of lactic starter cultures---Lactobacillus acidophilus (NCIM 2903) and Lactobacillus plantarum (NCIM 2083)-followed by incubation at 40 degrees C for 6 h. The beta-galactosidase enzymatic activity of the abovementioned herbal yogurts was determined and interestingly noted to exhibit higher enzymatic activity compared with the control yogurt (without any herbs). Among all herbal yogurts, tulsi yogurt had the maximum beta-galactosidase activity.
Dai, Caili; Yan, Zhihu; You, Qing; Du, Mingyong; Zhao, Mingwei
2014-01-01
Through the descriptive and rheological characterization of worm-like micelles formed by N-hexadecyl-N-methylpyrrolidinium bromide and sodium laurate, the formation and properties of the worm-like micelles were affected by the concentrations of sodium laurate and temperature. Additionally, cryogenic transmission electron microscopy images further validated the formation of worm-like micelles. PMID:25019152
Worm Burden-Dependent Disruption of the Porcine Colon Microbiota by Trichuris suis Infection
Wu, Sitao; Li, Robert W.; Li, Weizhong; Beshah, Ethiopia; Dawson, Harry D.; Urban, Joseph F.
2012-01-01
Helminth infection in pigs serves as an excellent model for the study of the interaction between human malnutrition and parasitic infection and could have important implications in human health. We had observed that pigs infected with Trichuris suis for 21 days showed significant changes in the proximal colon microbiota. In this study, interactions between worm burden and severity of disruptions to the microbial composition and metabolic potentials in the porcine proximal colon microbiota were investigated using metagenomic tools. Pigs were infected by a single dose of T. suis eggs for 53 days. Among infected pigs, two cohorts were differentiated that either had adult worms or were worm-free. Infection resulted in a significant change in the abundance of approximately 13% of genera detected in the proximal colon microbiota regardless of worm status, suggesting a relatively persistent change over time in the microbiota due to the initial infection. A significant reduction in the abundance of Fibrobacter and Ruminococcus indicated a change in the fibrolytic capacity of the colon microbiota in T. suis infected pigs. In addition, ∼10% of identified KEGG pathways were affected by infection, including ABC transporters, peptidoglycan biosynthesis, and lipopolysaccharide biosynthesis as well as α-linolenic acid metabolism. Trichuris suis infection modulated host immunity to Campylobacter because there was a 3-fold increase in the relative abundance in the colon microbiota of infected pigs with worms compared to naïve controls, but a 3-fold reduction in worm-free infected pigs compared to controls. The level of pathology observed in infected pigs with worms compared to worm-free infected pigs may relate to the local host response because expression of several Th2-related genes were enhanced in infected pigs with worms versus those worm-free. Our findings provided insight into the dynamics of the proximal colon microbiota in pigs in response to T. suis infection. PMID:22532855
Oldham, Alana R; Sillett, Stephen C; Tomescu, Alexandru M F; Koch, George W
2010-07-01
Leaves at the tops of most trees are smaller, thicker, and in many other ways different from leaves on the lowermost branches. This height-related variation in leaf structure has been explained as acclimation to differing light environments and, alternatively, as a consequence of hydrostatic, gravitational constraints on turgor pressure that reduce leaf expansion. • To separate hydrostatic effects from those of light availability, we used anatomical analysis of height-paired samples from the inner and outer tree crowns of tall redwoods (Sequoia sempervirens). • Height above the ground correlates much more strongly with leaf anatomy than does light availability. Leaf length, width, and mesophyll porosity all decrease linearly with height and help explain increases in leaf-mass-to-area ratio and decreases in both photosynthetic capacity and internal gas-phase conductance with increasing height. Two functional traits-leaf thickness and transfusion tissue-also increase with height and may improve water-stress tolerance. Transfusion tissue area increases enough that whole-leaf vascular volume does not change significantly with height in most trees. Transfusion tracheids become deformed with height, suggesting they may collapse under water stress and act as a hydraulic buffer that improves leaf water status and reduces the likelihood of xylem dysfunction. • That such variation in leaf structure may be caused more by gravity than by light calls into question use of the terms "sun" and "shade" to describe leaves at the tops and bottoms of tall tree crowns.
Fourier-Based Diffraction Analysis of Live Caenorhabditis elegans.
Magnes, Jenny; Hastings, Harold M; Raley-Susman, Kathleen M; Alivisatos, Clara; Warner, Adam; Hulsey-Vincent, Miranda
2017-09-13
This manuscript describes how to classify nematodes using temporal far-field diffraction signatures. A single C. elegans is suspended in a water column inside an optical cuvette. A 632 nm continuous wave HeNe laser is directed through the cuvette using front surface mirrors. A significant distance of at least 20-30 cm traveled after the light passes through the cuvette ensures a useful far-field (Fraunhofer) diffraction pattern. The diffraction pattern changes in real time as the nematode swims within the laser beam. The photodiode is placed off-center in the diffraction pattern. The voltage signal from the photodiode is observed in real time and recorded using a digital oscilloscope. This process is repeated for 139 wild type and 108 "roller" C. elegans. Wild type worms exhibit a rapid oscillation pattern in solution. The "roller" worms have a mutation in a key component of the cuticle that interferes with smooth locomotion. Time intervals that are not free of saturation and inactivity are discarded. It is practical to divide each average by its maximum to compare relative intensities. The signal for each worm is Fourier transformed so that the frequency pattern for each worm emerges. The signal for each type of worm is averaged. The averaged Fourier spectra for the wild type and the "roller" C. elegans are distinctly different and reveal that the dynamic worm shapes of the two different worm strains can be distinguished using Fourier analysis. The Fourier spectra of each worm strain match an approximate model using two different binary worm shapes that correspond to locomotory moments. The envelope of the averaged frequency distribution for actual and modeled worms confirms the model matches the data. This method can serve as a baseline for Fourier analysis for many microscopic species, as every microorganism will have its unique Fourier spectrum.
Value-Range Analysis of C Programs
NASA Astrophysics Data System (ADS)
Simon, Axel
In 1988, Robert T. Morris exploited a so-called buffer-overflow bug in finger (a dæmon whose job it is to return information on local users) to mount a denial-of-service attack on hundreds of VAX and Sun-3 computers [159]. He created what is nowadays called a worm; that is, a crafted stream of bytes that, when sent to a computer over the network, utilises a buffer-overflow bug in the software of that computer to execute code encoded in the byte stream. In the case of a worm, this code will send the very same byte stream to other computers on the network, thereby creating an avalanche of network traffic that ultimately renders the network and all computers involved in replicating the worm inaccessible. Besides duplicating themselves, worms can alter data on the host that they are running on. The most famous example in recent years was the MSBlaster32 worm, which altered the configuration database on many Microsoft Windows machines, thereby forcing the computers to reboot incessantly. Although this worm was rather benign, it caused huge damage to businesses who were unable to use their IT infrastructure for hours or even days after the appearance of the worm. A more malicious worm is certainly conceivable [187] due to the fact that worms are executed as part of a dæmon (also known as "service" on Windows machines) and thereby run at a privileged level, allowing access to any data stored on the remote computer. While the deletion of data presents a looming threat to valuable information, even more serious uses are espionage and theft, in particular because worms do not have to affect the running system and hence may be impossible to detect.
Mobile Transactional Modelling: From Concepts to Incremental Knowledge
NASA Astrophysics Data System (ADS)
Launders, Ivan; Polovina, Simon; Hill, Richard
In 1988, Robert T. Morris exploited a so-called buffer-overflow bug in finger (a dæmon whose job it is to return information on local users) to mount a denial-of-service attack on hundreds of VAX and Sun-3 computers [159]. He created what is nowadays called a worm; that is, a crafted stream of bytes that, when sent to a computer over the network, utilises a buffer-overflow bug in the software of that computer to execute code encoded in the byte stream. In the case of a worm, this code will send the very same byte stream to other computers on the network, thereby creating an avalanche of network traffic that ultimately renders the network and all computers involved in replicating the worm inaccessible. Besides duplicating themselves, worms can alter data on the host that they are running on. The most famous example in recent years was the MSBlaster32 worm, which altered the configuration database on many Microsoft Windows machines, thereby forcing the computers to reboot incessantly. Although this worm was rather benign, it caused huge damage to businesses who were unable to use their IT infrastructure for hours or even days after the appearance of the worm. A more malicious worm is certainly conceivable [187] due to the fact that worms are executed as part of a dæmon (also known as "service" on Windows machines) and thereby run at a privileged level, allowing access to any data stored on the remote computer. While the deletion of data presents a looming threat to valuable information, even more serious uses are espionage and theft, in particular because worms do not have to affect the running system and hence may be impossible to detect.
De-worming school children and hygiene intervention.
Luong, T V
2003-06-01
Helminths or worm infestations refer to worms that live as parasites in the human body and are a fundamental cause of disease associated with health and nutrition problems beyond gastrointestinal tract disturbances. Globally, over 3.5 billion people are infected with intestinal worms, of which 1.47 billion are with roundworm, 1.3 billion people with hookworm and 1.05 billion with whipworm. School children aged 5 - 15 years suffer the highest infection rate and worm burden that attributes to poor sanitation and hygiene. About 400 million school-age children are infected with roundworm, whipworm and hookworm worldwide, a large proportion of whom are found in the East Asia region (Cambodia, China, Lao PDR, Thailand and Vietnam). These parasites consume nutrients from children they infect, thus retarding their physical development. They destroy tissues and organs, cause abdominal pain, diarrhoea, intestinal obstruction, anaemia, ulcers and other health problems. All of these consequences of infection can slow cognitive development and thus impair learning. De-worming school children by anthelmintic drug treatment is a curative approach for expelling the heavy worm load. However, drug therapy alone is only a short-term measure of reducing worm infection and re-infection is frequent. Control measures through improved sanitation, hygiene and de-worming are needed to prevent infection and re-infection. UNICEF has supported many governments in this (and other) regions to assist in the provision of water supply and sanitary facilities and intensive hygiene education in many schools through the Water, Environment and Sanitation (WES) programme. The UNICEF supported school sanitation and hygiene education (SSHE) programme, and other programmes, could effectively enhance behaviour change in children to break the routes of worm transmission and other waterborne diseases.
Assessment of Agroforestry Trees in Dry-land Savanna Supports Ecohydrologic Separation
NASA Astrophysics Data System (ADS)
Ceperley, Natalie; Mande, Theophile; Van de Giesen, Nick; Tyler, Scott; Parlange, Marc
2016-04-01
We use stable isotopes of water to demonstrate the ecohydrologic separation, or the plant controlled compartmentalization, of different water sources in a catchment in South Eastern Burkina Faso. We analyze water extracted from the groundwater, stream water, precipitation, perched aquifer, xylem water of agroforestry trees, and sub-canopy soil water over a 6 year period to explore how the separation affects different components of the system over time. The ratio between deuterium and O18 allows us to assess whether the water that plants use is the same as the water that recharges the aquifer and runs off in the stream. Water extracted from the tree at leaf out in February corresponded to deuterium and O18 concentrations of the groundwater, a drop from its dry season, enriched, levels which mimicked the soil water. Examination of the isotopic signature suggests that the size of tree plays an important role in duration and timing of this leaf-out as well as the degree of enrichment during the peak of the dry season. Dates of leaf out were confirmed by analyzing sub-canopy radiation and photographs. Water extracted from roots suggests that the trees are performing hydraulic redistribution, or lifting the ground water and 'sharing it' with the rooting zone soil during the dry season. The enriched level of xylem, in this case, is a product of water loss and enrichment along the travel path of the water from the roots to the tip of the branch, as evidenced by the variation according to size of tree. Vapor pressure deficit, sap flow, soil water, and soil moisture interactions support this picture of interacting controls, separate from hydrologic triggers on the water movement in the tree. A second round of sampling focused on the leaf out period by extracting and analyzing stem water from throughout the canopy during the leaf out. Simultaneous large eddy correlation revealed high levels of latent energy flux, even during the dry season. Our isotope analysis allowed us to conclude that tree level transpiration explains this discrepancy since it does not access the same reservoirs of water as the rest of the catchment. Most current land surface models do not differentiate between different reservoirs of water.
Scanning electron microscopy of Strongylus spp. in zebra.
Els, H J; Malan, F S; Scialdo-Krecek, R C
1983-12-01
The external ultrastructure of the anterior and posterior extremities of the nematodes, Strongylus asini , Strongylus vulgaris, Strongylus equinus and Strongylus edentatus, was studied with scanning electron microscopy (SEM). Fresh specimens of S. asini were collected from the caecum, ventral colon and vena portae of Equus burchelli and Equus zebra hartmannae ; S. vulgaris from the caecum, colon and arteria ileocolica of E. burchelli ; S. equinus from the ventral colon of E. z. hartmannae and S. edentatus from the caecum and ventral colon of both zebras , during surveys of parasites in zebras in the Etosha Game Reserve, South West Africa/Namibia, and the Kruger National Park, Republic of South Africa. The worms were cleaned, fixed and mounted by standard methods and photographed in a JEOL JSM - 35C scanning electron microscope (SEM) operating at 12kV . The SEM showed the following differences: the tips of the external leaf-crowns varied and were fine and delicate in S. asini , coarse and broad in S. vulgaris and, in S. equinus and S. edentatus, closely adherent, separating into single elements for half their length. The excretory pores showed only slight variation, and the morphology of the copulatory bursae did not differ from those seen with light microscopy. The genital cones differed markedly: S. asini had a ventral triangular projection and laterally 2 finger-like projections: in S. vulgaris there were numerous bosses on the lateral and ventral aspects of the cone; in S. equinus 2 finger-like processes projected laterocaudally ; and in S. edentatus 2 pairs of papilla-like processes projected laterally on the ventral aspects, and a pair of rounded projections and a pair of hair-like structures adorned the dorsal aspects.(ABSTRACT TRUNCATED AT 250 WORDS)
Fluorescence hyperspectral imaging technique for foreign substance detection on fresh-cut lettuce.
Mo, Changyeun; Kim, Giyoung; Kim, Moon S; Lim, Jongguk; Cho, Hyunjeong; Barnaby, Jinyoung Yang; Cho, Byoung-Kwan
2017-09-01
Non-destructive methods based on fluorescence hyperspectral imaging (HSI) techniques were developed to detect worms on fresh-cut lettuce. The optimal wavebands for detecting the worms were investigated using the one-way ANOVA and correlation analyses. The worm detection imaging algorithms, RSI-I (492-626)/492 , provided a prediction accuracy of 99.0%. The fluorescence HSI techniques indicated that the spectral images with a pixel size of 1 × 1 mm had the best classification accuracy for worms. The overall results demonstrate that fluorescence HSI techniques have the potential to detect worms on fresh-cut lettuce. In the future, we will focus on developing a multi-spectral imaging system to detect foreign substances such as worms, slugs and earthworms on fresh-cut lettuce. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
A genetic analysis of Trichuris trichiura and Trichuris suis from Ecuador.
Meekums, Hayley; Hawash, Mohamed B F; Sparks, Alexandra M; Oviedo, Yisela; Sandoval, Carlos; Chico, Martha E; Stothard, J Russell; Cooper, Philip J; Nejsum, Peter; Betson, Martha
2015-03-19
Since the nematodes Trichuris trichiura and T. suis are morphologically indistinguishable, genetic analysis is required to assess epidemiological cross-over between people and pigs. This study aimed to clarify the transmission biology of trichuriasis in Ecuador. Adult Trichuris worms were collected during a parasitological survey of 132 people and 46 pigs in Esmeraldas Province, Ecuador. Morphometric analysis of 49 pig worms and 64 human worms revealed significant variation. In discriminant analysis morphometric characteristics correctly classified male worms according to host species. In PCR-RFLP analysis of the ribosomal Internal Transcribed Spacer (ITS-2) and 18S DNA (59 pig worms and 82 human worms), nearly all Trichuris exhibited expected restriction patterns. However, two pig-derived worms showed a "heterozygous-type" ITS-2 pattern, with one also having a "heterozygous-type" 18S pattern. Phylogenetic analysis of the mitochondrial large ribosomal subunit partitioned worms by host species. Notably, some Ecuadorian T. suis clustered with porcine Trichuris from USA and Denmark and some with Chinese T. suis. This is the first study in Latin America to genetically analyse Trichuris parasites. Although T. trichiura does not appear to be zoonotic in Ecuador, there is evidence of genetic exchange between T. trichiura and T. suis warranting more detailed genetic sampling.
Liu, J; Chappell, L H
1998-01-01
To study the action mode of cyclosporin A (CsA) against Schistosoma mansoni in vitro. MF1 mice were infected with Schistosoma mansoni cercariae for 6 weeks when the adult worms were recovered by portal perfusion. The male worms of S. mansoni recovered were exposed to varying concentrations of CsA at 8, 16, and 24 h in vitro. Drug induced damage to the male worm surface was chrono-biologically observed throughout these experiments by SEM. After the male worms of S. mansoni were incubated with 1 microgram/ml CsA for 8-24 h, the tegument showed swelling of ridges with appearance of holes on their surface and detachment of a part of spines. The above damage of the tegument became more evident in male worms after incubation with 10, 15, 20 micrograms/ml CsA for 8-24 h. Moreover, incubation of male worms with 25 micrograms/ml CsA for 8-24 h resulted in significant deformation and disruption of tegument, rupture of ridges and detachment of spines. The tegumental damage of male worms of S. mansoni was dose- and time-dependent. The antischistosomal action of CsA is direct, the schistosome tegument appears to be the main site for CsA attack.
Mwanga, Joseph R; Kaatano, Godfrey M; Siza, Julius E; Chang, Su Young; Ko, Yunsuk; Kullaya, Cyril M; Nsabo, Jackson; Eom, Keeseon S; Yong, Tai-Soon; Chai, Jong-Yil; Min, Duk-Young; Rim, Han-Jong; Changalucha, John M
2015-10-01
Schistosomiasis and intestinal worm infections are widespread diseases of public health importance in Tanzania. A study on perceptions and practices related to schistosomiasis and intestinal worm infections was undertaken among a community population of Kome Island in Sengerema District, north-western Tanzania, where intestinal schistosomiasis and intestinal worm infections are endemic. Schistosomiasis and intestinal worm-related perceptions and practices were assessed before and 3 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention as a control measure. Data were obtained from baseline and post-intervention knowledge, attitudes, and practices (KAP) questionnaire surveys conducted twice in 2009 and 2012 among 82 individuals aged ≥15 years. We found significant increases in respondents' knowledge of the cause, transmission, symptoms, health consequences, and prevention of schistosomiasis and intestinal worm infections after PHAST intervention. The increase in respondents' knowledge on almost all aspects of the said infections was translated into actions to control schistosomiasis and intestinal worm infections. This has not been achieved by chance, but due to well-designed and locally-adapted PHAST intervention. We conclude that despite criticisms, PHAST approach is still useful in empowering communities to control water, sanitation, and hygiene related infectious diseases such as schistosomiasis and intestinal worm infections.
Centralization of the deuterostome nervous system predates chordates.
Nomaksteinsky, Marc; Röttinger, Eric; Dufour, Héloïse D; Chettouh, Zoubida; Lowe, Chris J; Martindale, Mark Q; Brunet, Jean-François
2009-08-11
The origin of the chordate central nervous system (CNS) is unknown. One theory is that a CNS was present in the first bilaterian and that it gave rise to both the ventral cord of protostomes and the dorsal cord of deuterostomes. Another theory proposes that the chordate CNS arose by a dramatic process of dorsalization and internalization from a diffuse nerve net coextensive with the skin of the animal, such as enteropneust worms (Hemichordata, Ambulacraria) are supposed to have. We show here that juvenile and adult enteropneust worms in fact have a bona fide CNS, i.e., dense agglomerations of neurons associated with a neuropil, forming two cords, ventral and dorsal. The latter is internalized in the collar as a chordate-like neural tube. Contrary to previous assumptions, the greater part of the adult enteropneust skin is nonneural, although elements of the peripheral nervous system (PNS) are found there. We use molecular markers to show that several neuronal types are anatomically segregated in the CNS and PNS. These neuroanatomical features, whatever their homologies with the chordate CNS, imply that nervous system centralization predates the evolutionary separation of chordate and hemichordate lineages.
Mech, L.D.
2008-01-01
Examination of 110 Mink (Mustela vison) carcasses from 1998 through 2007 indicated that the giant kidney worm, Dioctophyma renale, occurred in Pine and Kanabec Counties of eastern Minnesota with annual prevalences of 0-92%. Worm prevalence increased from 20% in 1999 to 92% in 2001 and decreased to 6% in 2005. During 2000 to 2007, no worms were found in Mink from Anoka and Chisago Counties (n = 54), and in 2000, none in 107 Mink from LeSeur, Freeborn, Redwood, Brown and Watonwan Counties. Changes in kidney worm prevalence were positively related to trapping success, considered an index of Mink density.
Propagation Modeling and Defending of a Mobile Sensor Worm in Wireless Sensor and Actuator Networks.
Wang, Tian; Wu, Qun; Wen, Sheng; Cai, Yiqiao; Tian, Hui; Chen, Yonghong; Wang, Baowei
2017-01-13
WSANs (Wireless Sensor and Actuator Networks) are derived from traditional wireless sensor networks by introducing mobile actuator elements. Previous studies indicated that mobile actuators can improve network performance in terms of data collection, energy supplementation, etc. However, according to our experimental simulations, the actuator's mobility also causes the sensor worm to spread faster if an attacker launches worm attacks on an actuator and compromises it successfully. Traditional worm propagation models and defense strategies did not consider the diffusion with a mobile worm carrier. To address this new problem, we first propose a microscopic mathematical model to describe the propagation dynamics of the sensor worm. Then, a two-step local defending strategy (LDS) with a mobile patcher (a mobile element which can distribute patches) is designed to recover the network. In LDS, all recovering operations are only taken in a restricted region to minimize the cost. Extensive experimental results demonstrate that our model estimations are rather accurate and consistent with the actual spreading scenario of the mobile sensor worm. Moreover, on average, the LDS outperforms other algorithms by approximately 50% in terms of the cost.
Metals and terrestrial earthworms (Annelida: Oligochaeta)
Beyer, W.N.
1981-01-01
The toxicity of metals to earthworms and the residues of metals found in earthworms are reviewed. Meta 1 concentrations are rarely high enough to be toxic to worms, but copper may reduce populations in orchards heavily treated with fungicides and in soil contaminated with pig wastes. The metals in some industrial sewage sludges may interfere with using sludge in vermiculture. Storage ratios (the concentration of a metal in worms divided by the concentration in soil) tend to be highest in infertile soil and lowest in media rich in organic matter, such as sewage sludge. Cadmium, gold, and selenium are highly concentrated by worms. Lead concentrations in worms may be very high, but are generally lower than concentrations in soil. Body burdens of both copper and zinc seem to be regulated by worms. Because worms are part of the food webs of many wildlife species, and also because they are potentially valuable feed supplements for domestic animals, the possible toxic effects of cadmium and other metals should be studied. Worms can make metals more available to food webs and can redistribute them in soil.
Zhou, Jun; Sun, Jiang Bing; Xu, Xin Yu; Cheng, Zhao Hui; Zeng, Ping; Wang, Feng Qiao; Zhang, Qiong
2015-03-25
A simple, inexpensive and efficient method based on the mixed cloud point extraction (MCPE) combined with high performance liquid chromatography was developed for the simultaneous separation and determination of six flavonoids (rutin, hyperoside, quercetin-3-O-sophoroside, isoquercitrin, astragalin and quercetin) in Apocynum venetum leaf samples. The non-ionic surfactant Genapol X-080 and cetyl-trimethyl ammonium bromide (CTAB) was chosen as the mixed extracting solvent. Parameters that affect the MCPE processes, such as the content of Genapol X-080 and CTAB, pH, salt content, extraction temperature and time were investigated and optimized. Under the optimized conditions, the calibration curve for six flavonoids were all linear with the correlation coefficients greater than 0.9994. The intra-day and inter-day precision (RSD) were below 8.1% and the limits of detection (LOD) for the six flavonoids were 1.2-5.0 ng mL(-1) (S/N=3). The proposed method was successfully used to separate and determine the six flavonoids in A. venetum leaf samples. Copyright © 2015 Elsevier B.V. All rights reserved.
Paulus, Stefan; Dupuis, Jan; Riedel, Sebastian; Kuhlmann, Heiner
2014-01-01
Due to the rise of laser scanning the 3D geometry of plant architecture is easy to acquire. Nevertheless, an automated interpretation and, finally, the segmentation into functional groups are still difficult to achieve. Two barley plants were scanned in a time course, and the organs were separated by applying a histogram-based classification algorithm. The leaf organs were represented by meshing algorithms, while the stem organs were parameterized by a least-squares cylinder approximation. We introduced surface feature histograms with an accuracy of 96% for the separation of the barley organs, leaf and stem. This enables growth monitoring in a time course for barley plants. Its reliability was demonstrated by a comparison with manually fitted parameters with a correlation R2 = 0.99 for the leaf area and R2 = 0.98 for the cumulated stem height. A proof of concept has been given for its applicability for the detection of water stress in barley, where the extension growth of an irrigated and a non-irrigated plant has been monitored. PMID:25029283
1992-09-01
example, grain size had no effect , while the number of worms added to each expo- sure vessel was critical. Direct transfer from 30 ppt to salinities !515... Effect of Salinity on Juvenile Worms ..................... 13 Effect of Ammonia on Juvenile Worms .................... 14 Resistance of Juvenile Worms to...experimental design used to evaluate salinity effects . Preliminary experiments indicated that nominal ammonia concentrations (0, 2.5, 5.0, 10, 20, and
The research of hourglass worm dynamic balancing simulation based on SolidWorks motion
NASA Astrophysics Data System (ADS)
Wang, Zhuangzhuang; Yang, Jie; Liu, Pingyi; Zhao, Junpeng
2018-02-01
Hourglass worm is extensively used in industry due to its characteristic of heavy-load and a large reduction ratio. Varying sizes of unbalanced mass distribution appeared in the design of a single head worm. With machines developing towards higher speed and precision, the vibration and shock caused by the unbalanced mass distribution of rotating parts must be considered. Therefore, the balance grade of these parts must meet higher requirements. A method based on theoretical analysis and SolidWorks motion software simulation is presented in this paper; the virtual dynamic balance simulation test of the hourglass worm was carried out during the design of the product, so as to ensure that the hourglass worm meet the requirements of dynamic balance in the design process. This can effectively support the structural design of the hourglass worm and provide a way of thinking and designing the same type of products.
Nirmala, Intan R; Trees; Suwarni; Pramono, Mochammad S
2017-06-01
The sago worm Rhynchophorus ferrugineus is a nutritious food source found in the remaining parts of a sago palm trunk after the removal of sago starch by farmers. The effort to increase sago worm consumption is investigated in an intervention study among children aged <5 years. Children aged 1-5 years were allocated to a sago worm inclusive diet (n=10) and to a control group eating a usual diet, but without sago worms (n=13). Snacks were served once per day (100 g) for 45 days and designed to contain similar amounts of vegetables (carrots and long beans) and other ingredients including rice, sticky rice, cassava, sweet potato, banana, or tofu with or without sago worms. Food preference was ascertained by interview. Anthropometric measurements were taken at baseline and the endpoint. After mixing all food stuffs into one product for instance nasi gurih, protein and fat content in the intervention group was higher compared to control group (8.8 g and 7.3 g vs 4.7 g and 0.5 g respectively). In the intervention group receiving complementary feeding with sago worms, children's height changed minimally as did the control group (0.3 vs 0.2 cm); no difference was observed between the groups regarding weight or height. Sago worm consumption can diversify the diet through usage in various dishes, so improving its overall nutritional quality. Worm addition in an intervention program does not compromise, but maintains nutritional value. Local use adds affordability and sustainability to the food and health systems in a sago-consuming culture, so contributing to food security.
Roussel, Nicolas; Sprenger, Jeff; Tappan, Susan J; Glaser, Jack R
2014-01-01
The behavior of the well-characterized nematode, Caenorhabditis elegans (C. elegans), is often used to study the neurologic control of sensory and motor systems in models of health and neurodegenerative disease. To advance the quantification of behaviors to match the progress made in the breakthroughs of genetics, RNA, proteins, and neuronal circuitry, analysis must be able to extract subtle changes in worm locomotion across a population. The analysis of worm crawling motion is complex due to self-overlap, coiling, and entanglement. Using current techniques, the scope of the analysis is typically restricted to worms to their non-occluded, uncoiled state which is incomplete and fundamentally biased. Using a model describing the worm shape and crawling motion, we designed a deformable shape estimation algorithm that is robust to coiling and entanglement. This model-based shape estimation algorithm has been incorporated into a framework where multiple worms can be automatically detected and tracked simultaneously throughout the entire video sequence, thereby increasing throughput as well as data validity. The newly developed algorithms were validated against 10 manually labeled datasets obtained from video sequences comprised of various image resolutions and video frame rates. The data presented demonstrate that tracking methods incorporated in WormLab enable stable and accurate detection of these worms through coiling and entanglement. Such challenging tracking scenarios are common occurrences during normal worm locomotion. The ability for the described approach to provide stable and accurate detection of C. elegans is critical to achieve unbiased locomotory analysis of worm motion. PMID:26435884
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dorfman, D.
Earthworms can live in soils containing high quantities of mercury, lead, and zinc. The worms (Lumbricus terrestris) concentrate these heavy metals in their tissues. The use of these worms to reduce the quantities of mercury and other heavy metals in soils may be practical. In July, 1993, a preliminary study was made using earthworms and soils with differing amounts of mercury, The quantities were 0.0 grams, 0.5 grams, and 1.0 grams of mercury as mercuric chloride. Earthworms were placed into these soils for two or more weeks, then harvested. The worms were rinsed with deionized water, then dissolved in nitricmore » acid. Each sample was prepared for analysis with the addition of HNO{sub 3}, H{sub 2}SO{sub 4}, potassium permanganate, and hydrozylamine hydrochloride. A Jerome Instrument gold foil analyzer was used to determine levels of mercury after volatilizing the sample with stannous chloride. Worms exposed to contaminated soils remove 50 to 1,400 times as much mercury as do worms in control soils. In a hypothetical case, a site contaminated with one pound of mercury, 1,000 to 45,000 worms would be required to reduce mercury levels to background levels in the soil (about 250 ppb). After harvesting worms in contaminated soil they could be dried (90% of their weight is water), and the mercury regained by chemical processes. Soil conducive to earthworm survival is required. This includes a well aerated loamy soil, proper pH (7.0), and periodic watering and feeding. There are several methods of harvesting worms, including flooding and electricity. Large numbers of worms can be obtained from commercial growers.« less
Bah, Germanus S.; Ward, Emma L.; Srivastava, Abhishek; Trees, Alexander J.; Tanya, Vincent N.
2014-01-01
Onchocerciasis (river blindness), caused by the filarial nematode Onchocerca volvulus, is a major cause of visual impairment and dermatitis in sub-Saharan Africa. As O. volvulus contains an obligatory bacterial symbiont (Wolbachia), it is susceptible to antibiotic chemotherapy, although current regimens are considered too prolonged for community-level control programs. The aim of this study was to compare the efficacies of oxytetracycline and rifampin, administered separately or in combination, against a close relative of O. volvulus (Onchocerca ochengi) in cattle. Six animals per group were treated with continuous or intermittent oxytetracycline regimens, and effects on adult worm viability, dermal microfilarial loads, and Wolbachia density in worm tissues were assessed. Subsequently, the efficacies of 3-week regimens of oxytetracycline and rifampin alone and a combination regimen were compared, and rifampin levels in plasma and skin were quantified. A 6-month regimen of oxytetracycline with monthly dosing was strongly adulticidal, while 3-week and 6-week regimens exhibited weaker adulticidal effects. However, all three regimens achieved >2-log reductions in microfilarial load. In contrast, rifampin monotherapy and oxytetracycline-rifampin duotherapy failed to induce substantive reductions in either adult worm burden or microfilarial load, although a borderline effect on Wolbachia density was observed following duotherapy. Dermal rifampin levels were maintained above the MIC for >24 h after a single intravenous dose. We conclude that oxytetracycline-rifampin duotherapy is less efficacious against O. ochengi than oxytetracycline alone. Further studies will be required to determine whether rifampin reduces oxytetracycline bioavailability in this system, as suggested by human studies using other tetracycline-rifampin combinations. PMID:24247133
Bah, Germanus S; Ward, Emma L; Srivastava, Abhishek; Trees, Alexander J; Tanya, Vincent N; Makepeace, Benjamin L
2014-01-01
Onchocerciasis (river blindness), caused by the filarial nematode Onchocerca volvulus, is a major cause of visual impairment and dermatitis in sub-Saharan Africa. As O. volvulus contains an obligatory bacterial symbiont (Wolbachia), it is susceptible to antibiotic chemotherapy, although current regimens are considered too prolonged for community-level control programs. The aim of this study was to compare the efficacies of oxytetracycline and rifampin, administered separately or in combination, against a close relative of O. volvulus (Onchocerca ochengi) in cattle. Six animals per group were treated with continuous or intermittent oxytetracycline regimens, and effects on adult worm viability, dermal microfilarial loads, and Wolbachia density in worm tissues were assessed. Subsequently, the efficacies of 3-week regimens of oxytetracycline and rifampin alone and a combination regimen were compared, and rifampin levels in plasma and skin were quantified. A 6-month regimen of oxytetracycline with monthly dosing was strongly adulticidal, while 3-week and 6-week regimens exhibited weaker adulticidal effects. However, all three regimens achieved >2-log reductions in microfilarial load. In contrast, rifampin monotherapy and oxytetracycline-rifampin duotherapy failed to induce substantive reductions in either adult worm burden or microfilarial load, although a borderline effect on Wolbachia density was observed following duotherapy. Dermal rifampin levels were maintained above the MIC for >24 h after a single intravenous dose. We conclude that oxytetracycline-rifampin duotherapy is less efficacious against O. ochengi than oxytetracycline alone. Further studies will be required to determine whether rifampin reduces oxytetracycline bioavailability in this system, as suggested by human studies using other tetracycline-rifampin combinations.
S. W. Robinson; John C. Moser; M. S. Blum; E. Amante
1974-01-01
Interspecific trail following activity of poison sac contents from four species of leaf-cutting ants was investigated. with only one exception, all the species teste followed trails made from each others poison sac contents. however when the ants were given a choice of following one of two separate trails, clear differences were shown in the poison sac contents of the...
Vinca drug components accumulate exclusively in leaf exudates of Madagascar periwinkle
Roepke, Jonathan; Salim, Vonny; Wu, Maggie; Thamm, Antje M. K.; Murata, Jun; Ploss, Kerstin; Boland, Wilhelm; De Luca, Vincenzo
2010-01-01
The monoterpenoid indole alkaloids (MIAs) of Madagascar periwinkle (Catharanthus roseus) continue to be the most important source of natural drugs in chemotherapy treatments for a range of human cancers. These anticancer drugs are derived from the coupling of catharanthine and vindoline to yield powerful dimeric MIAs that prevent cell division. However the precise mechanisms for their assembly within plants remain obscure. Here we report that the complex development-, environment-, organ-, and cell-specific controls involved in expression of MIA pathways are coupled to secretory mechanisms that keep catharanthine and vindoline separated from each other in living plants. Although the entire production of catharanthine and vindoline occurs in young developing leaves, catharanthine accumulates in leaf wax exudates of leaves, whereas vindoline is found within leaf cells. The spatial separation of these two MIAs provides a biological explanation for the low levels of dimeric anticancer drugs found in the plant that result in their high cost of commercial production. The ability of catharanthine to inhibit the growth of fungal zoospores at physiological concentrations found on the leaf surface of Catharanthus leaves, as well as its insect toxicity, provide an additional biological role for its secretion. We anticipate that this discovery will trigger a broad search for plants that secrete alkaloids, the biological mechanisms involved in their secretion to the plant surface, and the ecological roles played by them. PMID:20696903
Edwards, Gerald E.; Black, Clanton C.
1971-01-01
A technique is described for the separation of mesophyll and bundle sheath cells from Digitaria sanguinalis leaves and evidence for separation is given with light and scanning electron micrographs. Gentle grinding of fully differentiated leaves in a mortar releases mesophyll cells which are isolated on nylon nets by filtration. More extensive grinding of the remaining tissue yields bundle sheath strands which are isolated by filtration with stainless steel sieves and nylon nets. Further grinding of bundle sheath strands in a tissue homogenizer releases bundle sheath cells which are collected on nylon nets. Percentage of purity derived from cell counts and yield data on a chlorophyll basis are given. The internal leaf cell morphology is presented in scanning electron micrographs and compared with light micrographs of fully-differentiated D. sanguinalis leaves. In leaves of plants which possess the C4-dicarboxylic acid cycle of photosynthesis, the relationship of leaf morphology to photosynthesis in mesophyll and bundle sheath cells is considered, and the hypothesis is presented that as atmospheric CO2 enters a leaf about 85% is fixed by the C4-dicarboxylic acid cycle in the mesophyll cells and 10 to 15% is fixed by the reductive pentose phosphate cycle in the bundle sheath cells. A technique also is given for the isolation of mesophyll cells from spinach leaves. Images PMID:16657571
Edwards, G E; Black, C C
1971-01-01
A technique is described for the separation of mesophyll and bundle sheath cells from Digitaria sanguinalis leaves and evidence for separation is given with light and scanning electron micrographs. Gentle grinding of fully differentiated leaves in a mortar releases mesophyll cells which are isolated on nylon nets by filtration. More extensive grinding of the remaining tissue yields bundle sheath strands which are isolated by filtration with stainless steel sieves and nylon nets. Further grinding of bundle sheath strands in a tissue homogenizer releases bundle sheath cells which are collected on nylon nets. Percentage of purity derived from cell counts and yield data on a chlorophyll basis are given.The internal leaf cell morphology is presented in scanning electron micrographs and compared with light micrographs of fully-differentiated D. sanguinalis leaves. In leaves of plants which possess the C(4)-dicarboxylic acid cycle of photosynthesis, the relationship of leaf morphology to photosynthesis in mesophyll and bundle sheath cells is considered, and the hypothesis is presented that as atmospheric CO(2) enters a leaf about 85% is fixed by the C(4)-dicarboxylic acid cycle in the mesophyll cells and 10 to 15% is fixed by the reductive pentose phosphate cycle in the bundle sheath cells.A technique also is given for the isolation of mesophyll cells from spinach leaves.
Burrowing by small polychaetes - mechanics, behavior and muscle structure of Capitella sp.
Grill, Susann; Dorgan, Kelly M
2015-05-15
Worms of different sizes extend burrows through muddy sediments by fracture, applying dorso-ventral forces that are amplified at the crack tip. Smaller worms displace sediments less than larger worms and therefore are limited in how much force they can apply to burrow walls. We hypothesized that small worms would exhibit a transition in burrowing mechanics, specifically a lower limit in body size for the ability to burrow by fracture, corresponding with an ontogenetic transition in muscle morphology. Kinematics of burrowing in a mud analog, external morphology and muscle arrangement were examined in juveniles and adults of the small polychaete Capitella sp. We found that it moves by peristalsis, and no obvious differences were observed among worms of different sizes; even very small juveniles were able to burrow through a clear mud analog by fracture. Interestingly, we found that in addition to longitudinal and circular muscles needed for peristaltic movements, left- and right-handed helical muscles wrap around the thorax of worms of all sizes. We suggest that in small worms helical muscles may function to supplement forces generated by longitudinal muscles and to maintain hydrostatic pressure, enabling higher forces to be exerted on the crack wall. Further research is needed, however, to determine whether surficial sediments inhabited by small worms fail by fracture or plastically deform under forces of the magnitudes applied by Capitella sp. © 2015. Published by The Company of Biologists Ltd.
Ede, Alison Okorie; Nwaokoro, Joakin Chidozie; Iwuala, C C; Amadi, A N; Akpelu, Ugochinyere Alvana
2014-10-01
Guinea worm is a parasite found in unprotected drinking water sources, causes considerable morbidity and loss of agricultural production among rural people. The study was to determine the current status of Guinea worm infection in Ezza North and to evaluate the impact of control measures on guinea worm infection. A total of 200 individuals in Ezza North Southeastern, Nigeria were examined for guinea worm infection. A standardized questionnaire was used to determine the effect of potable water on guinea worm eradication/control, the source of drinking water, information on the knowledge, attitude, symptom management practices, availability of health facilities and boreholes installation status. The instrument for data collection was well constructed, validated and reliable tested questionnaire by an expert. Data obtained was analyzed using Epi-Info model 3.4 versions. Results of a study indicated majority of the respondents 195 (97.5 %) have access to safe drinking water supply which indicated no case of Guinea worm infection. The active use of potable water supply was found among the age group of 20-30 years 71 (35.5 %) and higher in male (57.5 %) than females (42.5 %). The drastic reduction of Guinea worm infection to zero (0) level in Ezza North were due to multiple factors as health education, availability of functional boreholes, presence of health centers for immediate treatment if any case discovered.
Promoting positive health behaviours--'tooth worm' phenomenon and its implications.
Gao, X L; Hsu, C Y S; Xu, Y C; Loh, T; Koh, D; Hwarng, H B
2012-03-01
'Tooth worm' is a traditional belief about the pathogen of dental caries (tooth decay). Nevertheless, in our previous study, parental 'tooth worm' belief was linked to a reduced caries risk of their children. This study aimed to further characterize the impact of parental 'tooth worm' belief on their children's caries experience and its psychobehavioural mechanisms. analytic observational study. Thirteen randomly selected kindergartens in Singapore. 1,782 preschoolers aged 3-6 years. Each child received an oral examination and microbiological tests. Parents completed a self-administered questionnaire on their socio-demographic background, oral health knowledge/attitude and child's oral health habits. Multivariate analysis confirmed a reduced chance of 'high caries rate' (number of affected teeth > 2) among children whose parents held the 'tooth worm' belief (Odds Ratio = 0.41; 95% Confidence Interval = 0.19-0.89). With such perception among parents, children brushed their teeth more frequently (p = 0.042). Since no difference in oral hygiene was observed, the health benefit of the "tooth worm" perception may be acquired through the delivery of fluoride (an agent with proven anti-caries effect) during frequent toothbrushing episodes. This study revealed a 'tooth worm' phenomenon, indicating that parental 'tooth worm' belief is associated with early establishment of regular toothbrushing habit and reduction of dental caries in children. This phenomenon and its psychobehavioural mechanisms, enriching our understanding of oral health behaviours, have implications for effective health education.
Separation of abscission zone cells in detached Azolla roots depends on apoplastic pH.
Fukuda, Kazuma; Yamada, Yoshiya; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji
2013-01-01
In studies on the mechanism of cell separation during abscission, little attention has been paid to the apoplastic environment. We found that the apoplastic pH surrounding abscission zone cells in detached roots of the water fern Azolla plays a major role in cell separation. Abscission zone cells of detached Azolla roots were separated rapidly in a buffer at neutral pH and slowly in a buffer at pH below 4.0. However, cell separation rarely occurred at pH 5.0-5.5. Light and electron microscopy revealed that cell separation was caused by a degradation of the middle lamella between abscission zone cells at both pH values, neutral and below 4.0. Low temperature and papain treatment inhibited cell separation. Enzyme(s) in the cell wall of the abscission zone cells might be involved in the degradation of the pectin of the middle lamella and the resultant, pH-dependent cell separation. By contrast, in Phaseolus leaf petioles, unlike Azolla roots, cell separation was slow and increased only at acidic pH. The rapid cell separation, as observed in Azolla roots at neutral pH, did not occur. Indirect immunofluorescence microscopy, using anti-pectin monoclonal antibodies, revealed that the cell wall pectins of the abscission zone cells of Azolla roots and Phaseolus leaf petioles looked similar and changed similarly during cell separation. Thus, the pH-related differences in cell separation mechanisms of Azolla and Phaseolus might not be due to differences in cell wall pectin, but to differences in cell wall-located enzymatic activities responsible for the degradation of pectic substances. A possible enzyme system is discussed. Copyright © 2012 Elsevier GmbH. All rights reserved.
A Physiological and Behavioral Mechanism for Leaf Herbivore-Induced Systemic Root Resistance1[OPEN
Erb, Matthias; Robert, Christelle A.M.; Marti, Guillaume; Lu, Jing; Doyen, Gwladys R.; Villard, Neil; Barrière, Yves; Wolfender, Jean-Luc; Turlings, Ted C.J.
2015-01-01
Indirect plant-mediated interactions between herbivores are important drivers of community composition in terrestrial ecosystems. Among the most striking examples are the strong indirect interactions between spatially separated leaf- and root-feeding insects sharing a host plant. Although leaf feeders generally reduce the performance of root herbivores, little is known about the underlying systemic changes in root physiology and the associated behavioral responses of the root feeders. We investigated the consequences of maize (Zea mays) leaf infestation by Spodoptera littoralis caterpillars for the root-feeding larvae of the beetle Diabrotica virgifera virgifera, a major pest of maize. D. virgifera strongly avoided leaf-infested plants by recognizing systemic changes in soluble root components. The avoidance response occurred within 12 h and was induced by real and mimicked herbivory, but not wounding alone. Roots of leaf-infested plants showed altered patterns in soluble free and soluble conjugated phenolic acids. Biochemical inhibition and genetic manipulation of phenolic acid biosynthesis led to a complete disappearance of the avoidance response of D. virgifera. Furthermore, bioactivity-guided fractionation revealed a direct link between the avoidance response of D. virgifera and changes in soluble conjugated phenolic acids in the roots of leaf-attacked plants. Our study provides a physiological mechanism for a behavioral pattern that explains the negative effect of leaf attack on a root-feeding insect. Furthermore, it opens up the possibility to control D. virgifera in the field by genetically mimicking leaf herbivore-induced changes in root phenylpropanoid patterns. PMID:26430225
The impact of various distance between axes of worm gear on torque value. Worm gear test stand
NASA Astrophysics Data System (ADS)
Sobek, M.; Baier, A.; Grabowski, Ł.
2017-08-01
Transferring both rotational and translational movements in systems used in the automotive industry is a very important and complex issue. In addition, the situation becomes much more difficult and complicated when the design of the transition system requires a high precision of operation as well as a well definite and long operating life. Such requirements are imposed on all components of today’s motor vehicles. However, particular attention is paid to the elements that directly or indirectly affect the safety of persons traveling in the vehicle. Such components are undoubtedly components included as parts of the steering system of the vehicle. Power steering systems have been present in motor vehicles for more than a century. They go through continuous metamorphosis and they are getting better and better. Current power steering systems are based on an electric motor and some kind of transmission. Depending on the position of the drive relative to the steering column, different configurations of the transmission are used. This article will cover issues related to tests of power steering gearing using a worm drive. The worm drive is a very specific example of a propulsion system that uses twisted axles. Normally, in this type of transition you can find two gear units with the axis mounted with a 90° angle between. The components of the worm drive are a worm and a worm gear, also called a worm wheel. In terms of the geometrical form, the worm resembles a helical spur gear. The shape of the worm is similar to the shape of a screw with a trapezoidal thread. A correct matching of these two components ensures proper operation of the entire transmission. Incorrect positioning of the components in relation to each other can significantly reduce the lifetime of the drive unit, and also lead to abnormal work, eg by raising the noise level. This article describes a test method of finding the appropriate distance between the axles of both worm drive units by testing the torque change during gear operation.
NASA Technical Reports Server (NTRS)
Sun, D. C.; Yuan, Qin
1995-01-01
The geometrical parameters for a wormgear intended to be used as the transmission in advanced helicopters are finalized. The resulting contact pattern of the meshing tooth surfaces is suitable for the implementation of hydrostatic lubrication Fluid film lubrication of the contact is formulated considering external pressurization as well as hydrodynamic wedge and squeeze actions. The lubrication analysis is aimed at obtaining the oil supply pressure needed to separate the worm and gear surfaces by a prescribed minimum film thickness. The procedure of solving the mathematical problem is outlined.
Genomic Dissection of Leaf Angle in Maize (Zea mays L.) Using a Four-Way Cross Mapping Population.
Ding, Junqiang; Zhang, Luyan; Chen, Jiafa; Li, Xiantang; Li, Yongming; Cheng, Hongliang; Huang, Rongrong; Zhou, Bo; Li, Zhimin; Wang, Jiankang; Wu, Jianyu
2015-01-01
Increasing grain yield by the selection for optimal plant architecture has been the key focus in modern maize breeding. As a result, leaf angle, an important determinant of plant architecture, has been significantly improved to adapt to the ever-increasing plant density in maize production over the past several decades. To extend our understanding on the genetic mechanisms of leaf angle in maize, we developed the first four-way cross mapping population, consisting of 277 lines derived from four maize inbred lines with varied leaf angles. The four-way cross mapping population together with the four parental lines were evaluated for leaf angle in two environments. In this study, we reported linkage maps built in the population and quantitative trait loci (QTL) on leaf angle detected by inclusive composite interval mapping (ICIM). ICIM applies a two-step strategy to effectively separate the cofactor selection from the interval mapping, which controls the background additive and dominant effects at the same time. A total of 14 leaf angle QTL were identified, four of which were further validated in near-isogenic lines (NILs). Seven of the 14 leaf angle QTL were found to overlap with the published leaf angle QTL or genes, and the remaining QTL were unique to the four-way population. This study represents the first example of QTL mapping using a four-way cross population in maize, and demonstrates that the use of specially designed four-way cross is effective in uncovering the basis of complex and polygenetic trait like leaf angle in maize.
Genomic Dissection of Leaf Angle in Maize (Zea mays L.) Using a Four-Way Cross Mapping Population
Li, Xiantang; Li, Yongming; Cheng, Hongliang; Huang, Rongrong; Zhou, Bo; Li, Zhimin; Wang, Jiankang; Wu, Jianyu
2015-01-01
Increasing grain yield by the selection for optimal plant architecture has been the key focus in modern maize breeding. As a result, leaf angle, an important determinant of plant architecture, has been significantly improved to adapt to the ever-increasing plant density in maize production over the past several decades. To extend our understanding on the genetic mechanisms of leaf angle in maize, we developed the first four-way cross mapping population, consisting of 277 lines derived from four maize inbred lines with varied leaf angles. The four-way cross mapping population together with the four parental lines were evaluated for leaf angle in two environments. In this study, we reported linkage maps built in the population and quantitative trait loci (QTL) on leaf angle detected by inclusive composite interval mapping (ICIM). ICIM applies a two-step strategy to effectively separate the cofactor selection from the interval mapping, which controls the background additive and dominant effects at the same time. A total of 14 leaf angle QTL were identified, four of which were further validated in near-isogenic lines (NILs). Seven of the 14 leaf angle QTL were found to overlap with the published leaf angle QTL or genes, and the remaining QTL were unique to the four-way population. This study represents the first example of QTL mapping using a four-way cross population in maize, and demonstrates that the use of specially designed four-way cross is effective in uncovering the basis of complex and polygenetic trait like leaf angle in maize. PMID:26509792
Müller-Linow, Mark; Pinto-Espinosa, Francisco; Scharr, Hanno; Rascher, Uwe
2015-01-01
Three-dimensional canopies form complex architectures with temporally and spatially changing leaf orientations. Variations in canopy structure are linked to canopy function and they occur within the scope of genetic variability as well as a reaction to environmental factors like light, water and nutrient supply, and stress. An important key measure to characterize these structural properties is the leaf angle distribution, which in turn requires knowledge on the 3-dimensional single leaf surface. Despite a large number of 3-d sensors and methods only a few systems are applicable for fast and routine measurements in plants and natural canopies. A suitable approach is stereo imaging, which combines depth and color information that allows for easy segmentation of green leaf material and the extraction of plant traits, such as leaf angle distribution. We developed a software package, which provides tools for the quantification of leaf surface properties within natural canopies via 3-d reconstruction from stereo images. Our approach includes a semi-automatic selection process of single leaves and different modes of surface characterization via polygon smoothing or surface model fitting. Based on the resulting surface meshes leaf angle statistics are computed on the whole-leaf level or from local derivations. We include a case study to demonstrate the functionality of our software. 48 images of small sugar beet populations (4 varieties) have been analyzed on the base of their leaf angle distribution in order to investigate seasonal, genotypic and fertilization effects on leaf angle distributions. We could show that leaf angle distributions change during the course of the season with all varieties having a comparable development. Additionally, different varieties had different leaf angle orientation that could be separated in principle component analysis. In contrast nitrogen treatment had no effect on leaf angles. We show that a stereo imaging setup together with the appropriate image processing tools is capable of retrieving the geometric leaf surface properties of plants and canopies. Our software package provides whole-leaf statistics but also a local estimation of leaf angles, which may have great potential to better understand and quantify structural canopy traits for guided breeding and optimized crop management.
Maternal hookworm modifies risk factors for childhood eczema: results from a birth cohort in Uganda
Mpairwe, Harriet; Ndibazza, Juliet; Webb, Emily L; Nampijja, Margaret; Muhangi, Lawrence; Apule, Barbara; Lule, Swaib; Akurut, Hellen; Kizito, Dennison; Kakande, Mohammed; Jones, Frances M; Fitzsimmons, Colin M; Muwanga, Moses; Rodrigues, Laura C; Dunne, David W; Elliott, Alison M
2014-01-01
Background Worms may protect against allergy. Early-life worm exposure may be critical, but this has not been fully investigated. Objectives To investigate whether worms in pregnancy and in early childhood are associated with childhood eczema incidence. Methods The Entebbe Mother and Baby Study, an anthelminthic treatment trial, enrolled pregnant women between 2003 and 2005 in Uganda. Mothers were investigated for worms during pregnancy and children annually. Eczema was doctor-diagnosed from birth to age five years. A planned observational analysis was conducted within the trial cohort to investigate associations between worms and eczema. Results Data for 2345 live-born children were analysed. Hookworm was the most prevalent maternal worm (45%). Childhood worms were less prevalent. Eczema incidence was 4.68/100 person-years. Maternal hookworm was associated with reduced eczema incidence [adjusted hazard ratio (95% confidence interval), p-value: 0.71(0.51–0.99), 0.04] and modified effects of known risk factors for eczema: Dermatophagoides-specific IgE in children was positively associated with eczema incidence if the mother had no hookworm [2.72(1.11–6.63), 0.03], but not if the mother had hookworm [0.41(0.10–1.69), 0.22], interaction p-value = 0.03. Similar interactions were seen for maternal history of eczema {[2.87(1.31–6.27, 0.008) vs. [0.73(0.23–2.30), 0.60], interaction p-value = 0.05}, female gender {[1.82(1.22–2.73), 0.004 vs. [0.96(0.60–1.53), 0.87], interaction p-value = 0.04} and allergen-specific IgE. ChildhoodTrichuris trichiura and hookworm were inversely associated with eczema. Conclusions Maternal hookworm modifies effects of known risk factors for eczema. Mechanisms by which early-life worm exposures influence allergy need investigation. Worms or worm products, and intervention during pregnancy have potential for primary prevention of allergy. PMID:25171741
Xiao, Shu-hua; Xue, Jian; Shen, Bing-gui
2010-02-01
To observe the effect of mefloquine on the tegument of adult Schistosoma japonicum harbored in mice. Twelve mice were each infected with 60-80 S. japonicum cercariae. At 35 days post-infection, 10 mice were treated orally with mefloquine at a single dose of 400 mg/kg. Two mice were sacrificed at 8 h, 24 h, 3 days, 7 days, and 14 days post-treatment respectively, and schistosomes were collected by the perfusion technique, fixed and examined under a scanning electron microscope. Schistosomes obtained from the remaining 2 untreated mice served as control. 8 h post-treatment, male and female schistosomes showed focal swelling of the worm body accompanied by extensive swelling, tough junction and fusion of tegumental ridges. Meanwhile, some of the sensory structures showed enlargement and part of them collapsed. 24 h after mefloquine administration, head portion of some male and female worms revealed high swelling accompanied by severe damage to oral sucker. 3 days post-treatment, focal swelling of worm body along the whole worm was universal. In some male and female worms, the damaged tegument fused together to form a large mass protruding from the tegumental surface. In addition, focal or extensive peeling of tegumental ridges was seen or collapse of enlarged sensory structure resulted in formation of hole-like appearance. 7 days post administration, focal swelling of worm body and damage to tegument induced by mefloquine were similar to those aforementioned, but focal peeling, collapse of enlarged sensory structures, and deformation of oral sucker in male and female worms were universal. 14 days post-treatment, individual male worm survived the treatment revealed normal appearance of tegumental ridges in head portion, although light focal swelling of worm body was still observed. Mefloquine causes focal swelling of worm body, extensive and severe damage to the tegument in adult S. japonicum.
Extrusion of Contracaecum osculatum nematode larvae from the liver of cod (Gadus morhua).
Zuo, S; Barlaup, L; Mohammadkarami, A; Al-Jubury, A; Chen, D; Kania, P W; Buchmann, K
2017-10-01
Baltic cod livers have during recent years been found increasingly and heavily infected with third-stage larvae of Contracaecum osculatum. The infections are associated with an increasing population of grey seals which are final hosts for the parasite. Heavy worm burdens challenge utilization and safety of the fish liver products, and technological solutions for removal of worms are highly needed. We investigated the attachment of the worm larvae in liver tissue by use of histochemical techniques and found that the cod host encapsulates the worm larvae in layers of host cells (macrophages, fibroblasts) supported by enclosures of collagen and calcium. A series of incubation techniques, applying compounds targeting molecules in the capsule, were then tested for their effect to induce worm escape/release reactions. Full digestion solutions comprising pepsin, NaCl, HCl and water induced a fast escape of more than 60% of the worm larvae within 20 min and gave full release within 65 min but the liver tissue became highly dispersed. HCl alone, in concentrations of 48 and 72 mM, triggered a corresponding release of worm larvae with minor effect on liver integrity. A lower HCl concentration of 24 mM resulted in 80% release within 35 min. Water and physiological saline had no effect on worm release, and 1% pepsin in water elicited merely a weak escape reaction. In addition to the direct effect of acid on worm behaviour it is hypothesised that the acid effect on calcium carbonate in the encapsulation, with subsequent release of reaction products, may contribute to activation of C. osculatum larvae and induce escape reactions. Short-term pretreatment of infected cod liver and possibly other infected fish products, using low acid concentrations is suggested as part of a technological solution for worm clearance as low acid concentrations had limited macroscopic effect on liver integrity within 35 min.
Walter, Klaudia; Fulford, Anthony J C; McBeath, Rowena; Joseph, Sarah; Jones, Frances M; Kariuki, H Curtis; Mwatha, Joseph K; Kimani, Gachuhi; Kabatereine, Narcis B; Vennervald, Birgitte J; Ouma, John H; Dunne, David W
2006-10-15
In schistosomiasis endemic areas, children are very susceptible to postchemotherapy reinfection, whereas adults are relatively resistant. Different studies have reported that schistosome-specific IL-4 and IL-5 responses, or posttreatment worm-IgE levels, correlate with subsequent low reinfection. Chemotherapy kills i.v. worms providing an in vivo Ag challenge. We measured anti-worm (soluble worm Ag (SWA) and recombinant tegumental Ag (rSm22.6)) and anti-egg (soluble egg Ag) Ab levels in 177 Ugandans (aged 7-50) in a high Schistosoma mansoni transmission area, both before and 7 wk posttreatment, and analyzed these data in relation to whole blood in vitro cytokine responses at the same time points. Soluble egg Ag-Ig levels were unaffected by treatment but worm-IgG1 and -IgG4 increased, whereas worm-IgE increased in many but not all individuals. An increase in worm-IgE was mainly seen in >15-year-olds and, unlike in children, was inversely correlated to pretreatment infection intensities, suggesting this response was associated both with resistance to pretreatment infection, as well as posttreatment reinfection. The increases in SWA-IgE and rSm22.6-IgE positively correlated with pretreatment Th2 cytokines, but not IFN-gamma, induced by SWA. These relationships remained significant after allowing for the confounding effects of pretreatment infection intensity, age, and pretreatment IgE levels, indicating a link between SWA-specific Th2 cytokine responsiveness and subsequent increases in worm-IgE. An exceptionally strong relationship between IL-5 and posttreatment worm-IgE levels in < 15-year-olds suggested that the failure of younger children to respond to in vivo Ag stimulation with increased levels of IgE, is related to their lack of pretreatment SWA Th2 cytokine responsiveness.
NASA Astrophysics Data System (ADS)
Inn, Yong Woo; Sukhadia, Ashish M.
2017-05-01
In the extrusion blow molding process of high density polyethylene (HDPE) for making of large size drums, string-like defects, which are referred to as worm melt fracture in the industry, are often observed on the extrudate surface. Such string-like defects in various shapes and sizes are observed in capillary extrusion at very high shear rates after the slip-stick transition. The HDPE resin with broader molecular weight distribution (MWD) exhibits a greater degree of worm melt fracture while the narrow MWD PE resin, which has higher slip velocity and a uniform slip layer, shows a lesser degree of worm melt fracture. It is hypothesized that the worm melt fracture is related to fast die build-up and cohesive slip layer, a failure within the polymer melts at an internal surface. If the cohesive slip layer at an internal surface emerges out from the die, it can be attached on the surface of extrudate as string-like defects, the worm melt fracture. The resin having more small chains and lower plateau modulus can be easier to have such an internal failure and consequently exhibit more "worm" defects.
Propagation Modeling and Defending of a Mobile Sensor Worm in Wireless Sensor and Actuator Networks
Wang, Tian; Wu, Qun; Wen, Sheng; Cai, Yiqiao; Tian, Hui; Chen, Yonghong; Wang, Baowei
2017-01-01
WSANs (Wireless Sensor and Actuator Networks) are derived from traditional wireless sensor networks by introducing mobile actuator elements. Previous studies indicated that mobile actuators can improve network performance in terms of data collection, energy supplementation, etc. However, according to our experimental simulations, the actuator’s mobility also causes the sensor worm to spread faster if an attacker launches worm attacks on an actuator and compromises it successfully. Traditional worm propagation models and defense strategies did not consider the diffusion with a mobile worm carrier. To address this new problem, we first propose a microscopic mathematical model to describe the propagation dynamics of the sensor worm. Then, a two-step local defending strategy (LDS) with a mobile patcher (a mobile element which can distribute patches) is designed to recover the network. In LDS, all recovering operations are only taken in a restricted region to minimize the cost. Extensive experimental results demonstrate that our model estimations are rather accurate and consistent with the actual spreading scenario of the mobile sensor worm. Moreover, on average, the LDS outperforms other algorithms by approximately 50% in terms of the cost. PMID:28098748
Paris-Palacios, Séverine; Mosleh, Yahia Y; Almohamad, Mohamad; Delahaut, Laurence; Conrad, Arnaud; Arnoult, Fabrice; Biagianti-Risbourg, Sylvie
2010-06-01
Tubifex is the only animal reported to respond with autotomy to contamination. This response of contaminated worm is understood as a mode of metal excretion. Few data concern the potential of organic compounds to induce tubifex autotomy. The objective of this study was to investigate if autotomy can be induced by a herbicide isoproturon (IP) and be related to the way of excretion. Isoproturon accumulation in worm tissues and its effect on tubifex mortality, autotomy and regeneration rates were analysed after 4 and 7 days of exposure to the herbicide and also when worms were replaced for 10 days in clean water. IP accumulated in the same way in all parts of the worm body but IP metabolite rates were significantly higher in the posterior part of the worm. Thus the loss of the posterior part allows the worm to eliminate an important amount of pesticide. Autotomy has a population importance and is related to the degree of worm contamination so it may become an interesting biomarker. Copyright (c) 2010 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Mo, Changyeun; Kim, Giyoung; Kim, Moon S.; Lim, Jongguk; Lee, Seung Hyun; Lee, Hong-Seok; Cho, Byoung-Kwan
2017-09-01
The rapid detection of biological contaminants such as worms in fresh-cut vegetables is necessary to improve the efficiency of visual inspections carried out by workers. Multispectral imaging algorithms were developed using visible-near-infrared (VNIR) and near-infrared (NIR) hyperspectral imaging (HSI) techniques to detect worms in fresh-cut lettuce. The optimal wavebands that can detect worms in fresh-cut lettuce were investigated for each type of HSI using one-way ANOVA. Worm-detection imaging algorithms for VNIR and NIR imaging exhibited prediction accuracies of 97.00% (RI547/945) and 100.0% (RI1064/1176, SI1064-1176, RSI-I(1064-1173)/1064, and RSI-II(1064-1176)/(1064+1176)), respectively. The two HSI techniques revealed that spectral images with a pixel size of 1 × 1 mm or 2 × 2 mm had the best classification accuracy for worms. The results demonstrate that hyperspectral reflectance imaging techniques have the potential to detect worms in fresh-cut lettuce. Future research relating to this work will focus on a real-time sorting system for lettuce that can simultaneously detect various defects such as browning, worms, and slugs.
Modeling the influence of leaf demography on remotely sensed data using DART and PROSPECT-D
NASA Astrophysics Data System (ADS)
Feret, J. B.; Grau, E.; Barbier, N.; Berveiller, D.; Chave, J.; Durrieu, S.; Gastellu-Etchegorry, J. P.; Hmimina, G.; Lefèvre-Fonollosa, M. J.; Proisy, C.; Soudani, K.; Vincent, G.
2016-12-01
The seasonality of Amazon forest productivity and photosynthetic activity has recently been investigated under a new perspective by a series of publications. The debate about possible factors explaining this seasonality is vivid, and the possibility of several hypotheses has been tested, including canopy phenology and leaf demography, and changes in illumination geometry combined with the complex 3D structure of the canopy. A manifold of measurements and techniques have been used to test these hypotheses, including field observations of leaf demography from ground measured litterfall and phenocam, airborne and satellite remote sensing and 3 dimensional radiative transfer modeling. Our study explores the relative influence of leaf demography and illumination geometry on remotely sensed data. To achieve this, we take advantage of the latest advances in the domain of physical modeling at both leaf and canopy scale. The leaf optical properties model PROSPECT-D was used to model leaf optical properties at various growth stages based on field observations and theoretical leaf biochemical composition during its development and senescence. The 3-dimensional radiative transfer model DART was used to simulate various levels of complexity of canopy covers, from a turbid layer to complex canopy derived from airborne LiDAR acquisitions. Data for leaf demography and ontogeny taken from recent publications was used and integrated into canopy simulations corresponding to year-long observations. Data acquisitions were performed in the frame of the HyperTropik project, funded by CNES, Our results focus on analyzing the influence of separated and combined factors such as illumination geometry, leaf biochemistry and leaf demography on various spectral attributes, including Enhanced vegetation index and hyperspectral metrics.
Lifted worm algorithm for the Ising model
NASA Astrophysics Data System (ADS)
Elçi, Eren Metin; Grimm, Jens; Ding, Lijie; Nasrawi, Abrahim; Garoni, Timothy M.; Deng, Youjin
2018-04-01
We design an irreversible worm algorithm for the zero-field ferromagnetic Ising model by using the lifting technique. We study the dynamic critical behavior of an energylike observable on both the complete graph and toroidal grids, and compare our findings with reversible algorithms such as the Prokof'ev-Svistunov worm algorithm. Our results show that the lifted worm algorithm improves the dynamic exponent of the energylike observable on the complete graph and leads to a significant constant improvement on toroidal grids.
Surface characterization and adhesion and friction properties of hydrophobic leaf surfaces.
Burton, Zachary; Bhushan, Bharat
2006-01-01
Super-hydrophobic surfaces as well as low adhesion and friction are desirable for various industrial applications. Certain plant leaves are known to be hydrophobic in nature. These leaves are hydrophobic due to the presence of microbumps and a thin wax film on the surface of the leaf. The purpose of this study is to fully characterize the leaf surface and to separate out the effects of the microbumps and the wax on the hydrophobicity. Furthermore, the adhesion and friction properties of the leaves, with and without wax, are studied. Using an optical profiler and an atomic/friction force microscope (AFM/FFM), measurements on the hydrophobic leaves, both with and without wax, were made to fully characterize the leaf surface. Using a model that predicts contact angle as a function of roughness, the roughness factor for the hydrophobic leaves has been calculated, which is used to calculate the contact angle for a flat leaf surface. It is shown that both the microbumps and the wax play an equally important role in the hydrophobic nature as well as adhesion and friction of the leaf. This study will be useful in developing super-hydrophobic surfaces.
Nyaka Ngobisa, A. I. C.; Zainal Abidin, M. A.; Wong, M. Y.; Wan Noordin, M. W. D.
2013-01-01
Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations – Selangor, Perak, and Johor states – in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis. PMID:25288924
Nyaka Ngobisa, A I C; Zainal Abidin, M A; Wong, M Y; Wan Noordin, M W D
2013-03-01
Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations - Selangor, Perak, and Johor states - in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis.
Inducible repression of multiple expansin genes leads to growth suppression during leaf development.
Goh, Hoe-Han; Sloan, Jennifer; Dorca-Fornell, Carmen; Fleming, Andrew
2012-08-01
Expansins are cell wall proteins implicated in the control of plant growth via loosening of the extracellular matrix. They are encoded by a large gene family, and data linked to loss of single gene function to support a role of expansins in leaf growth remain limited. Here, we provide a quantitative growth analysis of transgenics containing an inducible artificial microRNA construct designed to down-regulate the expression of a number of expansin genes that an expression analysis indicated are expressed during the development of Arabidopsis (Arabidopsis thaliana) leaf 6. The results support the hypothesis that expansins are required for leaf growth and show that decreased expansin gene expression leads to a more marked repression of growth during the later stage of leaf development. In addition, a histological analysis of leaves in which expansin gene expression was suppressed indicates that, despite smaller leaves, mean cell size was increased. These data provide functional evidence for a role of expansins in leaf growth, indicate the importance of tissue/organ developmental context for the outcome of altered expansin gene expression, and highlight the separation of the outcome of expansin gene expression at the cellular and organ levels.
Dues, Dylan J; Schaar, Claire E; Johnson, Benjamin K; Bowman, Megan J; Winn, Mary E; Senchuk, Megan M; Van Raamsdonk, Jeremy M
2017-07-01
Mutations affecting components of the mitochondrial electron transport chain have been shown to increase lifespan in multiple species including the worm Caenorhabditis elegans. While it was originally proposed that decreased generation of reactive oxygen species (ROS) resulting from lower rates of electron transport could account for the observed increase in lifespan, recent evidence indicates that ROS levels are increased in at least some of these long-lived mitochondrial mutants. Here, we show that the long-lived mitochondrial mutant isp-1 worms have increased resistance to oxidative stress. Our results suggest that elevated ROS levels in isp-1 worms cause the activation of multiple stress-response pathways including the mitochondrial unfolded protein response, the SKN-1-mediated stress response, and the hypoxia response. In addition, these worms have increased expression of specific antioxidant enzymes, including a marked upregulation of the inducible superoxide dismutase genes sod-3 and sod-5. Examining the contribution of sod-3 and sod-5 to the oxidative stress resistance in isp-1 worms revealed that loss of either of these genes increased resistance to oxidative stress, but not other forms of stress. Deletion of sod-3 or sod-5 decreased the lifespan of isp-1 worms and further exacerbated their slow physiologic rates. Thus, while deletion of sod-3 and sod-5 genes has little impact on stress resistance, physiologic rates or lifespan in wild-type worms, these genes are required for the longevity of isp-1 worms. Overall, this work shows that the increased resistance to oxidative stress in isp-1 worms does not account for their longevity, and that resistance to oxidative stress can be experimentally dissociated from lifespan. Copyright © 2017 Elsevier Inc. All rights reserved.
American Beech Leaf-litter Leachate Chemistry: Effects of Geography and Phenophase
NASA Astrophysics Data System (ADS)
Hudson, J. E.; Levia, D. F., Jr.; Wheeler, K. I.; Winters, C. G.; Vaughan, M.; Chace, J.; Sleeper, R.
2017-12-01
The decomposition of leaves from broadleaved trees contributes to the energy budget of forested watersheds via dissolved organic matter, nutrients, and biological activity. Although it is often implicitly assumed that intraspecific differences in leaf-litter leachate chemistry do not significantly differ geographically, we attempted to discern how these inputs may vary from single tree species that is known to have two genetically distinct and geographically separate populations, as well as how these inputs may change throughout autumn senescence and after abscission. We analyzed the physical and chemical leaf traits and leaf leachates of leaves from Fagus grandifolia (American beech; n = 360) during three phenophases: fresh green, senescing, and fallen. During each phenophase, leaves were collected from four sites along a geographic transect stretching from Vermont to North Carolina (over 1400 km), with two sites representing each genetic population and differing climatic conditions. Pooled leaf leachates from each site and phenophase were analyzed for routine solutes and nutrients, as well as fluorescent and UV-visible absorbance indices. Quantities of macro- and micronutrients were highly variable among sites and phenophases but tended to be lowest from fallen leaves, while measured fluorescence and absorbance indices tended to increase during leaves collected during senescence. Results suggest significant differences in leached nutrients among field sites, while optical properties and nutrients varied significantly among phenophases. Aromaticity and molecular weight of DOM in leachates was generally low, and aromaticity and humification of leachates both increased as leaves aged throughout the selected phenophases. Results also suggest that geographically (or genetically) separate populations of the same species do not experience senescence in the same way and that implicit assumptions of intraspecific uniformity of leaf-litter leachate chemistry for a given tree species may be invalid. Funding note: Research made possible by the U.S. National Science Foundation (Grant No. IIA-1330238, IIA-1330446, and IIA-1330406).
NASA Astrophysics Data System (ADS)
Zapater, M.; Breda, N.; Storchi, G.; Granier, A.
2005-12-01
Intra and interspecific variability in leaf gas exchange (net assimilation, stomatal conductance, transpiration, water use efficiency: WUE), in carbon isotope composition (d13C) and leaf characteristics related to photosynthesis was assessed in 5 trees species growing in a young broad-leaved mixed forest in North-Eastern France (Hesse, Lorraine). The studied species belong to contrasted functional groups of light tolerance: European beech (Fagus sylvatica) as shade tolerant species; sessile oak (Quercus petraea) and hornbeam (Carpinus betulus) as semitolerant species; silver birch (Betula pendula) and European aspen (Populus tremula) as shade intolerant species (pioneer species). Gas exchange was measured at leaf level in the upper and the lower canopy layers using a portable system (LI-6200, Licor). d13C signatures were determined in the sun and shade leaves in both bulk material and soluble sugars. Clear differences in bulk leaves and soluble sugars d13C and intrinsic WUEint were found among the investigated species, whatever the leaf location in the canopy. Within each tree species, shade leaves exhibited lower WUEint and more negative d13C than sun leaves. Little variability among trees was found for a given species. The 3 functional groups were separated by their leaf carbon content. Nevertheless each of the variables d13C, leaf mass area and nitrogen content, alone, could not separate the groups. A linear relationship was found between WUEint and d13C at the intraspecific level (r2 = 0.87 for leaves; r2 =0.89 for sugars) and at the interspecific level (r2 = 0.72 for bulk leaves). Nevertheless, this relationship differed from that of Farquhar et al. (1982), due to a different intercept, while the slope was the same. The causes of these variations are discussed. Key words: d13C; deciduous; mixed forest; WUEint; shade tolerance.
USDA-ARS?s Scientific Manuscript database
Lumbricus terrestris L. (the dew worm) forages, mates and migrates on the soil surface during the night. Its distribution covers a broad latitudinal gradient and variation in day length conditions. Since soil-surface activity is crucial for the survival and reproduction of dew worms, it is conceivab...
Effect of time on migration of Oesophagostomum spp. and Hyostrongylus rubidus out of agar-gel.
Nosal, P; Christensen, C M; Nansen, P
1998-01-01
The agar-gel migration technique has previously been described, however, aspects regarding the effect of timing on worm migration needed further scrutiny. In the first experiment, pigs inoculated with Oesophagostomum dentatum were slaughtered simultaneously and their intestines stored at 21-23 degrees C until processed pairwise 2, 4, 6, 8, 12 and 18 h after slaughter. More than 95% of the worms migrated out of the agar if processed within 6 h. In the second experiment, intestines were treated immediately after slaughter and the migratory speed of adult worms or 4th-stage larvae of O. dentatum or O. quadrispinulatum, or adult Hyostrongylus rubidus were studied. For both Oesophagostomum species, more than 90% of the worms were recovered within 1 h. H. rubidus was significantly slower; however, approximately 98% of the worms had migrated out of the agar-gel by 20 h. This information is essential in planning experiments where recovery of live worms is of value.
Hairworm anti-predator strategy: a study of causes and consequences.
Ponton, F; Lebarbenchon, C; Lefèvre, T; Thomas, F; Duneau, D; Marché, L; Renault, L; Hughes, D P; Biron, D G
2006-11-01
One of the most fascinating anti-predator responses displayed by parasites is that of hairworms (Nematomorpha). Following the ingestion of the insect host by fish or frogs, the parasitic worm is able to actively exit both its host and the gut of the predator. Using as a model the hairworm, Paragordius tricuspidatus, (parasitizing the cricket Nemobius sylvestris) and the fish predator Micropterus salmoïdes, we explored, with proteomics tools, the physiological basis of this anti-predator response. By examining the proteome of the parasitic worm, we detected a differential expression of 27 protein spots in those worms able to escape the predator. Peptide Mass Fingerprints of candidate protein spots suggest the existence of an intense muscular activity in escaping worms, which functions in parallel with their distinctive biology. In a second step, we attempted to determine whether the energy expended by worms to escape the predator is traded off against its reproductive potential. Remarkably, the number of offspring produced by worms having escaped a predator was not reduced compared with controls.
Zain, Mariani Mohd; Yahaya, Zary Shariman; Him, Nik Ahmad Irwan Izzauddin Nik
2016-11-01
To date, the ivermectin resistance in nematode parasites has been reported and many studies are carried out to determine the causes of this problem. A free-living Caenorhabditis elegans is used as a model system for this study to investigate the response of C. elegans to ivermectin exposure by using larval development assay. Worms were exposed to ivermectin at concentration from 1 ng/mL to 10 ng/mL and dimethyl sulphoxide (DMSO) as a control. The developments of the worms were monitored for 24, 48, 72, and 96 hours until the worms become adults. Results indicated that worms' growth began to be affected by ivermectin at a concentration of 5 ng/mL, while at the concentration of 6, 7, 8, 9, and 10 ng/mL, the growth of worms were inhibited compared to control worms. Further study of the protein expression in C. elegans should be done to investigate the up-regulated and down-regulated proteins involve in ivermectin resistance.
WormQTL—public archive and analysis web portal for natural variation data in Caenorhabditis spp
Snoek, L. Basten; Van der Velde, K. Joeri; Arends, Danny; Li, Yang; Beyer, Antje; Elvin, Mark; Fisher, Jasmin; Hajnal, Alex; Hengartner, Michael O.; Poulin, Gino B.; Rodriguez, Miriam; Schmid, Tobias; Schrimpf, Sabine; Xue, Feng; Jansen, Ritsert C.; Kammenga, Jan E.; Swertz, Morris A.
2013-01-01
Here, we present WormQTL (http://www.wormqtl.org), an easily accessible database enabling search, comparative analysis and meta-analysis of all data on variation in Caenorhabditis spp. Over the past decade, Caenorhabditis elegans has become instrumental for molecular quantitative genetics and the systems biology of natural variation. These efforts have resulted in a valuable amount of phenotypic, high-throughput molecular and genotypic data across different developmental worm stages and environments in hundreds of C. elegans strains. WormQTL provides a workbench of analysis tools for genotype–phenotype linkage and association mapping based on but not limited to R/qtl (http://www.rqtl.org). All data can be uploaded and downloaded using simple delimited text or Excel formats and are accessible via a public web user interface for biologists and R statistic and web service interfaces for bioinformaticians, based on open source MOLGENIS and xQTL workbench software. WormQTL welcomes data submissions from other worm researchers. PMID:23180786
WormQTL--public archive and analysis web portal for natural variation data in Caenorhabditis spp.
Snoek, L Basten; Van der Velde, K Joeri; Arends, Danny; Li, Yang; Beyer, Antje; Elvin, Mark; Fisher, Jasmin; Hajnal, Alex; Hengartner, Michael O; Poulin, Gino B; Rodriguez, Miriam; Schmid, Tobias; Schrimpf, Sabine; Xue, Feng; Jansen, Ritsert C; Kammenga, Jan E; Swertz, Morris A
2013-01-01
Here, we present WormQTL (http://www.wormqtl.org), an easily accessible database enabling search, comparative analysis and meta-analysis of all data on variation in Caenorhabditis spp. Over the past decade, Caenorhabditis elegans has become instrumental for molecular quantitative genetics and the systems biology of natural variation. These efforts have resulted in a valuable amount of phenotypic, high-throughput molecular and genotypic data across different developmental worm stages and environments in hundreds of C. elegans strains. WormQTL provides a workbench of analysis tools for genotype-phenotype linkage and association mapping based on but not limited to R/qtl (http://www.rqtl.org). All data can be uploaded and downloaded using simple delimited text or Excel formats and are accessible via a public web user interface for biologists and R statistic and web service interfaces for bioinformaticians, based on open source MOLGENIS and xQTL workbench software. WormQTL welcomes data submissions from other worm researchers.
Persistence of the efficacy of copper oxide wire particles against Haemonchus contortus in sheep.
Galindo-Barboza, A J; Torres-Acosta, J F J; Cámara-Sarmiento, R; Sandoval-Castro, C A; Aguilar-Caballero, A J; Ojeda-Robertos, N F; Reyes-Ramírez, R; España-España, E
2011-03-10
The aim was to determine the persistent efficacy of copper oxide wire particles (COWP) against Haemonchus contortus in sheep, using the harmonization guidelines protocol. Thirty-six male lambs (2 months old) reared free of gastrointestinal nematodes were used (average body weight of 10.8±3.8kg). Before and for the duration of the study, lambs were kept in raised cages with slatted floors and were offered ad libitum a complete mixed diet. Animals were divided into six groups (n=6): one non-treated control group (G0) and five groups treated with one COWP capsule (1.7g of copper oxide; Copinox(®)). Animals in each group were treated on pre-defined dates before the artificial infection was applied: days -35 (G1), -28 (G2), -21 (G3), -14 (G4) and -7 (G5). On day 0 animals were infected with 3700 H. contortus infective larvae per animal. Animals were humanely slaughtered between days 22 and 23 post-infection. The abomasums were individually washed to obtain the contents. These organs were subjected to separate artificial digestions. Adult parasites were counted from the abomasum contents and the larvae from the digested material. Worm burden geometric means were calculated for each group. A significant worm burden reduction in either of the treated groups (G1, G2, G3, G4, and G5) compared to the control (G0) was considered as persistence of the anthelmintic effect. Copper levels were determined from individual liver samples of each animal. The geometric mean worm burden of the control group (G0) was 1959. Compared to the control, worm burdens geometric means were significantly reduced in groups G1 (1108), G4 (528) and G5 (1063) (P<0.03). Efficacies in G1, G4 and G5 were 43.4%, 73.0% and 45.7% respectively. No significant reduction was found for G2 (1342) and G3 (1430). A larger quantity of Cu was found in the livers of treated animals compared to the control group (P<0.05) except for G3 (P=0.06). A negative association between Cu liver content and worm burdens was found (r=-0.42, P<0.05). Live weight gain was similar in all groups and no clinical or post-mortem manifestations of Cu toxicity were recorded in treated animals. Copyright © 2010 Elsevier B.V. All rights reserved.
Kulkarni, Paresh; Paul, Rajkumar; Ganesh, N
2010-07-01
Persea americana is much sought after both for the nutritional value of its fruit and the medicinal values of its various plant parts. A chromosomal aberration assay was undertaken to evaluate the potential genotoxicity of crude extracts from avocado fruits and leaves. Chromosomal aberrations were observed in cultured human peripheral lymphocytes exposed to separately increasing concentrations of 50% methanolic extracts of Persea americana fruit and leaves. The groups exposed to leaf and fruit extracts, respectively, showed a concentration-dependent increase in chromosomal aberrations as compared to that in a control group. The mean percentage total aberrant metaphases at 100 mg/kg, 200 mg/kg, and 300 mg/kg concentrations of leaf extract were found respectively to be 58 ± 7.05, 72 ± 6.41, and 78 ± 5.98, which were significantly higher (p < 0.0001 each) than that in the control group (6 ± 3.39). The mean percentage total aberrant metaphases at 100 mg/kg, 200 mg/kg, and 300 mg/kg concentrations of fruit extract were found to be 18 ± 5.49, 40 ± 10.00, and 52 ± 10.20, respectively, which were significantly higher (p = 0.033, p < 0.0001, and p < 0.0001, respectively) than that for control (6 ± 3.39). Acrocentric associations and premature centromeric separation were the two most common abnormalities observed in both the exposed groups. The group exposed to leaf extracts also showed a significant number of a variety of other structural aberrations, including breaks, fragments, dicentrics, terminal deletion, minutes, and Robertsonian translocations. The group exposed to leaf extract showed higher frequency of all types of aberrations at equal concentrations as compared to the group exposed to fruit extract.
Effect of greenhouse conditions on the leaf apoplastic proteome of Coffea arabica plants.
Guerra-Guimarães, Leonor; Vieira, Ana; Chaves, Inês; Pinheiro, Carla; Queiroz, Vagner; Renaut, Jenny; Ricardo, Cândido P
2014-06-02
This work describes the coffee leaf apoplastic proteome and its modulation by the greenhouse conditions. The apoplastic fluid (APF) was obtained by leaf vacuum infiltration, and the recovered proteins were separated by 2-DE and subsequently identified by matrix assisted laser desorption/ionization time of flight-mass spectrometry, followed by homology search in EST coffee databases. Prediction tools revealed that the majority of the 195 identified proteins are involved in cell wall metabolism and in stress/defense responses. Although most of the proteins follow the classical secretory mechanism, a low percentage of them seem to result from unconventional secretion (leaderless secreted proteins). Principal components analysis revealed that the APF samples formed two distinct groups, with the temperature amplitude mostly contributing for this separation (higher or lower than 10°C, respectively). Sixty one polypeptide spots allowed defining these two groups and 28 proteins were identified, belonging to carbohydrate metabolism, cell wall modification and proteolysis. Interestingly stress/defense proteins appeared as more abundant in Group I which is associated with a higher temperature amplitude. It seems that the proteins in the coffee leaf APF might be implicated in structural modifications in the extracellular space that are crucial for plant development/adaptation to the conditions of the prevailing environment. This is the first detailed proteomic study of the coffee leaf apoplastic fluid (APF) and of its modulation by the greenhouse conditions. The comprehensive overview of the most abundant proteins present in the extra-cellular compartment is particularly important for the understanding of coffee responses to abiotic/biotic stress. This article is part of a Special Issue entitled: Environmental and structural proteomics. Copyright © 2014 Elsevier B.V. All rights reserved.
Miller, H R
1980-01-01
Several of the parameters related to the efficacy of passive protection against Nippostrongylus brasiliensis were studied in female hybrid (PVG/c x DA)F1 and outbred Wistar rats. The time after infection at which immune serum was given did, to some extent, alter the degree of protection conferred. There was substantial protection 8 days after challenge in rats given hyperimmune serum (HIS) either as daily injections 4-7 days post-infection or as a single dose on day 4. Eight separate experiments in which HIS was injected 4 days after challenge with 1000 l3 resulted in expulsion of 96 +/- 2% of the worm burdens by day 8. In a further six experiments, following infection with 2000 l3 and using the same protocol, 85 +/- 3% of the worm burden was expelled by day 8. A lag of 2 days between serum transfer and commencement of worm expulsion was consistently observed and, within the space of a further 2-4 days, more than 95% of the parasites were expelled. Transplanted 'normal' and 'damaged' adult worms were also susceptible to the passive transfer of HIS. Sera recovered from rats immunized with two or three challenges (hyperimmune sera) were more protective than sera from rats given one challenge. Serum from rats challenged for the first time 6 days previously conferred significant protection against a 1000 l3 infection and sera recovered 8 and 10-12 days post-infection with 4000 l3 protected recipients with increasing effectiveness. Thoracic duct lymph collected on the tenth day of infection with 4000 l3 was also protective. The response to both primary infection and hyperimmune serum was dose-dependent. The consistently good protection achieved in the present study when compared with the variable success of previous experiments (reviewed by Ogilvie & Jones, 1971) may be a function of the strain and sex of the rats used, together with modifications of the immunization protocols. The relevance of these findings to mucosal defences against N. brasiliensis is discussed. PMID:7429533
Yang, Wei; Wang, Dong-sheng; Liu, Man-qiang; Hu, Feng; Li, Hui-xin; Huang, Zhong-yang; Chang, Yi-jun; Jiao, Jia-guo
2015-10-01
In this experiment, different proportions of the cattle manure, tea-leaf, herb and mushroom residues, were used as food for earthworm (Eisenia fetida) to study the growth of the earth-worm. Then the characteristics and transformation of nutrient content and three-dimensional excitation emission matrix fluorescence (3DEEM) of dissolved organic matter (DOM) during vermistabilization were investigated by means of chemical and spectroscopic methods. The result showed that the mixture of different ratios of cattle manure with herb residue, and cattle manure with tea-leaf were conducive to the growth of earthworm, while the materials compounded with mushroom residue inhibited the growth of earthworm. With the increasing time of verimcomposting, the pH in vermicompost tended to be circumneutral and weakly acidic, and there were increases in electrical conductivity, and the contents of total nitrogen, total phosphorus, available nitrogen, and available phosphorus, while the total potassium and available potassium increased first and then decreased, and the organic matter content decreased. 3DEEM and fluorescence regional integration results indicated that, the fluorescence of protein-like fluorescence peaks declined significantly, while the intensity of humic-like fluorescence peak increased significantly in DOM. Vermicomposting process might change the compositions of DOM with elevated concentrations of humic acid and fulvic acid in the organics. In all, this study suggested the suitability of 3DEEM for monitoring the organics transformation and assessing the maturity in the vermicomposting.
Fazal, Farhan; Mane, Prajwal P; Rai, Manoj P; Thilakchand, Karadka R; Bhat, Harshith P; Kamble, Prathibha S; Palatty, Princy L; Baliga, Manjeshwar Shrinath
2014-08-26
Since antiquity, Piper betel. Linn, commonly known as betel vine, has been used as a religious, recreational and medicinal plant in Southeast Asia. The leaves, which are the most commonly used plant part, are pungent with aromatic flavor and are widely consumed as a mouth freshener. It is carminative, stimulant, astringent and is effective against parasitic worms. Experimental studies have shown that it possess diverse biological and pharmacological effects, which includes antibacterial, antifungal, larvicidal, antiprotozal, anticaries, gastroprotective effects, free radical scavenging, antioxidant, anti-inflammatory hepatoprotective, immunomodulatory, antiulcer and chemopreventive activities. The active principles hydroxychavicol, allylpyrocatechol and eugenol with their plethora of pharmacological properties may also have the potential to develop as bioactive lead molecule. In this review, an attempt is made to summarize the religious, traditional uses, phytochemical composition and experimentally validated pharmacological properties of Piper betel. Emphasis is also placed on aspects warranting detail studies for it to be of pharmaceutical/clinical use to humans.
From Flowers to Worms: Understanding Nature's Cycle.
ERIC Educational Resources Information Center
Texas Child Care, 1995
1995-01-01
Gardening helps children learn how plants sprout, grow, bloom, and then wither away, leaving seeds behind. Participating in this natural process allows children to experience the stages of life. Suggested gardening activities include studying dandelions, focusing on culture for garden plant selection, and constructing a worm box or worm terrarium…
Code of Federal Regulations, 2014 CFR
2014-01-01
...) Well formed. (2) Free From: (i) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv...) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv) Freezing injury; (v) Internal...) Carefully packed; (v) Fairly clean; and, (vi) Not badly misshapen. (2) Free From: (i) Worm holes; (ii...
Code of Federal Regulations, 2013 CFR
2013-01-01
...) Well formed. (2) Free From: (i) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv...) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv) Freezing injury; (v) Internal...) Carefully packed; (v) Fairly clean; and, (vi) Not badly misshapen. (2) Free From: (i) Worm holes; (ii...
Local structure of numerically generated worm hole spacetime.
NASA Astrophysics Data System (ADS)
Siino, M.
The author investigates the evolution of the apparent horizons in a numerically gererated worm hole spacetime. The behavior of the apparent horizons is affected by the dynamics of the matter field. By using the local mass of the system, he interprets the evolution of the worm hole structure.
Code of Federal Regulations, 2011 CFR
2011-01-01
...: (i) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv) Freezing injury; (v...) Carefully packed; (v) Clean; and, (vi) Fairly well formed. (2) Free From: (i) Worm holes; (ii) Broken skins..., (vi) Not badly misshapen. (2) Free From: (i) Worm holes; (ii) Broken skins which are not healed; (iii...
Code of Federal Regulations, 2012 CFR
2012-01-01
...: (i) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv) Freezing injury; (v...) Carefully packed; (v) Clean; and, (vi) Fairly well formed. (2) Free From: (i) Worm holes; (ii) Broken skins..., (vi) Not badly misshapen. (2) Free From: (i) Worm holes; (ii) Broken skins which are not healed; (iii...
Code of Federal Regulations, 2010 CFR
2010-01-01
...: (i) Worm holes; (ii) Broken skins which are not healed; (iii) Sunscald; (iv) Freezing injury; (v...) Carefully packed; (v) Clean; and, (vi) Fairly well formed. (2) Free From: (i) Worm holes; (ii) Broken skins..., (vi) Not badly misshapen. (2) Free From: (i) Worm holes; (ii) Broken skins which are not healed; (iii...
USDA-ARS?s Scientific Manuscript database
Nondestructive methods based on fluorescence hyperspectral imaging (HSI) techniques were developed in order to detect worms on fresh-cut lettuce. The optimal wavebands for detecting worms on fresh-cut lettuce were investigated using the one-way ANOVA analysis and correlation analysis. The worm detec...
Ogamdi, S O; Onwe, F
2001-01-01
The incidence and the prevalence of Guinea worm disease, a major cause of disability and a frequent cause of serious permanent deformity, were both drastically reduced in Ohaukwu Local Government Communities, with the provision (through bore holes) of a safer form of drinking water. Since 1986, the Carter Center program has been working to eradicate Guinea worm. The bore holes were dug through the Wasatan Project, a Japanese-funded grant awarded to the Enugu State Ministry of Health to help provide safer drinking water in the local communities. Bore holes were dug in several communities in Ohaukwu Local Government Areas between January 1991 and June 1991. The number of Guinea worm cases in the selected communities was ascertained and recorded by health workers. There was more than a 90% reduction in the number of Guinea worm (Dracunculus medinensis) cases after one year. Data collection began in June 1991, shortly after the completion of bore holes in the selected communities. By December 1998, when one of the villages was spot checked for Guinea worm infection, no active case was found. There is a need for post evaluation of all the villages studied to determine the current prevalence of Guinea worm disease.
Microfluidic Devices in Advanced Caenorhabditis elegans Research.
Muthaiyan Shanmugam, Muniesh; Subhra Santra, Tuhin
2016-08-02
The study of model organisms is very important in view of their potential for application to human therapeutic uses. One such model organism is the nematode worm, Caenorhabditis elegans. As a nematode, C. elegans have ~65% similarity with human disease genes and, therefore, studies on C. elegans can be translated to human, as well as, C. elegans can be used in the study of different types of parasitic worms that infect other living organisms. In the past decade, many efforts have been undertaken to establish interdisciplinary research collaborations between biologists, physicists and engineers in order to develop microfluidic devices to study the biology of C. elegans. Microfluidic devices with the power to manipulate and detect bio-samples, regents or biomolecules in micro-scale environments can well fulfill the requirement to handle worms under proper laboratory conditions, thereby significantly increasing research productivity and knowledge. The recent development of different kinds of microfluidic devices with ultra-high throughput platforms has enabled researchers to carry out worm population studies. Microfluidic devices primarily comprises of chambers, channels and valves, wherein worms can be cultured, immobilized, imaged, etc. Microfluidic devices have been adapted to study various worm behaviors, including that deepen our understanding of neuromuscular connectivity and functions. This review will provide a clear account of the vital involvement of microfluidic devices in worm biology.
Durability Characteristics Analysis of Plastic Worm Wheel with Glass Fiber Reinforced Polyamide.
Kim, Gun-Hee; Lee, Jeong-Won; Seo, Tae-Il
2013-05-10
Plastic worm wheel is widely used in the vehicle manufacturing field because it is favorable for weight lightening, vibration and noise reduction, as well as corrosion resistance. However, it is very difficult for general plastics to secure the mechanical properties that are required for vehicle gears. If the plastic resin is reinforced by glass fiber in the fabrication process of plastic worm wheel, it is possible to achieve the mechanical properties of metallic material levels. In this study, the mechanical characteristic analysis of the glass-reinforced plastic worm wheel, according to the contents of glass fiber, is performed by analytic and experimental methods. In the case of the glass fiber-reinforced resin, the orientation and contents of glass fibers can influence the mechanical properties. For the characteristic prediction of plastic worm wheel, computer-aided engineering (CAE) analysis processes such as structural and injection molding analysis were executed with the polyamide resin reinforcement glass fiber (25 wt %, 50 wt %). The injection mold for fabricating the prototype plastic worm wheel was designed and made to reflect the CAE analysis results. Finally, the durability of prototype plastic worm wheel fabricated by the injection molding process was evaluated by the experimental method and the characteristics according to the glass fiber contents.
Durability Characteristics Analysis of Plastic Worm Wheel with Glass Fiber Reinforced Polyamide
Kim, Gun-Hee; Lee, Jeong-Won; Seo, Tae-Il
2013-01-01
Plastic worm wheel is widely used in the vehicle manufacturing field because it is favorable for weight lightening, vibration and noise reduction, as well as corrosion resistance. However, it is very difficult for general plastics to secure the mechanical properties that are required for vehicle gears. If the plastic resin is reinforced by glass fiber in the fabrication process of plastic worm wheel, it is possible to achieve the mechanical properties of metallic material levels. In this study, the mechanical characteristic analysis of the glass-reinforced plastic worm wheel, according to the contents of glass fiber, is performed by analytic and experimental methods. In the case of the glass fiber-reinforced resin, the orientation and contents of glass fibers can influence the mechanical properties. For the characteristic prediction of plastic worm wheel, computer-aided engineering (CAE) analysis processes such as structural and injection molding analysis were executed with the polyamide resin reinforcement glass fiber (25 wt %, 50 wt %). The injection mold for fabricating the prototype plastic worm wheel was designed and made to reflect the CAE analysis results. Finally, the durability of prototype plastic worm wheel fabricated by the injection molding process was evaluated by the experimental method and the characteristics according to the glass fiber contents. PMID:28809248
Lamberton, Poppy H L; Faust, Christina L; Webster, Joanne P
2017-06-16
Mass drug administration of praziquantel is the World Health Organization's endorsed control strategy for schistosomiasis. A decade of annual treatments across sub-Saharan Africa has resulted in significant reductions of infection prevalence and intensity levels, although 'hotspots' remain. Repeated drug treatments place strong selective pressures on parasites, which may affect life-history traits that impact transmission dynamics. Understanding drug treatment responses and the evolution of such traits can help inform on how to minimise the risk of drug resistance developing, maximise sustainable control programme success, and improve diagnostic protocols. We performed a four-generation Schistosoma mansoni praziquantel selection experiment in mice and snails. We used three S. mansoni lines: a praziquantel-resistant isolate (R), a praziquantel-susceptible isolate (S), and a co-infected line (RS), under three treatment regimens: untreated, 25 mg/kg praziquantel, or 50 mg/kg praziquantel. Life-history traits, including parasite adult-worm establishment, survival, reproduction (fecundity), and associated morbidity, were recorded in mice across all four generations. Predictor variables were tested in a series of generalized linear mixed effects models to determine which factors had a significant influence on parasite life-history traits in definitive hosts under different selection regimes. Praziquantel pressure significantly reduced adult-worm burdens across all generations and isolates, including within R-lines. However, previous drug treatment resulted in an increase in adult-worm establishment with increasing generation from P1 to F3. The highest worm numbers were in the co-infected RS line. Praziquantel treatment decreased adult-worm burden, but had a larger negative impact on the mean daily number of miracidia, a proxy for fecundity, across all three parasite isolates. Our predicted cost of resistance was not supported by the traits we measured within the murine host. We did not find evidence for negative adult worm density-dependent effects on fecundity. In contrast, of the adult worms that survived treatment, even low doses of praziquantel significantly reduced adult-worm fecundity. Such reductions in worm fecundity post treatment suggest that egg - based measures of drug efficacy, such as Kato-Katz, may overestimate the short-term effect of praziquantel on adult - worm burdens. These findings have important implications for S. mansoni transmission control, diagnostic protocols, and the potential for undetected selection toward drug resistance.
Bleaching of leaf litter and associated microfungi in subboreal and subalpine forests.
Hagiwara, Yusuke; Matsuoka, Shunsuke; Hobara, Satoru; Mori, Akira S; Hirose, Dai; Osono, Takashi
2015-10-01
Fungal decomposition of lignin leads to the whitening, or bleaching, of leaf litter, especially in temperate and tropical forests, but less is known about such bleaching in forests of cooler regions, such as boreal and subalpine forests. The purposes of the present study were to examine the extent of bleached area on the surface of leaf litter and its variation with environmental conditions in subboreal and subalpine forests in Japan and to examine the microfungi associated with the bleaching of leaf litter by isolating fungi from the bleached portions of the litter. Bleached area accounted for 21.7%-32.7% and 2.0%-10.0% of total leaf area of Quercus crispula and Betula ermanii, respectively, in subboreal forests, and for 6.3% and 18.6% of total leaf area of B. ermanii and Picea jezoensis var. hondoensis, respectively, in a subalpine forest. In subboreal forests, elevation, C/N ratio and pH of the FH layer, and slope aspect were selected as predictor variables for the bleached leaf area. Leaf mass per area and lignin content were consistently lower in the bleached area than in the nonbleached area of the same leaves, indicating that the selective decomposition of acid unhydrolyzable residue (recalcitrant compounds such as lignin, tannins, and cutins) enhanced the mass loss of leaf tissues in the bleached portions. Isolates of a total of 11 fungal species (6 species of Ascomycota and 5 of Basidiomycota) exhibited leaf-litter-bleaching activity under pure culture conditions. Two fungal species (Coccomyces sp. and Mycena sp.) occurred in both subboreal and subalpine forests, which were separated from each other by approximately 1100 km.
Genetic analysis of rice mutants responsible for narrow leaf phenotype and reduced vein number.
Kubo, Fumika Clara; Yasui, Yukiko; Kumamaru, Toshihiro; Sato, Yutaka; Hirano, Hiro-Yuki
2017-03-17
Leaves are a major site for photosynthesis and a key determinant of plant architecture. Rice produces thin and slender leaves, which consist of the leaf blade and leaf sheath separated by the lamina joint. Two types of vasculature, the large and small vascular bundles, run in parallel, together with a strong structure, the midrib. In this paper, we examined the function of four genes that regulate the width of the leaf blade and the vein number: NARROW LEAF1 (NAL1), NAL2, NAL3 and NAL7. We backcrossed original mutants of these genes with the standard wild-type rice, Taichung 65. We then compared the effect of each mutation on similar genetic backgrounds and examined genetic interactions of these genes. The nal1 single mutation and the nal2 nal3 double mutation showed a severe effect on leaf width, resulting in very narrow leaves. Although vein number was also reduced in the nal1 and nal2 nal3 mutants, the small vein number was more strongly reduced than the large vein number. In contrast, the nal7 mutation showed a milder effect on leaf width and vein number, and both the large and small veins were similarly affected. Thus, the genes responsible for narrow leaf phenotype seem to play distinct roles. The nal7 mutation showed additive effects on both leaf width and vein number, when combined with the nal1 single or the nal2 nal3 double mutation. In addition, observations of inner tissues revealed that cell differentiation was partially compromised in the nal2 nal3 nal7 mutant, consistent with the severe reduction in leaf width in this triple mutant.
Spatial variation of deuterium enrichment in bulk water of snowgum leaves.
Santrucek, Jirí; Kveton, Jirí; Setlík, Jirí; Bulícková, Lenka
2007-01-01
Deuterium enrichment of bulk water was measured and modeled in snowgum (Eucalyptus pauciflora Sieber ex Sprengel) leaves grown under contrasting air and soil humidity in arid and wet conditions in a glasshouse. A map of the enrichment was constructed with a resolution of 4 mm by using a newly designed cryodistillation method. There was progressively increasing enrichment in both longitudinal (along the leaf midrib) and transversal (perpendicular to the midrib) directions, most pronounced in the arid-grown leaf. The whole-leaf average of the enrichment was well below the value estimated by the Craig-Gordon model. The discrepancy between model and measurements persisted when the estimates were carried out separately for the leaf base and tip, which differed in temperature and stomatal conductance. The discrepancy was proportional to the transpiration rate, indicating the significance of diffusion-advection interplay (Péclet effect) of deuterium-containing water molecules in small veins close to the evaporating sites in the leaf. Combined Craig-Gordon and desert-river models, with or without the Péclet number, P, were used for predicting the leaf longitudinal enrichment. The predictions without P overestimated the measured values of deltadeuterium. Fixed P value partially improved the coincidence. We suggest that P should vary along the leaf length l to reconcile the modeled data with observations of longitudinal enrichment. Local values of P, P(l), integrating the upstream fraction of water used or the leaf area, substantially improved the model predictions.
A Tissue-Specific Approach to the Analysis of Metabolic Changes in Caenorhabditis elegans
Pujol, Claire; Ipsen, Sabine; Brodesser, Susanne; Mourier, Arnaud; Tolnay, Markus; Frank, Stephan; Trifunović, Aleksandra
2011-01-01
The majority of metabolic principles are evolutionarily conserved from nematodes to humans. Caenorhabditis elegans has widely accelerated the discovery of new genes important to maintain organismic metabolic homeostasis. Various methods exist to assess the metabolic state in worms, yet they often require large animal numbers and tend to be performed as bulk analyses of whole worm homogenates, thereby largely precluding a detailed studies of metabolic changes in specific worm tissues. Here, we have adapted well-established histochemical methods for the use on C. elegans fresh frozen sections and demonstrate their validity for analyses of morphological and metabolic changes on tissue level in wild type and various mutant strains. We show how the worm presents on hematoxylin and eosin (H&E) stained sections and demonstrate their usefulness in monitoring and the identification of morphological abnormalities. In addition, we demonstrate how Oil-Red-O staining on frozen worm cross-sections permits quantification of lipid storage, avoiding the artifact-prone fixation and permeabilization procedures of traditional whole-mount protocols. We also adjusted standard enzymatic stains for respiratory chain subunits (NADH, SDH, and COX) to monitor metabolic states of various C. elegans tissues. In summary, the protocols presented here provide technical guidance to obtain robust, reproducible and quantifiable tissue-specific data on worm morphology as well as carbohydrate, lipid and mitochondrial energy metabolism that cannot be obtained through traditional biochemical bulk analyses of worm homogenates. Furthermore, analysis of worm cross-sections overcomes the common problem with quantification in three-dimensional whole-mount specimens. PMID:22162770
Migratory response of Echinostoma caproni (Digenea: Echinostomatidae) to feeding by ICR mice.
Platt, Thomas R; Quintana, Guadalupe; Rodriguez, Arianne E; Zelmer, Derek A
2013-04-01
The migratory response of Echinostoma caproni to host feeding was examined in female ICR mice. Thirty-six mice were each infected with 20 metacercariae of E. caproni . Twenty-eight days post-infection, food, but not water, was withheld for 24 hr. Mice were haphazardly divided into 4 groups of 9, and each group received one of the following treatments: (1) 0.25 g glucose, (2) access to standard lab chow, (3) 0.5 ml saline, and (4) continued fasting. Three mice from each treatment group were killed 1, 2, and 4 hr post-treatment. The intestine of each mouse was removed, flash-frozen, and stored in a conventional freezer for later examination. Intestines were partially thawed, measured, and opened longitudinally, and the position of each worm, or worm cluster was measured. The intestine was divided into equal 5% segments based on the initial measurement and locations of worms, and worm clusters were recorded from the appropriate section of the intestine for analysis. There was no significant effect of treatment in the position of worms at 1 hr. There was a posterior shift in worm position in all treatment groups at 2 hr, except in the saline-treated mice; however, only worms in the glucose-fed mice were significantly posterior to the unfed controls. From 2 to 4 hr, there was a significant anterior movement of worms in both the glucose and chow-fed mice. The data strongly suggest that E. caproni responds to the initiation of gastric activity of the host by migrating anteriorly in the ileum. The specific stimulus for this migration is unknown.
WORM - WINDOWED OBSERVATION OF RELATIVE MOTION
NASA Technical Reports Server (NTRS)
Bauer, F.
1994-01-01
The Windowed Observation of Relative Motion, WORM, program is primarily intended for the generation of simple X-Y plots from data created by other programs. It allows the user to label, zoom, and change the scale of various plots. Three dimensional contour and line plots are provided, although with more limited capabilities. The input data can be in binary or ASCII format, although all data must be in the same format. A great deal of control over the details of the plot is provided, such as gridding, size of tick marks, colors, log/semilog capability, time tagging, and multiple and phase plane plots. Many color and monochrome graphics terminals and hard copy printer/plotters are supported. The WORM executive commands, menu selections and macro files can be used to develop plots and tabular data, query the WORM Help library, retrieve data from input files, and invoke VAX DCL commands. WORM generated plots are displayed on local graphics terminals and can be copied using standard hard copy capabilities. Some of the graphics features of WORM include: zooming and dezooming various portions of the plot; plot documentation including curve labeling and function listing; multiple curves on the same plot; windowing of multiple plots and insets of the same plot; displaying a specific on a curve; and spinning the curve left, right, up, and down. WORM is written in PASCAL for interactive execution and has been implemented on a DEC VAX computer operating under VMS 4.7 with a virtual memory requirement of approximately 392K of 8 bit bytes. It uses the QPLOT device independent graphics library included with WORM. It was developed in 1988.
Peng, Jianling; Yu, Jianbin; Wang, Hongliang; Guo, Yingqing; Li, Guangming; Bai, Guihua; Chen, Rujin
2011-01-01
Medicago truncatula is a legume species belonging to the inverted repeat lacking clade (IRLC) with trifoliolate compound leaves. However, the regulatory mechanisms underlying development of trifoliolate leaves in legumes remain largely unknown. Here, we report isolation and characterization of fused compound leaf1 (fcl1) mutants of M. truncatula. Phenotypic analysis suggests that FCL1 plays a positive role in boundary separation and proximal-distal axis development of compound leaves. Map-based cloning indicates that FCL1 encodes a class M KNOX protein that harbors the MEINOX domain but lacks the homeodomain. Yeast two-hybrid assays show that FCL1 interacts with a subset of Arabidopsis thaliana BEL1-like proteins with slightly different substrate specificities from the Arabidopsis homolog KNATM-B. Double mutant analyses with M. truncatula single leaflet1 (sgl1) and palmate-like pentafoliata1 (palm1) leaf mutants show that fcl1 is epistatic to palm1 and sgl1 is epistatic to fcl1 in terms of leaf complexity and that SGL1 and FCL1 act additively and are required for petiole development. Previous studies have shown that the canonical KNOX proteins are not involved in compound leaf development in IRLC legumes. The identification of FCL1 supports the role of a truncated KNOX protein in compound leaf development in M. truncatula. PMID:22080596
An Unusual Foreign Body in the Urinary Bladder Mimicking a Parasitic Worm
Schmitt, Bryan H.; Feder, Marc T.; Rokke, Denise L.; Moyer, Thomas P.
2012-01-01
We report an unusual case of a foreign body removed from the urinary bladder of a 63-year-old male which mimicked a parasitic worm. The foreign body was identified as an artificial fishing worm by morphological comparison to a similar commercially produced product and by infrared spectrum analysis. PMID:22535991
Davies, Keith G; Zimmerman, Brian; Dudley, Ed; Newton, Russell P; Hart, John E
2015-03-01
Ambient exposure to a short synthetic peptide has enhanced fecundity (number of offspring) in invertebrates and vertebrates, ostensibly by disinhibiting reproduction. In separate experiments, nematodes (Caenorhabditis elegans) and guppy fish (Poecilia reticulata) were exposed via their aqueous environment to a dissolved synthetic hexamer (6mer) peptide, IEPVFT (EPL036), at a concentration of 1 μmol l(-1). In the case of the worms, peptide was added to their aqueous buffer daily throughout the experiment (14 days); for the guppies, peptide administration was on the first 15 alternate days in a 50 week experiment. Fecundity rose by 79% among the worms. The number of descendants of the treated guppies was more than four times that of controls by week 26 (103 versus 25, including 72 juveniles versus 6), with 15.4% more estimated biomass in the test tank in total (i.e. including founders). It was deduced that treated females bred earlier, at a smaller size, and had larger brood sizes. The total number of fish in the control tank had caught up by termination, but biomass continued to lag the test tank. There were no overt signs of toxicity among either the worms or the fish. Bioinformatics has been unilluminating in explaining these results in terms, for example, of mimicry of an endogenous regulator. A mass spectrometric campaign to identify a receptor, using murine brain for expediency, proved inconclusive. Molecular modelling in silico indicated unexpectedly that the hexamer EPL036 might be acting as an antagonist, to pro-fecundity effect; that is, as a blocker of an inhibitor. This suggests that there awaits discovery an evolutionarily conserved reproductive inhibitor and its (anti-fecundity) receptor. © 2015. Published by The Company of Biologists Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lucius, R.; Textor, G.; Kern, A.
1991-08-01
Jirds (Meriones unguiculatus) were immunized with irradiated (35 krad) stage-3 larvae (L3) of Acanthocheilonema viteae. The induced resistance against homologous challenge infection and the antibody response of the animals were studied. Immunization with 3, 2, or 1 dose of 50 irradiated L3 induced approximately 90% resistance. Immunization with a single dose of only 5 irradiated L3 resulted in 60.8% protection while immunization with a single dose of 25 L3 induced 94.1% protection. The protection induced with 3 doses of 50 irradiated L3 did not decrease significantly during a period of 6 months. Sera of a proportion, but not all resistantmore » jirds, contained antibodies against the surface of vector derived L3 as defined by IFAT. No surface antigens of microfilariae or adult worms were recognized by the sera. Vaccinated animals had antibody responses against antigens in the inner organs of L3 and in the cuticle and reproductive organs of adult worms as shown by IFAT. Immunoblotting with SDS-PAGE-separated L3 antigens and L3-CSN revealed that all sera contained antibodies against two exported antigens of 205 and 68 kDa, and against a nonexported antigen of 18 kDa. The 205-kDa antigen easily degraded into fragments of 165, 140, 125, and 105 kDa which were recognized by resistant jird sera. Various antigens of adult worms, but relatively few antigens of microfilariae, were also recognized. To test the relevance of exported antigens of L3 to resistance, jirds were immunized with L3-CSN together with a mild adjuvant. This immunization induced 67.7% resistance against challenge infection and sera of the immunized animals recognized the 205- and 68-kDa antigens of L3.« less
Antifilarial and Antibiotic Activities of Methanolic Extracts of Melaleuca cajuputi Flowers
Al-Abd, Nazeh M.; Nor, Zurainee Mohamed; Mansor, Marzida; Hasan, MS; Kassim, Mustafa
2016-01-01
We evaluated the activity of methanolic extracts of Melaleuca cajuputi flowers against the filarial worm Brugia pahangi and its bacterial endosymbiont Wolbachia. Anti-Wolbachia activity was measured in worms and in Aedes albopictus Aa23 cells by PCR, electron microscopy, and other biological assays. In particular, microfilarial release, worm motility, and viability were determined. M. cajuputi flower extracts were found to significantly reduce Wolbachia endosymbionts in Aa23 cells, Wolbachia surface protein, and microfilarial release, as well as the viability and motility of adult worms. Anti-Wolbachia activity was further confirmed by observation of degraded and phagocytized Wolbachia in worms treated with the flower extracts. The data provided in vitro and in vivo evidence that M. cajuputi flower extracts inhibit Wolbachia, an activity that may be exploited as an alternative strategy to treat human lymphatic filariasis. PMID:27417081
Worm epidemics in wireless ad hoc networks
NASA Astrophysics Data System (ADS)
Nekovee, Maziar
2007-06-01
A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet.
Unsegmented annelids? Possible origins of four lophotrochozoan worm taxa.
Halanych, Kenneth M; Dahlgren, Thomas G; McHugh, Damhnait
2002-07-01
In traditional classification schemes, the Annelida consists of the Polychaeta and the Clitellata (the latter including the Oligochaeta and Hirudinida). However, recent analyses suggest that annelids are much more diverse than traditionally believed, and that polychaetes are paraphyletic. Specifically, some lesser-known taxa (previously regarded as separate phyla) appear to fall within the annelid radiation. Abundant molecular, developmental, and morphological data show that the Siboglinidae, which includes the formerly recognized Pogonophora and Vestimentifera, are derived annelids; recent data from the Elongation Factor-1α (EF-1α) gene also suggest that echiurids are of annelid ancestry. Further, the phylogenetic origins of two other lesser-known groups of marine worms, the Myzostomida and Sipuncula, have recently been called into question. Whereas some authors advocate annelid affinities, others argue that these taxa do not fall within the annelid radiation. With advances in our understanding of annelid phylogeny, our perceptions of body plan evolution within the Metazoa are changing. The evolution of segmentation probably is more plastic than traditionally believed. However, as our understanding of organismal evolution is being revised, we are also forced to reconsider the specific characters being examined. Should segmentation be considered a developmental process or an ontological endpoint?
2017-01-01
Various carboxylic acid-functionalized poly(N,N-dimethylacrylamide) (PDMAC) macromolecular chain transfer agents (macro-CTAs) were chain-extended with diacetone acrylamide (DAAM) by reversible addition–fragmentation chain transfer (RAFT) aqueous dispersion polymerization at 70 °C and 20% w/w solids to produce a series of PDMAC–PDAAM diblock copolymer nano-objects via polymerization-induced self-assembly (PISA). TEM studies indicate that a PDMAC macro-CTA with a mean degree of polymerization (DP) of 68 or higher results in the formation of well-defined spherical nanoparticles with mean diameters ranging from 40 to 150 nm. In contrast, either highly anisotropic worms or polydisperse vesicles are formed when relatively short macro-CTAs (DP = 40–58) are used. A phase diagram was constructed to enable accurate targeting of pure copolymer morphologies. Dynamic light scattering (DLS) and aqueous electrophoresis studies indicated that in most cases these PDMAC–PDAAM nano-objects are surprisingly resistant to changes in either solution pH or temperature. However, PDMAC40–PDAAM99 worms do undergo partial dissociation to form a mixture of relatively short worms and spheres on adjusting the solution pH from pH 2–3 to around pH 9 at 20 °C. Moreover, a change in copolymer morphology from worms to a mixture of short worms and vesicles was observed by DLS and TEM on heating this worm dispersion to 50 °C. Postpolymerization cross-linking of concentrated aqueous dispersions of PDMAC–PDAAM spheres, worms, or vesicles was performed at ambient temperature using adipic acid dihydrazide (ADH), which reacts with the hydrophobic ketone-functionalized PDAAM chains. The formation of hydrazone groups was monitored by FT-IR spectroscopy and afforded covalently stabilized nano-objects that remained intact on exposure to methanol, which is a good solvent for both blocks. Rheological studies indicated that the cross-linked worms formed a stronger gel compared to linear precursor worms. PMID:28260814
Expression of a unique drug-resistant Hsp90 ortholog by the nematode Caenorhabditis elegans.
David, Cynthia L; Smith, Harold E; Raynes, Deborah A; Pulcini, Elizabeth J; Whitesell, Luke
2003-01-01
In all species studied to date, the function of heat shock protein 90 (Hsp90), a ubiquitous and evolutionarily conserved molecular chaperone, is inhibited selectively by the natural product drugs geldanamycin (GA) and radicicol. Crystal structures of the N-terminal region of yeast and human Hsp90 have revealed that these compounds interact with the chaperone in a Bergerat-type adenine nucleotide-binding fold shared throughout the gyrase, Hsp90, histidine kinase mutL (GHKL) superfamily of adenosine triphosphatases. To better understand the consequences of disrupting Hsp90 function in a genetically tractable multicellular organism, we exposed the soil-dwelling nematode Caenorhabditis elegans to GA under a variety of conditions designed to optimize drug uptake. Mutations in the gene encoding C elegans Hsp90 affect larval viability, dauer development, fertility, and life span. However, exposure of worms to GA produced no discernable phenotypes, although the amino acid sequence of worm Hsp90 is 85% homologous to that of human Hsp90. Consistent with this observation, we found that solid phase-immobilized GA failed to bind worm Hsp90 from worm protein extracts or when translated in a rabbit reticulocyte lysate system. Further, affinity precipitation studies using chimeric worm-vertebrate fusion proteins or worm C-terminal truncations expressed in reticulocyte lysate revealed that the conserved nucleotide-binding fold of worm Hsp90 exhibits the novel ability to bind adenosine triphosphate but not GA. Despite its unusual GA resistance, worm Hsp90 appeared fully functional when expressed in a vertebrate background. It heterodimerized with its vertebrate counterpart and showed no evidence of compromising its essential cellular functions. Heterologous expression of worm Hsp90 in tumor cells, however, did not render them GA resistant. These findings provide new insights into the nature of unusual N-terminal nucleotide-binding fold of Hsp90 and suggest that target-related drug resistance is unlikely to emerge in patients receiving GA-like chemotherapeutic agents.
Yan, Zhihu; Dai, Caili; Feng, Haishun; Liu, Yifei; Wang, Shilu
2014-01-01
The viscoelastic properties of worm-like micelles formed by mixing the cationic surfactant N-hexadecyl-N-methylpiperidinium bromide (C16MDB) with the anionic surfactant sodium laurate (SL) in aqueous solutions were investigated using rheological measurements. The effects of sodium laurate and temperature on the worm-like micelles and the mechanism of the observed shear thinning phenomenon and pseudoplastic behavior were systematically investigated. Additionally, cryogenic transmission electron microscopy images further ascertained existence of entangled worm-like micelles. PMID:25296131
ERIC Educational Resources Information Center
Dias, Alice M.; Ferreira, Maria La Salete
2015-01-01
A simple and ecofriendly procedure was developed in order to prepare extracts from red and green leaves. This procedure enables the separation of yellow, green, and red band pigments and optimizes the previously reported baking soda "supermarket column". The same extract also led to a novel and colorful potato starch column, which can…
Scaling leaf respiration with nitrogen and phosphorus in tropical forests across two continents.
Rowland, Lucy; Zaragoza-Castells, Joana; Bloomfield, Keith J; Turnbull, Matthew H; Bonal, Damien; Burban, Benoit; Salinas, Norma; Cosio, Eric; Metcalfe, Daniel J; Ford, Andrew; Phillips, Oliver L; Atkin, Owen K; Meir, Patrick
2017-05-01
Leaf dark respiration (R dark ) represents an important component controlling the carbon balance in tropical forests. Here, we test how nitrogen (N) and phosphorus (P) affect R dark and its relationship with photosynthesis using three widely separated tropical forests which differ in soil fertility. R dark was measured on 431 rainforest canopy trees, from 182 species, in French Guiana, Peru and Australia. The variation in R dark was examined in relation to leaf N and P content, leaf structure and maximum photosynthetic rates at ambient and saturating atmospheric CO 2 concentration. We found that the site with the lowest fertility (French Guiana) exhibited greater rates of R dark per unit leaf N, P and photosynthesis. The data from Australia, for which there were no phylogenetic overlaps with the samples from the South American sites, yielded the most distinct relationships of R dark with the measured leaf traits. Our data indicate that no single universal scaling relationship accounts for variation in R dark across this large biogeographical space. Variability between sites in the absolute rates of R dark and the R dark : photosynthesis ratio were driven by variations in N- and P-use efficiency, which were related to both taxonomic and environmental variability. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.
Social behaviour and collective motion in plant-animal worms.
Franks, Nigel R; Worley, Alan; Grant, Katherine A J; Gorman, Alice R; Vizard, Victoria; Plackett, Harriet; Doran, Carolina; Gamble, Margaret L; Stumpe, Martin C; Sendova-Franks, Ana B
2016-02-24
Social behaviour may enable organisms to occupy ecological niches that would otherwise be unavailable to them. Here, we test this major evolutionary principle by demonstrating self-organizing social behaviour in the plant-animal, Symsagittifera roscoffensis. These marine aceol flat worms rely for all of their nutrition on the algae within their bodies: hence their common name. We show that individual worms interact with one another to coordinate their movements so that even at low densities they begin to swim in small polarized groups and at increasing densities such flotillas turn into circular mills. We use computer simulations to: (i) determine if real worms interact socially by comparing them with virtual worms that do not interact and (ii) show that the social phase transitions of the real worms can occur based only on local interactions between and among them. We hypothesize that such social behaviour helps the worms to form the dense biofilms or mats observed on certain sun-exposed sandy beaches in the upper intertidal of the East Atlantic and to become in effect a super-organismic seaweed in a habitat where macro-algal seaweeds cannot anchor themselves. Symsagittifera roscoffensis, a model organism in many other areas in biology (including stem cell regeneration), also seems to be an ideal model for understanding how individual behaviours can lead, through collective movement, to social assemblages. © 2016 The Author(s).
Jacques, Christopher N.; Jenks, Jonathan A.; Grovenburg, Troy W.; Klaver, Robert W.; Dubay, Shelli A.
2015-01-01
The meningeal worm (Parelaphostrongylus tenuis) is a nematode parasite that commonly infects white-tailed deer (Odocoileus virginianus; WTD) throughout the deciduous forest biome and deciduous-coniferous ecotone of eastern and central North America; the species is not known to occur west of the grassland biome of central North America. We used county-specific prevalence data to evaluate potential effects of landscape and climatologic factors on the spatial distribution of meningeal worm infection in South Dakota, US. Probability of infection increased 4-fold between eastern and western South Dakota and 1.3-fold for each 1-cm increase in summer precipitation. Sixty-three percent of WTD had only a single worm in the cranium. Expansion of meningeal worm infection across western South Dakota may be inherently low due to the combined effects of arid climate and potential attributes of the Missouri River that limit regional movements by infected WTD. Use of landscape genetic analyses to identify potential relationships between landscape features and population genetic structure of infected deer and parasites may contribute to a greater understanding of regional heterogeneity in meningeal worm infection rates across South Dakota, particularly in counties adjacent to the Missouri River. Future research evaluating heterogeneity in prevalence and intensity of infection between fawn and yearling deer, and the potential role of yearling male deer as dispersal agents of meningeal worms across the Missouri River, also is warranted.
Community assembly of the worm gut microbiome
NASA Astrophysics Data System (ADS)
Gore, Jeff
It has become increasingly clear that human health is strongly influenced by the bacteria that live within the gut, known collectively as the gut microbiome. This complex community varies tremendously between individuals, but understanding the sources that lead to this heterogeneity is challenging. To address this challenge, we are using a bottom-up approach to develop a predictive understanding of how the microbiome assembles and functions within a simple and experimentally tractable gut, the gut of the worm C. elegans. We have found that stochastic community assembly in the C. elegansintestine is sufficient to produce strong inter-worm heterogeneity in community composition. When worms are fed with two neutrally-competing fluorescently labeled bacterial strains, we observe stochastically-driven bimodality in community composition, where approximately half of the worms are dominated by each bacterial strain. A simple model incorporating stochastic colonization suggests that heterogeneity between worms is driven by the low rate at which bacteria successfully establish new intestinal colonies. We can increase this rate experimentally by feeding worms at high bacterial density; in these conditions the bimodality disappears. We have also characterized all pairwise interspecies competitions among a set of eleven bacterial species, illuminating the rules governing interspecies community assembly. These results demonstrate the potential importance of stochastic processes in bacterial community formation and suggest a role for C. elegans as a model system for ecology of host-associated communities.
Vanhoorne, Bart; Decock, Wim; Vranken, Sofie; Lanssens, Thomas; Dekeyzer, Stefanie; Verfaille, Kevin; Horton, Tammy; Kroh, Andreas; Hernandez, Francisco; Mees, Jan
2018-01-01
The World Register of Marine Species (WoRMS) celebrated its 10th anniversary in 2017. WoRMS is a unique database: there is no comparable global database for marine species, which is driven by a large, global expert community, is supported by a Data Management Team and can rely on a permanent host institute, dedicated to keeping WoRMS online. Over the past ten years, the content of WoRMS has grown steadily, and the system currently contains more than 242,000 accepted marine species. WoRMS has not yet reached completeness: approximately 2,000 newly described species per year are added, and editors also enter the remaining missing older names–both accepted and unaccepted–an effort amounting to approximately 20,000 taxon name additions per year. WoRMS is used extensively, through different channels, indicating that it is recognized as a high-quality database on marine species information. It is updated on a daily basis by its Editorial Board, which currently consists of 490 taxonomic and thematic experts located around the world. Owing to its unique qualities, WoRMS has become a partner in many large-scale initiatives including OBIS, LifeWatch and the Catalogue of Life, where it is recognized as a high-quality and reliable source of information for marine taxonomy. PMID:29624577
Census of bacterial microbiota associated with the glacier ice worm Mesenchytraeus solifugus.
Murakami, Takumi; Segawa, Takahiro; Bodington, Dylan; Dial, Roman; Takeuchi, Nozomu; Kohshima, Shiro; Hongoh, Yuichi
2015-03-01
The glacier ice worm, Mesenchytraeus solifugus, is a unique annelid, inhabiting only snow and ice in North American glaciers. Here, we analyzed the taxonomic composition of bacteria associated with M. solifugus based on the 16S rRNA gene. We analyzed four fixed-on-site and 10 starved ice worm individuals, along with glacier surface samples. In total, 1341 clones of 16S rRNA genes were analyzed for the ice worm samples, from which 65 bacterial phylotypes (99.0% cut-off) were identified. Of these, 35 phylotypes were closely related to sequences obtained from their habitat glacier and/or other components of cryosphere; whereas three dominant phylotypes were affiliated with animal-associated lineages of the class Mollicutes. Among the three, phylotype Ms-13 shared less than 89% similarity with database sequences and was closest to a gut symbiont of a terrestrial earthworm. Using fluorescence in situ hybridization, Ms-13 was located on the gut wall surface of the ice worms. We propose a novel genus and species, 'Candidatus Vermiplasma glacialis', for this bacterium. Our results raise the possibility that the ice worm has exploited indigenous glacier bacteria, while several symbiotic bacterial lineages have maintained their association with the ice worm during the course of adaptive evolution to the permanently cold environment. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
In vitro antischistosomal activity of venom from the Egyptian snake Cerastes cerastes.
Hassan, Ehssan Ahmed; Abdel-Rahman, Mohamed Ahmed; Ibrahim, Mohamed Moussa; Soliman, Maha Farid Mohamed
2016-01-01
We studied the potential in vitro antischistosomal activity of Cerastes cerastes venom on adult Schistosoma mansoni worms. Live specimens of the horned viper snake, C. cerastes were collected from the Aswan Governorate (Egypt). Venom was collected from snakes by manual milking. Worms of S. mansoni were obtained from infected hamsters by perfusion and isolated from blood using phosphate buffer. Mortality rates of worms were monitored after 3 days of exposure to snake venom at LC50 and various sublethal concentrations (10, 5, 2.5µg/ml). Scanning electron microscopy was used to investigate tegumental changes in treated worms after exposure to LC50 doses of venom. The LC50 of C. cerastes venom was 21.5µg/ml. The effect of C. cerastes venom on Schistosoma worms varied according to their sex. The mortality rate of male and female worms after 48-h exposure was 83.3% and 50%, respectively. LC50 of C. cerastes venom induced mild to severe tegumental damage in Schistosoma worms in the form of destruction of the oral sucker, shrinkage and erosion of the tegument, and loss of some tubercle spines. The present study demonstrated that C. cerastes venom exerts potential in vitro antischistosomal activity in a time and dose-dependent manner. These results may warrant further investigations to develop novel schistosomicidal agents from C. cerastes snake venom.
Grunting for worms: reactions of Diplocardia to seismic vibrations
M.A. Callaham
2009-01-01
Harvesting earthworms by a practice called 'worm grunting' is a widespread and profitable business in the southeastern USA. Although a variety of techniques are used, most involve rhythmically scraping a wooden stake driven into the ground, with a fiat metal object. A common assumption is that vibrations cause the worms to surface, but this phenomenon has not...
USDA-ARS?s Scientific Manuscript database
Caenorhabditis elegans secretes a dauer pheromone or daumone composed of ascarylose and a fatty acid side chain, perception of which enables worms to gauge depletion of food or a high worm population density. As a result, worms enter the dauer state, a specific developmental stage capable of surviv...
Worms in the College Classroom: More than Just a Composting Demonstration
ERIC Educational Resources Information Center
Kelley, Rebecca L.
2010-01-01
Although worm bins have been used by K-12 and nonformal educators for decades, there is little evidence of their use in postsecondary education. The ease of use, maintenance, affordability, portability, and diversity of scientific concepts that can be demonstrated with a worm bin make it a valuable tool in college science classrooms. The purpose…
In vitro production of Toxocara canis excretory-secretory (TES) antigen.
Thomas, Divyamol; Jeyathilakan, N; Abdul Basith, S; Senthilkumar, T M A
2016-09-01
Toxocara canis is a widespread gastrointestinal nematode parasite of dogs and cause Toxocara larva migrans, an important zoonotic disease in humans on ingestion of infective eggs. Toxocarosis is one of the few human parasitic diseases whose serodiagnosis uses a standardized antigen, T. canis excretory secretory antigen (TES). The present study describes collection of T. canis adult worm, collection and embryonation of T. canis eggs, hatching and separation of T. canis larvae, in vitro maintenance of T. canis second stage larvae for production of TES, concentration of culture fluid TES and yield of TES in correlation with various methods cited in literature.
Wang, B; Mastro, V C; McLane, W H
2000-12-01
As part of the eradication program for recent introductions of the longhorned beetle Anoplophora glabripennis (Motschulsky) in the United States, wood from infested trees is chipped and incinerated. Two tests were conducted to evaluate the efficiency of chipping wood from infested trees on the survival of the beetle. In the first test, plastic worms were used as surrogates for larvae of the beetle. Plastic worms of different sizes were placed in holes drilled in logs of sugar maple, Acer saccharum Marsh. In a second test, in addition to plastic worms, we used different instars and pupae of gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae); larvae of the beetle Phyllophaga annina Lewis (Coleoptera: Scarabaeidae); and larvae of an unidentified weevil (Coleoptera: Curculionidae). Although chipping did not result in an obvious damage to all plastic worms, it did kill all larvae and pupae of insects placed in holes of maple logs. The overall recovery rate (percent recovered) for the plastic worms was 96% in the first (1997) test, and 71 and 98% for 10 and 40 mm long plastic worms in the second (1998) test, respectively. Logistic regression analysis of the data from the first experiment indicates that larger worms receive more severe damage. Size of logs did not have a significant effect on the level of damage received by plastic worms. All recovered insects were severely damaged after chipping logs and we could not determine recovery rates. Results of the two tests indicate that chipping wood from infested trees without incineration of the resulting chips provides a highly effective method for destroying wood inhabiting insect pests such as A. glabripennis. The elimination of incineration saves considerable resources while effectively eliminating risks associated with movements of wood containing living wood-boring insects.
Operation of an aquatic worm reactor suitable for sludge reduction at large scale.
Hendrickx, Tim L G; Elissen, Hellen H J; Temmink, Hardy; Buisman, Cees J N
2011-10-15
Treatment of domestic waste water results in the production of waste sludge, which requires costly further processing. A biological method to reduce the amount of waste sludge and its volume is treatment in an aquatic worm reactor. The potential of such a worm reactor with the oligochaete Lumbriculus variegatus has been shown at small scale. For scaling up purposes, a new configuration of the reactor was designed, in which the worms were positioned horizontally in the carrier material. This was tested in a continuous experiment of 8 weeks where it treated all the waste sludge from a lab-scale activated sludge process. The results showed a higher worm growth rate compared to previous experiments with the old configuration, whilst nutrient release was similar. The new configuration has a low footprint and allows for easy aeration and faeces collection, thereby making it suitable for full scale application. Copyright © 2011 Elsevier Ltd. All rights reserved.
Dietary and microbiome factors determine longevity in Caenorhabditis elegans
Sánchez-Blanco, Adolfo; Rodríguez-Matellán, Alberto; González-Paramás, Ana; González-Manzano, Susana; Kim, Stuart K.; Mollinedo, Faustino
2016-01-01
Diet composition affects organismal health. Nutrient uptake depends on the microbiome. Caenorhabditis elegans fed a Bacillus subtilis diet live longer than those fed the standard Escherichia coli diet. Here we report that this longevity difference is primarily caused by dietary coQ, an antioxidant synthesized by E. coli but not by B. subtilis. CoQ-supplemented E. coli fed worms have a lower oxidation state yet live shorter than coQ-less B. subtilis fed worms. We showed that mutations affecting longevity for E. coli fed worms do not always lead to similar effects when worms are fed B. subtilis. We propose that coQ supplementation by the E. coli diet alters the worm cellular REDOX homeostasis, thus decreasing longevity. Our results highlight the importance of microbiome factors in longevity, argue that antioxidant supplementation can be detrimental, and suggest that the C. elegans standard E. coli diet can alter the effect of signaling pathways on longevity. PMID:27510225
Face Gear Drive with Spur Involute Pinion: Geometry, Generation by a Worm, Stress Analysis
NASA Technical Reports Server (NTRS)
Litvin, Faydor L.; Fuentes, Alfonso; Zanzi, Claudio; Pontiggia, Matteo; Handschuh, Robert F. (Technical Monitor)
2002-01-01
A face gear drive with a spur involute pinion is considered. The generation of the face gear is based on application of a grinding or cutting worm whereas the conventional method of generation is based on application of an involute shaper. An analytical approach is proposed for the determination of: (1) the worm thread surface; (2) avoidance of singularities of the worm thread surface, (air) dressing of the worm; and (3) determination of stresses of the face-gear drive. A computer program for simulation of meshing and contact of the pinion and face-gear has been developed. Correction of machine-tool settings is proposed for reduction of the shift of the bearing contact caused by misalignment. An automatic development of the model of five contacting teeth has been proposed for stress analysis. Numerical examples for illustration of the developed theory are provided.
Durkovic, Jaroslav; Canová, Ingrid; Lagana, Rastislav; Kucerová, Veronika; Moravcík, Michal; Priwitzer, Tibor; Urban, Josef; Dvorák, Milon; Krajnáková, Jana
2013-02-01
Previous studies have shown that Ophiostoma novo-ulmi, the causative agent of Dutch elm disease (DED), is able to colonize remote areas in infected plants of Ulmus such as the leaf midrib and secondary veins. The objective of this study was to compare the performances in leaf traits between two Dutch elm hybrids 'Groeneveld' and 'Dodoens' which possess a contrasting tolerance to DED. Trait linkages were also tested with leaf mass per area (LMA) and with the reduced Young's modulus of elasticity (MOE) as a result of structural, developmental or functional linkages. Measurements and comparisons were made of leaf growth traits, primary xylem density components, gas exchange variables and chlorophyll a fluorescence yields between mature plants of 'Groeneveld' and 'Dodoens' grown under field conditions. A recently developed atomic force microscopy technique, PeakForce quantitative nanomechanical mapping, was used to reveal nanomechanical properties of the cell walls of tracheary elements such as MOE, adhesion and dissipation. 'Dodoens' had significantly higher values for LMA, leaf tissue thickness variables, tracheary element lumen area (A), relative hydraulic conductivity (RC), gas exchange variables and chlorophyll a fluorescence yields. 'Groeneveld' had stiffer cell walls of tracheary elements, and higher values for water-use efficiency and leaf water potential. Leaves with a large carbon and nutrient investment in LMA tended to have a greater leaf thickness and a higher net photosynthetic rate, but LMA was independent of RC. Significant linkages were also found between the MOE and some vascular traits such as RC, A and the number of tracheary elements per unit area. Strong dissimilarities in leaf trait performances were observed between the examined Dutch elm hybrids. Both hybrids were clearly separated from each other in the multivariate leaf trait space. Leaf growth, vascular and gas exchange traits in the infected plants of 'Dodoens' were unaffected by the DED fungus. 'Dodoens' proved to be a valuable elm germplasm for further breeding strategies.
Papanatsiou, Maria; Amtmann, Anna
2017-01-01
Abstract Stomata are microscopic pores formed by specialized cells in the leaf epidermis and permit gaseous exchange between the interior of the leaf and the atmosphere. Stomata in most plants are separated by at least one epidermal pavement cell and, individually, overlay a single substomatal cavity within the leaf. This spacing is thought to enhance stomatal function. Yet, there are several genera naturally exhibiting stomata in clusters and therefore deviating from the one-cell spacing rule with multiple stomata overlaying a single substomatal cavity. We made use of two Begonia species to investigate whether clustering of stomata alters guard cell dynamics and gas exchange under different light and dark treatments. Begonia plebeja, which forms stomatal clusters, exhibited enhanced kinetics of stomatal conductance and CO2 assimilation upon light stimuli that in turn were translated into greater water use efficiency. Our findings emphasize the importance of spacing in stomatal clusters for gaseous exchange and plant performance under environmentally limited conditions. PMID:28369641
Vicente, J G; Everett, B; Roberts, S J
2006-07-01
ABSTRACT Twenty-five Xanthomonas isolates, including some isolates received as either X. campestris pv. armoraciae or pv. raphani, caused discrete leaf spot symptoms when spray-inoculated onto at least one Brassica oleracea cultivar. Twelve of these isolates and four other Xanthomonas isolates were spray- and pin-inoculated onto 21 different plant species/cultivars including horseradish (Armoracia rusticana), radish (Raphanus sativus), and tomato (Lycopersicon esculentum). The remaining 13 leaf spot isolates were spray-inoculated onto a subset of 10 plant species/cultivars. The leaf spot isolates were very aggressive on several Brassica spp., radish, and tomato causing leaf spots and dark sunken lesions on the middle vein, petiole, and stem. Based on the differential reactions of several Brassica spp. and radish cultivars, the leaf spot isolates were divided into three races, with races 1 and 3 predominating. A differential series was established to determine the race-type of isolates and a gene-for-gene model based on the interaction of two avirulence genes in the pathogen races and two matching resistance genes in the differential hosts is proposed. Repetitive-DNA polymerase chain reaction-based fingerprinting was used to assess the genetic diversity of the leaf spot isolates and isolates of closely related Xanthomonas pathovars. Although there was variability within each race, the leaf spot isolates were clustered separately from the X. campestris pv. campestris isolates. We propose that X. campestris isolates that cause a nonvascular leaf spot disease on Brassica spp. should be identified as pv. raphani and not pv. armoraciae. Race-type strains and a neopathotype strain for X. campestris pv. raphani are proposed.
Ball, Aaron; Sanchez-Azofeifa, Arturo; Portillo-Quintero, Carlos; Rivard, Benoit; Castro-Contreras, Saulo; Fernandes, Geraldo
2015-01-01
Aim The general goal of this study is to investigate and analyze patterns of ecophysiological leaf traits and spectral response among life forms (trees, shrubs and lianas) in the Cerrado ecosystem. In this study, we first tested whether life forms are discriminated through leaf level functional traits. We then explored the correlation between leaf-level plant functional traits and spectral reflectance. Location Serra do Cipo National Park, Minas Gerais, Brazil. Methods Six ecophysiological leaf traits were selected to best characterize differences between life forms in the woody plant community of the Cerrado. Results were compared to spectral vegetation indices to determine if plant groups provide means to separate leaf spectral responses. Results Values obtained from leaf traits were similar to results reported from other tropical dry sites. Trees and shrubs significantly differed from lianas in terms of the percentage of leaf water content and Specific Leaf Area. Spectral indices were insufficient to capture the differences of these key traits between groups, though indices were still adequately correlated to overall trait variation. Conclusion The importance of life forms as biochemical and structurally distinctive groups is a significant finding for future remote sensing studies of vegetation, especially in arid and semi-arid environments. The traits we found as indicative of these groups (SLA and water content) are good candidates for spectral characterization. Future studies need to use the full wavelength (400 nm–2500 nm) in order to capture the potential response of these traits. The ecological linkage to water balance and life strategies encourages these traits as starting points for modeling plant communities using hyperspectral remote sensing. PMID:25692675
Storage effects on genomic DNA in rolled and mature coca leaves.
Johnson, Emanuel L; Kim, Soo-Hyung; Emche, Stephen D
2003-08-01
Rolled and mature leaf tissue was harvested from Erythroxylum coca var. coca Lam. (coca) to determine a method for storage that would maintain DNA with high quality and content up to 50 days. Harvesting coca leaf tissue under Andean field conditions often requires storage from 3 to 10 days before extraction where tissue integrity is lost. All samples of rolled and mature coca leaf tissue were harvested and separately stored fresh in RNAlater for 50 days at 4 degrees, -20 degrees, and 23 degrees C, while similar samples were air-dried for 72 h at 23 degrees C or oven-dried for 72 h at 40 degrees C after storage, before extraction. Triplicate samples of each tissue type were extracted for DNA at 10-day intervals and showed that DNA integrity and content were preserved in leaf tissue stored at 4 degrees and -20 degrees C for 50 days. Rolled and mature leaf tissue stored at 4 degrees, -20 degrees, and 23 degrees C showed insignificant degradation of DNA after 10 days, and by day 50, only leaf tissue stored at 4 degrees and -20 degrees C had not significantly degraded. All air- and oven-dried leaf tissue extracts showed degradation upon drying (day 0) and continuous degradation up to day 50, despite storage conditions. Amplified fragment length polymorphism analysis of DNA from rolled and mature leaf tissue of coca stored at 4 degrees and -20 degrees C for 0, 10, and 50 days showed that DNA integrity and content were preserved. We recommend that freshly harvested rolled or mature coca leaf tissue be stored at 4 degrees, -20 degrees, and 23 degrees C for 10 days after harvest, and if a longer storage is required, then store at 4 degrees or -20 degrees C.
Diurnal variations of vegetation canopy structure
NASA Technical Reports Server (NTRS)
Kimes, D. S.; Kirchner, J. A.
1983-01-01
The significance and magnitude of diurnal variations of vegetation canopy structure are reviewed. Diurnal leaf inclination-azimuth angle distributions of a soybean and cotton canopy were documented using a simple measurement technique. The precision of the measurements was on the order of + or -5 deg for the inclination and + or -14 deg for the azimuth. The experimental results and a review of the literature showed that this distribution can vary significantly on a diurnal basis due to vegetation type, heliotropic leaf movement, environmental conditions, and vegetation stress. The study also showed that it is erroneous to treat two separate distributions of azimuth and inclination angles rather than one three-dimensional distribution of leaf orientation. The latter distribution needs to be routinely collected in studies which document variations of diurnal spectral reflectance with changes in solar zenith angle.
Mathews, Miya Gugulethu; Ajayi, Oyemitan Idris; Opeoluwa, Oyedeji Oyehan; Oluwatobi, Oluwafemi Samuel; Benedicta N, Nkeh-Chungag; Phindile, Songca Sandile; Oyedeji; Omowumi, Adebola
2016-01-01
Pentanisia prunelloides is a medicinal plant widely used to remedy various ailments including infections, fever and rheumatism in Eastern Cape Province of South Africa. There is scanty report on the phytochemical and biological properties of the plant; hence various solvent extracts of the dried plant materials were phytochemically screened, and its aqueous extract evaluated for acute toxicity effect, analgesic and antiinflammatory properties in rodents. Different extracts of both leaf and rhizome were obtained separately with ethanol, methanol and water. Portions of the filtrate were used for qualitative screening of secondary metabolites and remaining portions were concentrated and dried. Dried grounded leaf and rhizome of the plant were also used for quantitative screening for some major components. The aqueous extract of the leaf and rhizome were used for acute toxicity (LD 50 ) test, antiinflammatory and analgesic activities in rodents. The qualitative phytochemical screening showed the presence of several phytoconstituents with saponins, flavonoids and alkaloids constituting highest constituents in the leaf and rhizome. The LD50: of the aqueous extracts (from leaf or rhizome) was found to be ≥5000 mg/kg orally. The leaf and rhizome aqueous extract (250-500 mg/kg) significantly (p<0.01) reduced egg albumin-induced paw oedema and paw licking in mice induced by formalin, signifying antinociceptive and antiinflammatory activities respectively. It is concluded that the leaf and rhizome of P. prunelloides are rich in various phytochemicals which could be associated with their medicinal uses. The aqueous leaf and rhizome extracts are similarly non-toxic orally, showed antiinflammatory and analgesic potentials thus rationalizing its use in folkloric medicine.
Sharma, Pradeep; Matsuda, N; Bajet, N B; Ikegami, M
2011-02-01
Three new begomovirus isolates and one betasatellite were obtained from a tomato plant exhibiting leaf curl symptom in Laguna, the Philippines. Typical begomovirus DNA components representing the three isolates (PH01, PH02 and PH03) were cloned, and their full-length sequences were determined to be 2754 to 2746 nucleotides. The genome organizations of these isolates were similar to those of other Old World monopartite begomoviruses. The sequence data indicated that PH01 and PH02 were variants of strain B of the species Tomato leaf curl Philippines virus, while PH03 was a variant of strain A of the species Tomato leaf curl Philippines virus. These isolates were designated ToLCPV-B[PH:Lag1:06], ToLCPV-B[PH:Lag2:06], and ToLCPV-A[PH:Lag3:06], respectively. Phylogenetic analysis revealed that the present isolates form a separate monophyletic cluster with indigenous begomoviruses reported earlier in the Philippines. A betasatellite isolated from same sample belongs to the betasatellite species Tomato leaf curl Philippines betasatellite and designated Tomato leaf curl Philippines betasatellite-[Philippines:Laguna1:2006], ToLCPHB-[PH:Lag1:06]. When co-inoculated with this betasatellite, tomato leaf curl Philippines virus induced severe symptoms in N. benthamiana and Solanum lycopersicum plants. Using a PVX-mediated transient assay, we found that the C4 and C2 proteins of tomato leaf curl Philippines virus and the βC1 protein of ToLCPHB-[PH:Lag1:06] function as a suppressor of RNA silencing.
NASA Technical Reports Server (NTRS)
Bauer, M. E. (Principal Investigator); Walburg, G.; Daughtry, C. S. T.
1981-01-01
Spectral and agronomic measurements were collected from corn (Zea mays L.) canopies under four nitrogen treatment levels (0, 67, 134, and 202 kg/ha) on 11 dates during 1978 and 12 dates during 1979. Data were analyzed to determine the relationship between the spectral responses of canopies and their argonomic characteristics as well as the spectral separability of the four treatments. Red reflectance was increased, while the near infrared reflectance was decreased for canopies under nitrogen deprivation. Spectral differences between treatments were seen throughout each growing season. The near infrared/red reflectance ratio increased spectral treatment differences over those shown by single band reflectance measures. Of the spectral variables examined, the near infrared/red reflectance ratio most effectively separated the treatments. Differences in spectral response between treatments were attributed to varying soil cover, leaf area index, and leaf pigmentation values, all of which changed with N treatment.
Removal of Thelazia callipaeda from the subconjunctival space.
Yagi, T; Sasoh, M; Kawano, T; Ito, K; Uji, Y; Ando, K
2007-01-01
To report the finding of Thelazia callipaeda within the human subconjunctival space. An 81-year-old man with a history of traumatic conjunctival laceration that occurred 2 years previously had white worms in the subconjunctival space of his right eye. Five worms were removed from the subconjunctival space via a local peritomy, since there was no conjunctival laceration noted during the examination. These worms were identified as T callipaeda. T callipaeda cannot dig holes in the ocular wall due to the lack of hooks or sharp spines within the mouth. Therefore, the authors speculate that these worms entered the subconjunctival space through a conjunctival laceration that had occurred 2 years previously.
Orthotic arm joint. [for use in mechanical arms
NASA Technical Reports Server (NTRS)
Dane, D. H. (Inventor)
1974-01-01
An improved orthopedic (orthotic) arm joint that can be used in various joint of mechanical arms is described. The arm joints includes a worm, which is coupled to an electric motor for rotating a worm gear carried within a rotatable housing. The worm gear is supported on a thrust bearing and the rotatable housing is supported on a radial thrust bearing. A bolt extends through the housing, bearings, and worm gear for securing the device together. A potentiometer extends through the bolt, and is coupled to the rotatable housing for rotating therewith, so as to produce an electrical signal indicating the angular position of the rotatable housing.
Dracunculiasis (guinea worm disease).
Greenaway, Chris
2004-02-17
Dracunculiasis (guinea worm disease) is a parasitic disease that is limited to remote, rural villages in 13 sub-Saharan African countries that do not have access to safe drinking water. It is one the next diseases targeted for eradication by the World Health Organization. Guinea worm disease is transmitted by drinking water containing copepods (water fleas) that are infected with Dracunculiasis medinensis larvae. One year after human ingestion of infected water a female adult worm emerges, typically from a lower extremity, producing painful ulcers that can impair mobility for up to several weeks. This disease occurs annually when agricultural activities are at their peak. Large proportions of economically productive individuals of a village are usually affected simultaneously, resulting in decreased agricultural productivity and economic hardship. Eradication of guinea worm disease depends on prevention, as there is no effective treatment or vaccine. Since 1986, there has been a 98% reduction in guinea worm disease worldwide, achieved primarily through community-based programs. These programs have educated local populations on how to filter drinking water to remove the parasite and how to prevent those with ulcers from infecting drinking-water sources. Complete eradication will require sustained high-level political, financial and community support.
Guinea worm infection in northern Nigeria: reflections on a disease approaching eradication.
Greenwood, Brian; Greenwood, Alice; Bradley, Andrew
2017-05-01
Global eradication of the guinea worm (Dracunculus medinensis) is near, although perhaps delayed a little by the discovery of a transmission cycle in dogs. It is therefore an appropriate time to reflect on the severe impact of this infection on the life of the communities where it was endemic prior to the start of the global eradication programme in 1981. From 1971 to 1974, we conducted a series of unpublished studies on guinea worm in a group of villages in Katsina State, northern Nigeria, where the infection was highly endemic. These studies demonstrated the high rate of infection in affected communities, the frequent recurrence of the infection in some subjects and the long-standing disability that remained in some infected individuals. Immunological studies showed a high level of immediate hypersensitivity to adult worm and larval antigens but a downregulation of Th1-type T-cell responses to worm antigens. Freeing communities such as those described in this article from the scourge of guinea worm infection for good will be an important public health triumph. © 2017 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.
Nawa, Yukifumi; de la Cruz-Otero, María del Carmen; Zazueta-Ramos, Magda Luz; Bojórquez-Contreras, Angel; Sicairos-Félix, Josefina; Campista-León, Samuel; Torres-Montoya, Edith Hilario; Sánchez-Gonzalest, Sergio; Guzmán-Loreto, Roberto; Delgado-Vargas, Francisco; Díaz-Camacho, Sylvia Páz
2009-08-01
Gnathostoma turgidum is a nematode that parasitizes the stomach of opossums, Didelphis virginiana. Despite its wide distribution in the Americas, its natural life cycle is poorly understood. Recently, we found an endemic area for G. turgidum infection in Sinaloa, Mexico (Diaz-Camacho et al., 2009). Based on sporadic surveys for several years, the prevalence was apparently high in summer and extremely low in winter. To confirm that this is really a seasonal variance, we conducted a longitudinal survey on G. turgidum infection in opossums from November 2007 to November 2008. The results showed amazing seasonal changes in the prevalence, with synchronized migration and maturation of worms in opossums. Between February and March, many juvenile worms, with occasional AL3, were found in the liver, but no worms were found in the stomach. Mature adult worms began to appear in the stomach around April and rapidly increased in number toward July, when all worms resided in the stomach. Then, the worms disappeared almost completely by November. These results suggest that G. turgidum is an annual parasite of the opossum, D. virginiana, in Mexico.
Jacques, Christopher N.; Jenks, Jonathan A.; Klaver, Robert W.; Dubay, Shelli A.
2017-01-01
Few studies have evaluated how wetland and forest characteristics influence the prevalence of meningeal worm (Parelaphostrongylus tenuis) infection of deer throughout the grassland biome of central North America. We used previously collected, county-level prevalence data to evaluate associations between habitat characteristics and probability of meningeal worm infection in white-tailed deer (Odocoileus virginianus) across eastern South Dakota, US. The highest-ranked binomial regression model for detecting probability of meningeal worm infection was spring temperature + summer precipitation + percent wetland; weight of evidence (wi=0.71) favored this model over alternative models, though predictive capability was low (Receiver operating characteristic=0.62). Probability of meningeal worm infection increased by 1.3- and 1.6-fold for each 1-cm and 1-C increase in summer precipitation and spring temperature, respectively. Similarly, probability of infection increased 1.2-fold for each 1% increase in wetland habitat. Our findings highlight the importance of wetland habitat in predicting meningeal worm infection across eastern South Dakota. Future research is warranted to evaluate the relationships between climatic conditions (e.g., drought, wet cycles) and deer habitat selection in maintaining P. tenuis along the western boundary of the parasite.
Razzaq, Misbah; Ahmad, Jamil
2015-01-01
Internet worms are analogous to biological viruses since they can infect a host and have the ability to propagate through a chosen medium. To prevent the spread of a worm or to grasp how to regulate a prevailing worm, compartmental models are commonly used as a means to examine and understand the patterns and mechanisms of a worm spread. However, one of the greatest challenge is to produce methods to verify and validate the behavioural properties of a compartmental model. This is why in this study we suggest a framework based on Petri Nets and Model Checking through which we can meticulously examine and validate these models. We investigate Susceptible-Exposed-Infectious-Recovered (SEIR) model and propose a new model Susceptible-Exposed-Infectious-Recovered-Delayed-Quarantined (Susceptible/Recovered) (SEIDQR(S/I)) along with hybrid quarantine strategy, which is then constructed and analysed using Stochastic Petri Nets and Continuous Time Markov Chain. The analysis shows that the hybrid quarantine strategy is extremely effective in reducing the risk of propagating the worm. Through Model Checking, we gained insight into the functionality of compartmental models. Model Checking results validate simulation ones well, which fully support the proposed framework. PMID:26713449
Razzaq, Misbah; Ahmad, Jamil
2015-01-01
Internet worms are analogous to biological viruses since they can infect a host and have the ability to propagate through a chosen medium. To prevent the spread of a worm or to grasp how to regulate a prevailing worm, compartmental models are commonly used as a means to examine and understand the patterns and mechanisms of a worm spread. However, one of the greatest challenge is to produce methods to verify and validate the behavioural properties of a compartmental model. This is why in this study we suggest a framework based on Petri Nets and Model Checking through which we can meticulously examine and validate these models. We investigate Susceptible-Exposed-Infectious-Recovered (SEIR) model and propose a new model Susceptible-Exposed-Infectious-Recovered-Delayed-Quarantined (Susceptible/Recovered) (SEIDQR(S/I)) along with hybrid quarantine strategy, which is then constructed and analysed using Stochastic Petri Nets and Continuous Time Markov Chain. The analysis shows that the hybrid quarantine strategy is extremely effective in reducing the risk of propagating the worm. Through Model Checking, we gained insight into the functionality of compartmental models. Model Checking results validate simulation ones well, which fully support the proposed framework.
Polycyclic aromatic hydrocarbons in Saccoglossus kowalewskyi (Agassiz)
NASA Astrophysics Data System (ADS)
Carey, D. A.; Farrington, J. W.
1989-08-01
Hydrocarbon extracts were analyzed from Saccoglossus kowalewskyi, a deposit-feeding enteropneust worm, and from surface sediments from Cape Cod, MA. Worms were held in experimental aquaria in sieved sediments and flowing seawater for four months and then fed sediments mixed with creosote, lampblack or clean sediment for two weeks as analogues of sediments containing degraded oil and pyrogenic compounds. Worms from all treatments contained polyaromatic hydrocarbons (PAHs) in amounts and composition that indicate that the worms were contaminated with weathered No. 2 fuel oil before our experimental treatment and that the contamination persisted for four months in clean conditions. The contamination was not detected in the clean sediments used in the experiment. The worms accumulated steroid transformation products in greater abundance than the odd chain n-alkanes that dominated the sediment extractions. This may indicate selective assimilation of algal detritus and microbial products over salt marsh detritus. Worms, actively feeding during the experiment, contained 1-3 × 10 -6 g g -1 dry weight of unknown brominated compounds which were not detected in the sediments. These compounds are similar to bromopyrroles found elsewhere in enteropneusts, polychaetes and bacteria and may cause substantial interference in analyses for some industrial pollutants.
NASA Astrophysics Data System (ADS)
Leung, Kawai; Mohammadi, Aylia; Ryu, William; Nemenman, Ilya
In animals, we must infer the pain level from experimental characterization of behavior. This is not trivial since behaviors are very complex and multidimensional. To establish C.elegans as a model for pain research, we propose for the first time a quantitative model that allows inference of a thermal nociceptive stimulus level from the behavior of an individual worm. We apply controlled levels of pain by locally heating worms with an infrared laser and capturing the subsequent behavior. We discover that the behavioral response is a product of stereotypical behavior and a nonlinear function of the strength of stimulus. The same stereotypical behavior is observed in normal, anesthetized and mutated worms. From this result we build a Bayesian model to infer the strength of laser stimulus from the behavior. This model allows us to measure the efficacy of anaesthetization and mutation by comparing the inferred strength of stimulus. Based on the measured nociceptive escape of over 200 worms, our model is able to significantly differentiate normal, anaesthetized and mutated worms with 40 worm samples. This work was partially supported by NSF Grant No. IOS/1208126 and HFSP Grant No. RGY0084/.
NASA Technical Reports Server (NTRS)
Alexander, June; Corwin, Edward; Lloyd, David; Logar, Antonette; Welch, Ronald
1996-01-01
This research focuses on a new neural network scene classification technique. The task is to identify scene elements in Advanced Very High Resolution Radiometry (AVHRR) data from three scene types: polar, desert and smoke from biomass burning in South America (smoke). The ultimate goal of this research is to design and implement a computer system which will identify the clouds present on a whole-Earth satellite view as a means of tracking global climate changes. Previous research has reported results for rule-based systems (Tovinkere et at 1992, 1993) for standard back propagation (Watters et at. 1993) and for a hierarchical approach (Corwin et al 1994) for polar data. This research uses a hierarchical neural network with don't care conditions and applies this technique to complex scenes. A hierarchical neural network consists of a switching network and a collection of leaf networks. The idea of the hierarchical neural network is that it is a simpler task to classify a certain pattern from a subset of patterns than it is to classify a pattern from the entire set. Therefore, the first task is to cluster the classes into groups. The switching, or decision network, performs an initial classification by selecting a leaf network. The leaf networks contain a reduced set of similar classes, and it is in the various leaf networks that the actual classification takes place. The grouping of classes in the various leaf networks is determined by applying an iterative clustering algorithm. Several clustering algorithms were investigated, but due to the size of the data sets, the exhaustive search algorithms were eliminated. A heuristic approach using a confusion matrix from a lightly trained neural network provided the basis for the clustering algorithm. Once the clusters have been identified, the hierarchical network can be trained. The approach of using don't care nodes results from the difficulty in generating extremely complex surfaces in order to separate one class from all of the others. This approach finds pairwise separating surfaces and forms the more complex separating surface from combinations of simpler surfaces. This technique both reduces training time and improves accuracy over the previously reported results. Accuracies of 97.47%, 95.70%, and 99.05% were achieved for the polar, desert and smoke data sets.
Response of vegetation indices to changes in three measures of leaf water stress
NASA Technical Reports Server (NTRS)
Cohen, Warren B.
1991-01-01
The responses of vegetation indices to changes in water stress were evaluated in two separate laboratory experiments. In one experiment the normalized difference vegetation index (NDVI), the near-IR to red ratio (near-IR/red), the Infrared Index (II), and the Moisture Stress Index (MSI) were more highly correlated to leaf water potential in lodgepole pine branches than were the Leaf Water Content Index (LWCI), the mid-IR ratio (Mid-IR), or any of the single Thematic Mapper (TM) bands. In the other experiment, these six indices and the TM Tasseled Cap brightness, greenness, and wetness indices responded to changes in leaf relative water content (RWC) differently than they responded to changes in leaf water content (WC) of three plant species, and the responses were dependent on how experimental replicates were pooled. With no pooling, the LWCI was the most highly correlated index to both RWC and WC among replications, followed by the II, MSI, and wetness. Only the LWCI was highly correlated to RWC and WC when replications were pooled within species. With among species pooling the LWCI was the only index highly correlated with RWC, while the II, MSI, Mid-IR, and wetness were most highly correlated with WC.
Worm Disease Profile of Primary School Children
NASA Astrophysics Data System (ADS)
Hartati; Destriani; Victoria, A. R.
2018-01-01
The result of an elementary study of relations between disease symptoms and signs with the wormy occurrence child at Elementary School in Ilir Barat II Subdistrict of Palembang in concerned in this research amount to 200 people from the population of 4200 people of a child in elementary school. The result indicates that the child roommates infested worm marked with a few symptoms like passion eat to Decrease the puking pain in the home of stomach after eating, diarrhea, defecate with the mucus and bleed the purities at the anus before controlled from some worm type of there no difference having a meaning between child roommates worm infested with the child roommates do not infest worm (P > 0.05). Symptom vomit got more amount by having a meaning a child by infested is Trichuris (RO > 2.669, P < 0/005). The result of infested Tricuris generate the more amount of symptoms lust to eat to Decrease by having a meaning of Compared to the which do not infest Trichuris (RO = 3.772; CI 95% = 1.214 to 11.726; P = 0.016) symptoms lust to eat to Decrease and more amount diarrhea got at Infest oxyuris with the special sign of purities at nighttime anus (RO = 0.557; 85% CI = 0.166 to 2.168). The risk of the happening of unfavorable nutrition According to BB / U and Also TB / U growing niche to more amount (having a meaning) at child roommates worm infested by a child Compared to the which do not infest worm.
Stevens, Richard; Kerans, B.L.; Lemmon, J. C.; Rasmussen, Charlotte
2001-01-01
The aquatic oligochaete Tubifex tubifex is an obligate host of Myxobolus cerebralis, the causative agent of salmonid whirling disease. Tubifex tubifex can become infected by ingesting myxospores ofM. cerebralis that have been released into sediments upon death and decomposition of infected salmonids. Infected worms release triactinomyxons into the water column that then infect salmonids. How the dose of myxospores ingested by T. tubifex influences parasite proliferation and the worm host are not well understood. Using replicated laboratory experiments, we examined how differing doses of myxospores (50, 500, 1,000 per worm) influenced triactinomyxon production and biomass, abundance, and individual weight of 2 geographically distinct populations of T. tubifex. Worm populations produced differing numbers of triactinomyxons, but, within a population, the production did not differ among myxospore doses. At the lowest myxospore dose, 1 worm population produced 45 times more triactinomyxons than myxospores received, whereas the other produced only 6 times more triactinomyxons than myxospores. Moreover, total T. tubifex biomass, abundance, and individual weight were lower among worms receiving myxospores than in myxospore-free controls. Thus, T. tubifex populations differ in ability to support the replication of M. cerebralis, and infection has measurable consequences on fitness of the worm host. These results suggest that variability in whirling disease severity observed in wild salmonid populations may partially be attributed to differences in T. tubifex populations.
Identification of animal behavioral strategies by inverse reinforcement learning.
Yamaguchi, Shoichiro; Naoki, Honda; Ikeda, Muneki; Tsukada, Yuki; Nakano, Shunji; Mori, Ikue; Ishii, Shin
2018-05-01
Animals are able to reach a desired state in an environment by controlling various behavioral patterns. Identification of the behavioral strategy used for this control is important for understanding animals' decision-making and is fundamental to dissect information processing done by the nervous system. However, methods for quantifying such behavioral strategies have not been fully established. In this study, we developed an inverse reinforcement-learning (IRL) framework to identify an animal's behavioral strategy from behavioral time-series data. We applied this framework to C. elegans thermotactic behavior; after cultivation at a constant temperature with or without food, fed worms prefer, while starved worms avoid the cultivation temperature on a thermal gradient. Our IRL approach revealed that the fed worms used both the absolute temperature and its temporal derivative and that their behavior involved two strategies: directed migration (DM) and isothermal migration (IM). With DM, worms efficiently reached specific temperatures, which explains their thermotactic behavior when fed. With IM, worms moved along a constant temperature, which reflects isothermal tracking, well-observed in previous studies. In contrast to fed animals, starved worms escaped the cultivation temperature using only the absolute, but not the temporal derivative of temperature. We also investigated the neural basis underlying these strategies, by applying our method to thermosensory neuron-deficient worms. Thus, our IRL-based approach is useful in identifying animal strategies from behavioral time-series data and could be applied to a wide range of behavioral studies, including decision-making, in other organisms.
Mallick, Chhanda; Chatterjee, Kausik; Guhabiswas, Mehuli; Ghosh, Debidas
2007-02-16
We evaluated the antihyperglycaemic properties of aqueous-methanolic (40:60) extract of root of Musa paradisiaca and leaf of Coccinia indica in separate as well as in composite manner by conducting experiment on streptozotocin-induced diabetic rats. We measured food and water intake ability, the fasting blood glucose level, glucose tolerance, activities of important carbohydrate metabolic enzymes like glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, hexokinase in liver along with quantification of glycogen in liver and in skeletal muscle and serum insulin level. We noted that after treatment of aqueous methanolic extract of above plant parts in separate as well as in composite manner at a concentration of 80 mg/100 g body weight/day to streptozotocin-induced diabetic rat resulted in a significant remedial effect on blood glucose level as well as carbohydrate metabolic enzymes and the quantity of liver and skeletal muscle glycogen. Serum insulin level that was diminished in streptozotocin-induced diabetic rat recovered significantly after the co-administration of extract of above plant parts. All the above parameters showed a more potent remedial effect after composite extract treatment with respect to separate treatment and none of the extract has any general metabolic toxicity induction.
Breakdown of middle lamella pectin by (●) OH during rapid abscission in Azolla.
Yamada, Yoshiya; Koibuchi, Mizuki; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji
2015-08-01
Azolla, a small water fern, abscises its roots and branches within 30 min upon treatment with various stresses. This study was conducted to test whether, in the rapid abscission that occurs in Azolla, breakdown of wall components of abscission zone cells by (●) OH is involved. Experimentally generated (●) OH caused the rapid separation of abscission zone cells from detached roots and the rapid shedding of roots from whole plants. Electron microscopic observations revealed that (●) OH rapidly and selectively dissolved a well-developed middle lamella between abscission zone cells and resultantly caused rapid cell separation and shedding. Treatment of abscission zones of Impatiens leaf petiole with (●) OH also accelerated the separation of abscission zone cells. However, compared with that of Azolla roots, accelerative effects in Impatiens were weak. A large amount of (●) OH was cytochemically detected in abscission zone cells both of Azolla roots and of Impatiens leaf petioles. These results suggest that (●) OH is involved in the cell separation process not only in the rapid abscission in Azolla but also in the abscission of Impatiens. However, for rapid abscission to occur, a well-developed middle lamella, a unique structure, which is sensitive to the attack of (●) OH, might be needed. © 2015 John Wiley & Sons Ltd.
Zhang, Yong-Jiang; Rockwell, Fulton E.; Wheeler, James K.; Holbrook, N. Michele
2014-01-01
Declines in leaf hydraulic conductance (Kleaf) with increasing water stress have been attributed to cavitation of the leaf xylem. However, in the leaves of conifers, the reversible collapse of transfusion tracheids may provide an alternative explanation. Using Taxus baccata, a conifer species without resin, we developed a modified rehydration technique that allows the separation of declines in Kleaf into two components: one reversible and one irreversible upon relaxation of water potential to −1 MPa. We surveyed leaves at a range of water potentials for evidence of cavitation using cryo-scanning electron microscopy and quantified dehydration-induced structural changes in transfusion tracheids by cryo-fluorescence microscopy. Irreversible declines in Kleaf did not occur until leaf water potentials were more negative than −3 MPa. Declines in Kleaf between −2 and −3 MPa were reversible and accompanied by the collapse of transfusion tracheids, as evidenced by cryo-fluorescence microscopy. Based on cryo-scanning electron microscopy, cavitation of either transfusion or xylem tracheids did not contribute to declines in Kleaf in the reversible range. Moreover, the deformation of transfusion tracheids was quickly reversible, thus acting as a circuit breaker regulating the flux of water through the leaf vasculature. As transfusion tissue is present in all gymnosperms, the reversible collapse of transfusion tracheids may be a general mechanism in this group for the protection of leaf xylem from excessive loads generated in the living leaf tissue. PMID:24948828
Ellsworth, Patrick Z; Ellsworth, Patrícia V; Cousins, Asaph B
2017-06-15
Leaf carbon and oxygen isotope ratios can potentially provide a time-integrated proxy for stomatal conductance (gs) and transpiration rate (E), and can be used to estimate transpiration efficiency (TE). In this study, we found significant relationships of bulk leaf carbon isotopic signature (δ13CBL) and bulk leaf oxygen enrichment above source water (Δ18OBL) with gas exchange and TE in the model C4 grasses Setaria viridis and S. italica. Leaf δ13C had strong relationships with E, gs, water use, biomass, and TE. Additionally, the consistent difference in δ13CBL between well-watered and water-limited plants suggests that δ13CBL is effective in separating C4 plants with different availability of water. Alternatively, the use of Δ18OBL as a proxy for E and TE in S. viridis and S. italica was problematic. First, the oxygen isotopic composition of source water, used to calculate leaf water enrichment (Δ18OLW), was variable with time and differed across water treatments. Second, water limitations changed leaf size and masked the relationship of Δ18OLW and Δ18OBL with E. Therefore, the data collected here suggest that δ13CBL but not Δ18OBL may be an effective proxy for TE in C4 grasses. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Bauerle, William L.; Bowden, Joseph D.
2011-01-01
A spatially explicit mechanistic model, MAESTRA, was used to separate key parameters affecting transpiration to provide insights into the most influential parameters for accurate predictions of within-crown and within-canopy transpiration. Once validated among Acer rubrum L. genotypes, model responses to different parameterization scenarios were scaled up to stand transpiration (expressed per unit leaf area) to assess how transpiration might be affected by the spatial distribution of foliage properties. For example, when physiological differences were accounted for, differences in leaf width among A. rubrum L. genotypes resulted in a 25% difference in transpiration. An in silico within-canopy sensitivity analysis was conducted over the range of genotype parameter variation observed and under different climate forcing conditions. The analysis revealed that seven of 16 leaf traits had a ≥5% impact on transpiration predictions. Under sparse foliage conditions, comparisons of the present findings with previous studies were in agreement that parameters such as the maximum Rubisco-limited rate of photosynthesis can explain ∼20% of the variability in predicted transpiration. However, the spatial analysis shows how such parameters can decrease or change in importance below the uppermost canopy layer. Alternatively, model sensitivity to leaf width and minimum stomatal conductance was continuous along a vertical canopy depth profile. Foremost, transpiration sensitivity to an observed range of morphological and physiological parameters is examined and the spatial sensitivity of transpiration model predictions to vertical variations in microclimate and foliage density is identified to reduce the uncertainty of current transpiration predictions. PMID:21617246
Junker, Laura V; Ensminger, Ingo
2016-12-01
Rapid developments in remote-sensing of vegetation and high-throughput precision plant phenotyping promise a range of real-life applications using leaf optical properties for non-destructive assessment of plant performance. Use of leaf optical properties for assessing plant performance requires the ability to use photosynthetic pigments as proxies for physiological properties and the ability to detect these pigments fast, reliably and at low cost. We describe a simple and cost-effective protocol for the rapid analysis of chlorophylls, carotenoids and tocopherols using high-performance liquid chromatography (HPLC). Many existing methods are based on the expensive solvent acetonitrile, take a long time or do not include lutein epoxide and α-carotene. We aimed to develop an HPLC method which separates all major chlorophylls and carotenoids as well as lutein epoxide, α-carotene and α-tocopherol. Using a C 30 -column and a mobile phase with a gradient of methanol, methyl-tert-butyl-ether (MTBE) and water, our method separates the above pigments and isoprenoids within 28 min. The broad applicability of our method is demonstrated using samples from various plant species and tissue types, e.g. leaves of Arabidopsis and avocado plants, several deciduous and conifer tree species, various crops, stems of parasitic dodder, fruit of tomato, roots of carrots and Chlorella algae. In comparison to previous methods, our method is very affordable, fast and versatile and can be used to analyze all major photosynthetic pigments that contribute to changes in leaf optical properties and which are of interest in most ecophysiological studies. © 2016 Scandinavian Plant Physiology Society.
2007-02-01
antisense RNA for suppressing gene expression in nematode worms (Caenorhabditis elegans) 2. This was followed by the introduction of dsRNA into worms...When single-stranded antisense RNA and double stranded RNA was introduced into worms, they found that dsRNA was more effective than either strand...RISC ( RNA -induced silencing complex), which contains helicase activity that unwinds the two strands 3 of RNA molecules, allowing the antisense
Worms Eat My Garbage. How To Set Up and Maintain a Worm Composting System. First Edition.
ERIC Educational Resources Information Center
Appelhof, Mary
This book is a resource for parents and teachers who want to teach about recycling and composting by setting up and maintaining a worm composting system. It is designed to be a detailed yet simple manual of vermicomposting. The manual covers the basics of vermicomposting and answers such questions as where to store a composting container, what…
NASA Astrophysics Data System (ADS)
Tee, Ling Fei; Neoh, Hui-min; Then, Sue Mian; Murad, Nor Azian; Asillam, Mohd Fairos; Hashim, Mohd Helmy; Nathan, Sheila; Jamal, Rahman
2017-11-01
Studies of multigenerational Caenorhabditis elegans exposed to long-term spaceflight have revealed expression changes of genes involved in longevity, DNA repair, and locomotion. However, results from spaceflight experiments are difficult to reproduce as space missions are costly and opportunities are rather limited for researchers. In addition, multigenerational cultures of C. elegans used in previous studies contribute to mixture of gene expression profiles from both larvae and adult worms, which were recently reported to be different. Usage of different culture media during microgravity simulation experiments might also give rise to differences in the gene expression and biological phenotypes of the worms. In this study, we investigated the effects of simulated microgravity on the gene expression and biological phenotype profiles of a single generation of C. elegans worms cultured on 2 different culture media. A desktop Random Positioning Machine (RPM) was used to simulate microgravity on the worms for approximately 52 to 54 h. Gene expression profile was analysed using the Affymetrix GeneChip® C. elegans 1.0 ST Array. Only one gene (R01H2.2) was found to be downregulated in nematode growth medium (NGM)-cultured worms exposed to simulated microgravity. On the other hand, eight genes were differentially expressed for C. elegans Maintenance Medium (CeMM)-cultured worms in microgravity; six were upregulated, while two were downregulated. Five of the upregulated genes (C07E3.15, C34H3.21, C32D5.16, F35H8.9 and C34F11.17) encode non-coding RNAs. In terms of biological phenotype, we observed that microgravity-simulated worms experienced minimal changes in terms of lifespan, locomotion and reproductive capabilities in comparison with the ground controls. Taking it all together, simulated microgravity on a single generation of C. elegans did not confer major changes to their gene expression and biological phenotype. Nevertheless, exposure of the worms to microgravity lead to higher expression of non-coding RNA genes, which may play an epigenetic role in the worms during longer terms of microgravity exposure.
Thioredoxin Glutathione Reductase as a Novel Drug Target: Evidence from Schistosoma japonicum
Xie, ShuYing; Qian, ChunYan; Wang, Jie; Zhang, Wei; Yin, XuRen; Hua, ZiChun; Yu, ChuanXin
2012-01-01
Background Schistosomiasis remains a major public health concern affecting billions of people around the world. Currently, praziquantel is the only drug of choice for treatment of human schistosomiasis. The emergence of drug resistance to praziquantel in schistosomes makes the development of novel drugs an urgent task. Thioredoxin glutathione reductase (TGR) enzymes in Schistosoma mansoni and some other platyhelminths have been identified as alternative targets. The present study was designed to confirm the existense and the potential value of TGR as a target for development of novel antischistosomal agents in Schistosoma japonicum, a platyhelminth endemic in Asia. Methods and Findings After cloning the S. japonicum TGR (SjTGR) gene, the recombinant SjTGR selenoprotein was purified and characterized in enzymatic assays as a multifunctional enzyme with thioredoxin reductase (TrxR), glutathione reductase (GR) and glutaredoxin (Grx) activities. Immunological and bioinformatic analyses confirmed that instead of having separate TrxR and GR proteins in mammalian, S. japonicum only encodes TGR, which performs the functions of both enzymes and plays a critical role in maintaining the redox balance in this parasite. These results were in good agreement with previous findings in Schistosoma mansoni and some other platyhelminths. Auranofin, a known inhibitor against TGR, caused fatal toxicity in S. japonicum adult worms in vitro and reduced worm and egg burdens in S. japonicum infected mice. Conclusions Collectively, our study confirms that a multifunctional enzyme SjTGR selenoprotein, instead of separate TrxR and GR enzymes, exists in S. japonicum. Furthermore, TGR may be a potential target for development of novel agents against schistosomes. This assumption is strengthened by our demonstration that the SjTGR is an essential enzyme for maintaining the thiol-disulfide redox homeostasis of S. japonicum. PMID:22384025
NASA Astrophysics Data System (ADS)
Fytilis, N.; Lamb, R.; Kerans, B.; Stevens, L.; Rizzo, D. M.
2011-12-01
Fish diseases are often caused by waterborne parasites, making them ideal systems for modeling the non-linear relationships between disease dynamics, stream dwelling oligochaete communities and geochemical features. Myxobolus cerebralis, the causative agent of whirling disease in salmonid fishes, has been a major contributor to the loss of wild rainbow trout populations in numerous streams within the Intermountain West. The parasite alternates between an invertebrate and vertebrate host, being transmitted between the sediment feeding worm Tubifex tubifex (T.tubifex) and salmonid fishes. Worm community biodiversity and abundance are influenced by biogeochemical features and have been linked to disease severity in fish. The worm (T.tubifex) lives in communities with 3-4 other types of worms in stream sediments. Unfortunately, taxonomic identification of oligochaetes is largely dependent on morphological characteristics of sexually mature adults. We have collected and identified ~700 worms from eight sites using molecular genetic probes and a taxonomic key. Additionally, ~1700 worms were identified using only molecular genetic probes. To facilitate distinguishing among tubificids, we developed two multiplex molecular genetic probe-based quantitative polymerase reaction (qPCR) assays to assess tubificid communities in the study area. Similar qPCR techniques specific for M.cerebralis used to determine if individual worms were infected with the parasite. We show how simple Bayesian analysis of the qPCR data can predict the worm community structure and reveal relationships between biodiversity of host communities and host-parasite dynamics. To our knowledge, this is the first study that combines molecular data of both the host and the parasite to examine the effects of host community structure on the transmission of a parasite. Our work can be extended to examine the links between worm community structure and biogeochemical features using molecular genetics and Bayesian statistics to assist in identifying new nonlinear relationships and suggest new subsets of input parameters. Future work includes the development of a new complex systems tool capable of assimilating biological DNA sequence data and biogeochemical features using artificial neural networks and Bayesian analysis. The methodologies developed here helped mine the relationships between biodiversity of host communities and host-parasite dynamics. The results from our study will be useful to managers and researchers for assessing the risk of whirling disease in drainages where tubificid community composition data are needed. This collaboration between modelers, field ecologists and geneticists will prove useful in modeling efforts and will enable more effective, high-volume hypothesis generation. The ability to characterize areas of high whirling disease risk is essential for improving our understanding of the dynamics of M.cerebralis such that appropriate management strategies can be implemented.
Li, Qian; Liu, Zeng-Wen; Du, Liang-Zhen
2012-03-01
In this study, the leaf litters of Populus simonii and other 11 tree species were put into soil separately or in mixture after grinding, and incubated in laboratory to analyze the effects of their decomposition on soil properties and the interactions between the litters decomposition. The decomposition of each kind of the leaf litters in soil increased the soil urease, dehydrogenase, and phosphatase activities and the soil organic matter and available N contents markedly, but had greater differences in the effects on the soil available P content and CEC. The decomposition of the leaf litters of Caragana microphylla and of Amorpha fruticosa showed obvious effects in improving soil properties. The decomposition of the mixed leaf litters of P. simonii and Pinus tabulaeformis, Platycladus orientalis, Robinia pseudoacacia, or Ulmus pumila showed interactive promotion effects on the abundance of soil microbes, and that of the mixed leaf litters of P. simonii and P. orientalis or C. microphylla showed interactive promotion effects on the soil organic matter, available P, and available K contents and soil CEC but interactive inhibition effects on the activities of most of the soil enzymes tested. The decomposition of the mixed leaf litters of P. simonii and Larix principis-rupprechtii showed interactive promotion effects on the activities of most of the soil enzymes and soil nutrient contents, while that of the mixed leaf litters of P. simonii and P. sylvestris var. mongolica showed interactive inhibition effects. Overall, the decomposition of the mixed leaf litters of P. simo- nii and U. pumila, P. tabulaeformis, L. principis-rupprechtii, or R. pseudoacacia could improve soil quality, but the mixed leaf litters of P. simonii and P. orientalis, C. microphylla, P. sylvestris var. mongolica, Hippophae rhamnoides, or A. fruticosa showed an interactive inhibition effect during their decomposition.
Marine worms (genus Osedax) colonize cow bones
Jones, William J; Johnson, Shannon B; Rouse, Greg W; Vrijenhoek, Robert C
2007-01-01
Bone-eating worms of the genus Osedax colonized and grew on cow bones deployed at depths ranging from 385 to 2893 m in Monterey Bay, California. Colonization occurred as rapidly as two months following deployment of the cow bones, similar to the time it takes to colonize exposed whalebones. Some Osedax females found on the cow bones were producing eggs and some hosted dwarf males in their tubes. Morphological and molecular examinations of these worms confirmed the presence of six Osedax species, out of the eight species presently known from Monterey Bay. The ability of Osedax species to colonize, grow and reproduce on cow bones challenges previous notions that these worms are ‘whale-fall specialists.’ PMID:18077256
Marine worms (genus Osedax) colonize cow bones.
Jones, William J; Johnson, Shannon B; Rouse, Greg W; Vrijenhoek, Robert C
2008-02-22
Bone-eating worms of the genus Osedax colonized and grew on cow bones deployed at depths ranging from 385 to 2893m in Monterey Bay, California. Colonization occurred as rapidly as two months following deployment of the cow bones, similar to the time it takes to colonize exposed whalebones. Some Osedax females found on the cow bones were producing eggs and some hosted dwarf males in their tubes. Morphological and molecular examinations of these worms confirmed the presence of six Osedax species, out of the eight species presently known from Monterey Bay. The ability of Osedax species to colonize, grow and reproduce on cow bones challenges previous notions that these worms are 'whale-fall specialists.'
Finger-like pattern formation in dilute surfactant pentaethylene glycol monododecyl ether solutions.
Kubo, Yoshihide; Yokoyama, Yasuhiro; Tanaka, Shinpei
2013-04-07
We report here peculiar finger-like patterns observed during the phase separation process of dilute micellar pentaethylene glycol monododecyl ether solutions. The patterns were composed of parallel and periodic threads of micelle-rich domains. Prior to this pattern formation, the phase separation always started with the appearance of water-rich domains rimmed by the micelle-rich domains. It was found that these rims played a significant role in the pattern formation. We explain this pattern formation using a simple simulation model with disconnectable springs. The simulation results suggested that the spatially inhomogeneous elasticity or connectivity of a transient gel of worm-like micelles was responsible for the rim formation. The rims thus formed lead rim-induced nucleation, growth, and elongation of the domains owing to their small mobility and the elastic frustration around them. These rim-induced processes eventually produce the observed finger-like patterns.
Yadav, Kunwar D; Tare, Vinod; Ahammed, M Mansoor
2011-06-01
The main objective of the present study was to determine the optimum stocking density for feed consumption rate, biomass growth and reproduction of earthworm Eisenia fetida as well as determining and characterising vermicompost quantity and product, respectively, during vermicomposting of source-separated human faeces. For this, a number of experiments spanning up to 3 months were conducted using soil and vermicompost as support materials. Stocking density in the range of 0.25-5.00 kg/m(2) was employed in different tests. The results showed that 0.40-0.45 kg-feed/kg-worm/day was the maximum feed consumption rate by E. fetida in human faeces. The optimum stocking densities were 3.00 kg/m(2) for bioconversion of human faeces to vermicompost, and 0.50 kg/m(2) for earthworm biomass growth and reproduction. Copyright © 2011 Elsevier Ltd. All rights reserved.
Luo, Lilan; Ando, Sayuri; Sasabe, Michiko; Machida, Chiyoko; Kurihara, Daisuke; Higashiyama, Tetsuya; Machida, Yasunori
2012-09-01
Leaf primordia with high division and developmental competencies are generated around the periphery of stem cells at the shoot apex. Arabidopsis ASYMMETRIC-LEAVES2 (AS2) protein plays a key role in the regulation of many genes responsible for flat symmetric leaf formation. The AS2 gene, expressed in leaf primordia, encodes a plant-specific nuclear protein containing an AS2/LOB domain with cysteine repeats (C-motif). AS2 proteins are present in speckles in and around the nucleoli, and in the nucleoplasm of some leaf epidermal cells. We used the tobacco cultured cell line BY-2 expressing the AS2-fused yellow fluorescent protein to examine subnuclear localization of AS2 in dividing cells. AS2 mainly localized to speckles (designated AS2 bodies) in cells undergoing mitosis and distributed in a pairwise manner during the separation of sets of daughter chromosomes. Few interphase cells contained AS2 bodies. Deletion analyses showed that a short stretch of the AS2 amino-terminal sequence and the C-motif play negative and positive roles, respectively, in localizing AS2 to the bodies. These results suggest that AS2 bodies function to properly distribute AS2 to daughter cells during cell division in leaf primordia; and this process is controlled at least partially by signals encoded by the AS2 sequence itself.
Leaf gas films contribute to rice (Oryza sativa) submergence tolerance during saline floods.
Herzog, Max; Konnerup, Dennis; Pedersen, Ole; Winkel, Anders; Colmer, Timothy David
2018-05-01
Floods and salinization of agricultural land adversely impact global rice production. We investigated whether gas films on leaves of submerged rice delay salt entry during saline submergence. Two-week-old plants with leaf gas films (+GF) or with gas films experimentally removed (-GF) were submerged in artificial floodwater with 0 or 50 mm NaCl for up to 16 d. Gas films were present >9 d on GF plants after which gas films were diminished. Tissue ion analysis (Na + , Cl - and K + ) showed that gas films caused some delay of Na + entry, as leaf Na + concentration was 36-42% higher in -GF leaves than +GF leaves on days 1-5. However, significant net uptakes of Na + and Cl - , and K + net loss, occurred despite the presence of gas films, indicating the likely presence of some leaf-to-floodwater contact, so that the gas layer must not have completely separated the leaf surfaces from the water. Natural loss and removal of gas films resulted in severe declines in growth, underwater photosynthesis, chlorophyll a and tissue porosity. Submergence was more detrimental to leaf P N and growth than the additional effect of 50 mm NaCl, as salt did not significantly affect underwater P N at 200 μm CO 2 nor growth. © 2016 John Wiley & Sons Ltd.
Foliage motion under wind, from leaf flutter to branch buffeting.
Tadrist, Loïc; Saudreau, Marc; Hémon, Pascal; Amandolese, Xavier; Marquier, André; Leclercq, Tristan; de Langre, Emmanuel
2018-05-01
The wind-induced motion of the foliage in a tree is an important phenomenon both for biological issues (photosynthesis, pathogens development or herbivory) and for more subtle effects such as on wi-fi transmission or animal communication. Such foliage motion results from a combination of the motion of the branches that support the leaves, and of the motion of the leaves relative to the branches. Individual leaf dynamics relative to the branch, and branch dynamics have usually been studied separately. Here, in an experimental study on a whole tree in a large-scale wind tunnel, we present the first empirical evidence that foliage motion is actually dominated by individual leaf flutter at low wind velocities, and by branch turbulence buffeting responses at higher velocities. The transition between the two regimes is related to a weak dependence of leaf flutter on wind velocity, while branch turbulent buffeting is strongly dependent on it. Quantitative comparisons with existing engineering-based models of leaf and branch motion confirm the prevalence of these two mechanisms. Simultaneous measurements of the wind-induced drag on the tree and of the light interception by the foliage show the role of an additional mechanism, reconfiguration, whereby leaves bend and overlap, limiting individual leaf flutter. We then discuss the consequences of these findings on the role of wind-mediated phenomena. © 2018 The Author(s).
Leaf Surface Effects on Retrieving Chlorophyll Content from Hyperspectral Remote Sensing
NASA Astrophysics Data System (ADS)
Qiu, Feng; Chen, JingMing; Ju, Weimin; Wang, Jun; Zhang, Qian
2017-04-01
Light reflected directly from the leaf surface without entering the surface layer is not influenced by leaf internal biochemical content. Leaf surface reflectance varies from leaf to leaf due to differences in the surface roughness features and is relatively more important in strong absorption spectral regions. Therefore it introduces dispersion of data points in the relationship between biochemical concentration and reflectance (especially in the visible region). Separation of surface from total leaf reflection is important to improve the link between leaf pigments content and remote sensing data. This study aims to estimate leaf surface reflectance from hyperspectral remote sensing data and retrieve chlorophyll content by inverting a modified PROSPECT model. Considering leaf surface reflectance is almost the same in the visible and near infrared spectral regions, a surface layer with a reflectance independent of wavelength but varying from leaf to leaf was added to the PROSPECT model. The specific absorption coefficients of pigments were recalibrated. Then the modified model was inverted on independent datasets to check the performance of the model in predicting the chlorophyll content. Results show that differences in estimated surface layer reflectance of various species are noticeable. Surface reflectance of leaves with epicuticular waxes and trichomes is usually higher than other samples. Reconstruction of leaf reflectance and transmittance in the 400-1000 nm wavelength region using the modified PROSPECT model is excellent with low root mean square error (RMSE) and bias. Improvements for samples with high surface reflectance (e.g. maize) are significant, especially for high pigment leaves. Moreover, chlorophyll retrieved from inversion of the modified model is consequently improved (RMSE from 5.9-13.3 ug/cm2 with mean value 8.1 ug/cm2, while mean correlation coefficient is 0.90) compared to results of PROSPECT-5 (RMSE from 9.6-20.2 ug/cm2 with mean value 13.1 ug/cm2, while mean correlation coefficient is 0.81). Underestimation of high chlorophyll content, which is due to underestimation of reflectance in the visible region of PROSPECT, is partially corrected or alleviated. Improvements are particularly noticeable for leaves with high surface reflectance or high chlorophyll content, which both lead to large proportions of surface reflectance to the total leaf reflectance.
NASA Astrophysics Data System (ADS)
Crow, S. E.; Filley, T.; Conyers, G.; Stott, D.; McCormick, M.; Whigham, D.; Taylor, D.
2006-12-01
Changes in vegetation structure are expected in forests globally under predicted future climate scenarios. Shifts in type or quantity of litter inputs, which will be associated with changes in plant community, may influence soil organic matter (SOM) characteristics. We altered litter inputs in a mixed-deciduous forest at the Smithsonian Environmental Research Center beginning in May 2004: litter removal, leaf amendment, and wood amendment plots were established in three old (120-150 y) and three young (50-70 y) forests. Plots were amended with wood and leaves collected locally from the dominant tree species, tulip poplar (Lirodendron tulipifera). 0-5 cm A horizon soil was collected in November 2005, 18 months after initial treatment, and physically fractionated first by dispersal in HMP and size separation (53 μm) to remove silts and clays then the >53 μm fraction by density (1.4 g cm-3) in SPT to separate the organic debris (light fraction, LF) from the mineral material. Soil with the greatest amount of C present within the LF came from the wood amendment treatment (35.2 ± 0.1%), followed by the leaf amendment (27.7 ± 0.0%) and the litter removal (24.5 ± 0.0%) treatments. In a pattern opposite of the other treatments, leaf amended soil from the old sites had less C within LF than the young. Potentially, a priming effect from the leaf addition at the old sites resulted in increased decomposition of soil LF. While at the young sites, invasive earthworms potentially provided a rapid, direct mode for incorporation of fresh leaf inputs into LF. Preliminary data indicate differences in lignin and cutin/suberin decay rates during litter decomposition between old and young sites. An investigation into the biopolymer composition of LF will determine whether altering litter inputs will ultimately influence SOM dynamics at both the old and young forest sites.
McBriarty, G J; Kidd, K A; Burridge, L E
2018-05-01
The polychaete Nereis virens occurs commonly in marine sediments, is widely distributed, and is a popular bait species, as well as a potential replacement for wild-caught fish in commercial fish feed preparations. It is being considered as a potential co-extractive species for culture in integrated multi-trophic aquaculture operations. However, it is not known whether pesticides or drugs used to treat sea lice on farmed salmon, such as emamectin benzoate (EB), would adversely affect cultured or wild worms, because these compounds may persist in the environment. To determine the potential effects of EB to N. virens, bioassays were performed wherein worms were exposed in sand for 30 days to a concentration of 400 µg/kg dw (nominal). While no treatment-related mortality occurred, significant decreases in worm mass and marked behavioral changes (lack of burrowing) were observed in EB-treated sand compared with controls. These lab-based observations suggest a potential hazard to worms at sites where EB treatments have occurred.
Worm-like micelles of CTAB and sodium salicylate under turbulent flow.
Rodrigues, Roberta K; da Silva, Marcelo A; Sabadini, Edvaldo
2008-12-16
Polymers with high molecular weight and worm-like micelles are drag-reducing agents under turbulent flow. However, in contrast to the polymeric systems, the worm-like micelles do not undergo mechanical degradation due to the turbulence, because their macromolecular structure can be spontaneously restored. This very favorable property, together with their drag-reduction capability, offer the possibility to use such worm-like micelles in heating and cooling systems to recirculate water while expending less energy. The formation, growth, and stability of worm-like micelles formed by cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal) were investigated using the self-fluorescence of salicylate ions and the ability of the giant micelles to promote hydrodynamic drag reduction under turbulent flow. The turbulence in solutions of CTAB-Sal was produced within the double-gap cell of a rotational rheometer. Detailed diagrams were obtained for different ratios of Sal and CTAB, which revealed transitions associated with the thermal stability of giant micelles under turbulent flow.
Dracunculiasis (guinea worm disease) in the Bume (Nyangaton) people of South Omo, Ethiopia.
Jemaneh, L; Taticheff, S
1993-07-01
A village-to-village search for active dracunculiasis cases was carried out in an endemic area of the Bume (Nyangaton) tribe of South Omo Region, Ethiopia. A total of 21 cases, of which 6, 5, and 10 had pre-emergent, emergent and complicated Guinea worm disease, respectively, were identified. Twenty-two worms, ranging from 1-3 per patient, were removed mainly from the lower limbs; worm appearance seems to be associated more with the right limb. Adults between the ages of 20-30 years are highly affected and infection appears to be sex-related as 14/21 (66.7%) of the cases are females. Water procured from water-holes drug in dry river beds provides an ideal situation for the transmission of dracunculiasis amongst the tribesmen. The knowledge, attitudes and perceptions of the Bume people towards the disease and the public health significance of dracunculiasis are discussed in relation to the current goal of the national and global Guinea worm eradication programme.
Zain, Mariani Mohd; Yahaya, Zary Shariman; Him, Nik Ahmad Irwan Izzauddin Nik
2016-01-01
To date, the ivermectin resistance in nematode parasites has been reported and many studies are carried out to determine the causes of this problem. A free-living Caenorhabditis elegans is used as a model system for this study to investigate the response of C. elegans to ivermectin exposure by using larval development assay. Worms were exposed to ivermectin at concentration from 1 ng/mL to 10 ng/mL and dimethyl sulphoxide (DMSO) as a control. The developments of the worms were monitored for 24, 48, 72, and 96 hours until the worms become adults. Results indicated that worms’ growth began to be affected by ivermectin at a concentration of 5 ng/mL, while at the concentration of 6, 7, 8, 9, and 10 ng/mL, the growth of worms were inhibited compared to control worms. Further study of the protein expression in C. elegans should be done to investigate the up-regulated and down-regulated proteins involve in ivermectin resistance. PMID:27965734
Quantifiers more or less quantify online: ERP evidence for partial incremental interpretation
Urbach, Thomas P.; Kutas, Marta
2010-01-01
Event-related brain potentials were recorded during RSVP reading to test the hypothesis that quantifier expressions are incrementally interpreted fully and immediately. In sentences tapping general knowledge (Farmers grow crops/worms as their primary source of income), Experiment 1 found larger N400s for atypical (worms) than typical objects (crops). Experiment 2 crossed object typicality with non-logical subject-noun phrase quantifiers (most, few). Off-line plausibility ratings exhibited the crossover interaction predicted by full quantifier interpretation: Most farmers grow crops and Few farmers grow worms were rated more plausible than Most farmers grow worms and Few farmers grow crops. Object N400s, although modulated in the expected direction, did not reverse. Experiment 3 replicated these findings with adverbial quantifiers (Farmers often/rarely grow crops/worms). Interpretation of quantifier expressions thus is neither fully immediate nor fully delayed. Furthermore, object atypicality was associated with a frontal slow positivity in few-type/rarely quantifier contexts, suggesting systematic processing differences among quantifier types. PMID:20640044
Tian, Yu; Li, Zhipeng; Lu, Yaobin
2012-10-01
The study focused on the membrane fouling mitigation observed in a membrane bioreactor (MBR) coupled with worm reactor system. During the operation time of 100 days, the transmembrane pressure (TMP) in the combined system was maintained less than 5 kPa, while the final TMP in the Control-MBR increased to 30 kPa. The changes in properties of soluble microbial products (SMP) and extracellular polymeric substances (EPS) after worm predation were investigated by means of various analytical techniques. It was found that due to the worm predation, the reduced amount of EPS was far more than the increased amount of SMP leading to a significant decrease of protein-like substances which were dominant in the membrane foulants. Except for the content decrease, worm predation destroyed the functional groups of simple aromatic proteins and tryptophan protein-like substances in EPS, making them have lower tendency attaching to the membrane in the combined system. Copyright © 2012 Elsevier Ltd. All rights reserved.
Worms Expelled With the Urine From a Bosniak Cyst III of the Left Kidney.
Yang, Jie; Li, Pu; Su, Chuan; Zhang, Jia-Yi; Gu, Min
2016-07-01
An old fishman presented with left lumbago and finding worms in his urine. Type-B ultrasonic inspection and computed tomography scan found a Bosniak cyst III, containing several wire-like elements, in the middle of the left kidney. Expelled worms were confirmed to be Dioctophyma renale. After two courses of albendazole, the man was cured. Copyright © 2016 Elsevier Inc. All rights reserved.
Khabirova, Eleonora; Moloney, Aileen; Marciniak, Stefan J; Williams, Julie; Lomas, David A; Oliver, Stephen G; Favrin, Giorgio; Sattelle, David B; Crowther, Damian C
2014-01-01
The human Aβ peptide causes progressive paralysis when expressed in the muscles of the nematode worm, C. elegans. We have exploited this model of Aβ toxicity by carrying out an RNAi screen to identify genes whose reduced expression modifies the severity of this locomotor phenotype. Our initial finding was that none of the human orthologues of these worm genes is identical with the genome-wide significant GWAS genes reported to date (the "white zone"); moreover there was no identity between worm screen hits and the longer list of GWAS genes which included those with borderline levels of significance (the "grey zone"). This indicates that Aβ toxicity should not be considered as equivalent to sporadic AD. To increase the sensitivity of our analysis, we then considered the physical interactors (+1 interactome) of the products of the genes in both the worm and the white+grey zone lists. When we consider these worm and GWAS gene lists we find that 4 of the 60 worm genes have a +1 interactome overlap that is larger than expected by chance. Two of these genes form a chaperonin complex, the third is closely associated with this complex and the fourth gene codes for actin, the major substrate of the same chaperonin.
Growth and development of Gymnophalloides seoi in immunocompetent and immunosuppressed C3H/HeN mice
Chung, Won-Jae; Kook, Jina; Seo, Min; Park, Yun-Kyu; Guk, Sang-Mee; Choi, Min-Ho; Lee, Soon-Hyung
1999-01-01
The growth and development of Gymnophalloides seoi were studied in C3H/HeN mice and effects of immunosuppression of the host on the worm development were observed. Two hundred metacercariae of G. seoi were orally administered to each mouse, and worms were recovered on days 1, 3, 5, 7, 14 and 21 post-infection (PI). The worm recovery rate was significantly higher in immunosuppressed (ImSP) mice than in immunocompetent (ImCT) mice except on days 1 and 3 PI. The worms attained sexual maturity by day 3 PI with eggs in the uterus, and worm dimensions and the number of uterine eggs continuously increased until day 14 PI in ImSP mice. Worms recovered from ImSP mice were significantly larger in size than those from ImCT mice on days 1 and 3 PI, and the number of uterine eggs was significantly larger in ImSP mice on days 5 and 7 PI. Genital organs such as the ovary, testes, and vitellaria, that were already developed in the metacercarial stage, grew a little in size until day 14 PI. The results show that the C3H/HeN mouse is, though not excellent, a suitable laboratory host for G. seoi. PMID:10188379
Maghraby, Amany Sayed; Hamed, Manal Abdel-Aziz; Ali, Sanaa Ahmed
2010-06-03
In this study, we evaluated the biochemical, immunological, histopathological and antischistosomal activities of Schistosoma mansoni or Fasciola gigantica worm homogenates mixed either with or without saponin that was extracted from Atriplex nummularia. The immunization schedule was based on subcutaneous administration of two doses (50 microg /100 microl PBS) of each homogenate with time intervals of 15 days. After 15 days of the last homogenate inoculation, all mice were challenged with 100 Schistosoma mansoni cercariae and sacrificed after two months. Free radical scavengers and liver function enzymes were determined in mice liver. Worm counting and the histopathological picture of the liver were also done. Immunization with Schistosoma or Fasciola worm homogenates, mixed either with or without saponin, recorded an amelioration of the free radical scavenger levels, liver function enzymes and reduction in worm burden, as well as improvement of the histological feature of the liver, the number and size of granuloma, evidence of increased immune reaction manifested by a lymphocytic cuff surrounding the granuloma, diminution of its fibrotic and collagen content, and destruction of Schistosoma ova. Fasciola or Schistosoma worm antigens mixed with or without saponin succeeded to eliminate the product of oxidative stress and assistance in immune-mediated destruction of eggs that ameliorate the histopathological picture of the liver cells and preserve its function.
Lu, Fong-Mei; Stewart, James; White, John G.
2007-01-01
The utilization of biology research resources, coupled with a “learning by inquiry” approach, has great potential to aid students in gaining an understanding of fundamental biological principles. To help realize this potential, we have developed a Web portal for undergraduate biology education, WormClassroom.org, based on current research resources of a model research organism, Caenorhabditis elegans. This portal is intended to serve as a resource gateway for students to learn biological concepts using C. elegans research material. The driving forces behind the WormClassroom website were the strengths of C. elegans as a teaching organism, getting researchers and educators to work together to develop instructional materials, and the 3 P's (problem posing, problem solving, and peer persuasion) approach for inquiry learning. Iterative assessment is an important aspect of the WormClassroom site development because it not only ensures that content is up-to-date and accurate, but also verifies that it does, in fact, aid student learning. A primary assessment was performed to refine the WormClassroom website utilizing undergraduate biology students and nonstudent experts such as C. elegans researchers; results and comments were used for site improvement. We are actively encouraging continued resource contributions from the C. elegans research and education community for the further development of WormClassroom. PMID:17548872
Gastrointestinal nematode infections in sheep raised in Botucatu, state of São Paulo, Brazil.
Wilmsen, Maurício Orlando; Silva, Bruna Fernanda; Bassetto, César Cristiano; Amarante, Alessandro Francisco Talamini do
2014-01-01
Gastrointestinal nematode infections were evaluated in sheep raised in Botucatu, state of São Paulo, Brazil between April 2008 and March 2011. Every month, two tracer lambs grazing with a flock of sheep were exposed to natural infection with gastrointestinal nematodes for 28 consecutive days. At the end of this period, the lambs were sacrificed for worm counts. Haemonchus contortus presented 100% of prevalence. The seasons exerted no significant influence on the mean intensity of H. contortus, which ranged from 315 worms in November 2010 to 2,5205 worms in January 2011. The prevalence of Trichostrongylus colubriformis was also 100%, with the lowest mean intensity (15 worms) recorded in February 2011 and the highest (9,760 worms) in October 2009. In the case of T. colubriformis, a significant correlation coefficient was found between worm counts vs. rainfall (r = -0.32; P <0.05). Three other nematodes species were found in tracer lambs, albeit in small numbers. Their prevalence and mean intensity (in parenthesis) were as follows: Oesophagostomum columbianum 28% (25.2), Cooperia curticei 7% (4.5) and Trichuris spp. 2% (1). In conclusion, the environmental conditions of the area proved to be highly favorable for the year-round transmission of H. contortus and T. colubriformis.
Procyanidins from apples (Malus pumila Mill.) extend the lifespan of Caenorhabditis elegans.
Sunagawa, Tadahiro; Shimizu, Takahiko; Kanda, Tomomasa; Tagashira, Motoyuki; Sami, Manabu; Shirasawa, Takuji
2011-01-01
Apple polyphenols (AP) mainly consist of procyanidins (PC), which are composed of (-)-epicatechins and (+)-catechins. In order to investigate the antiageing effects of PC, we measured the lifespan of CAENORHABDITIS ELEGANS worms treated with PC. Treatment with 65 µg/mL PC extended the mean lifespan of wild-type N2 and FEM-1 worms by 12.1 % and 8.4 %, respectively, i.e., to a similar extent as resveratrol. In addition, treatment with 100 µg/mL AP also significantly prolonged the mean lifespan of the same worms by 12.0 % and 5.3 %, respectively, i.e., to a similar extent as PC. In contrast, treatment with (-)-epicatechin did not extend the lifespan of the worms. PC did not modify the growth, food intake, or fecundity of C. elegans. Treatment with PC did not extend the lifespan of MEV-1 worms, which show excessive oxidative stress, indicating that PC had no antioxidant ability in the MEV-1 mutant. Moreover, treatment with PC had no effect on the longevity of SIR-2.1 worms, which lack the activity of SIR-2, a member of the sirtuin family of NAD (+)-dependent protein deacetylases. These results indicated that PC has SIR-2.1-dependent antiageing effects on C. elegans. © Georg Thieme Verlag KG Stuttgart · New York.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsue, S.Y.; Hsue, H.F.; Osborne, J.W.
1982-04-01
A high degree of immunity, as shown by a 91% reduction of the number of worms recovered was found in five groups of mice that were immunized five times with highly X-irradiated cercariae and then challenged with 10, 20, 50, 100, or 500 normal Schistosoma mansoni cercariae. The results indicated that there were no significant differences in worm reduction in immunized mice challenged with different numbers of cercariae; consequently the immunity induced by this immunization method did not appear to be challenge-dose-dependent. However, the results also showed that when immunized mice were challenged with 500, 100, 50, 20, and 10more » cercariae, 0, 13, 26, 56, and 68%, respectively, of the experimental animals were free of worms. Thus, the percentage of worm-negative cases increased as the number of challenge cercariae decreased. When viewed in this manner, the acquired immunity may be considered challenge-dose-dependent as well. If this method of vaccination is used for schistosomiasis control, we may anticipate that in both hypo- and hyperendemic areas, the intensity of infection and the severity of the disease will be reduced owing to a reduction in worms burdens, and in hypoendemic areas, there will be a number of worm-free cases.« less
Stocking Density Optimization for Enhanced Bioconversion of Fly Ash Enriched Vermicompost.
Mupambwa, Hupenyu A; Mnkeni, Pearson N S
2016-05-01
Although it is widely agreed that stocking density critically affects the rate of vermicomposting, there is no established stocking density for mixtures of fly ash and other waste materials. This study sought to optimize (Savigny, 1826) stocking density for effective biodegradation and nutrient release in a fly ash-cow dung-waste paper (FCP) mixture. Four stocking densities of 0, 12.5, 25, and 37.5 g worms kg were evaluated. Although the 12.5, 25, and 37.5 g worms kg treatments all resulted in a mature vermicompost, stocking densities of 25 and 37.5 g worms kg resulted in faster maturity, higher humification parameters, and a significantly lower final C/N ratio (range 11.1-10.4). The activity of β-glucosidase and fluorescein diacetate hydrolysis enzymes showed faster stabilization at stocking densities of 25 and 37.5 g worms kg, indicating compost stability and maturity. Similarly, a stocking density of 25 g worms kg resulted in the highest release of Olsen-extractable P and (NO + NO)-N contents. The 0-, 12.5-, 25-, and 37.5-g treatments resulted in net Olsen P increases of 16.3, 38.9, 61.0, and 53.0%, respectively, after 10 wk. Although compost maturity could be attained at stocking densities of 12.5 g worms kg, for faster production of humified and nutrient-rich FCP vermicompost, a stocking density of 25 g worms kg seems most appropriate. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Fujimaki, Y; Kamachi, T; Yanagi, T; Cáceres, A; Maki, J; Aoki, Y
2005-03-01
Twelve extracts of 11 Guatemalan medicinal plants were initially screened in vitro for potential macrofilaricidal activity against Brugia pahangi, a lymphatic dwelling filarial worm, using concentrations from 125 to 1000 microg ml(-1) of each extract that could be dissolved in the culture medium. Of 12 extracts used, the ethanol extract of leaves of Neurolaena lobata showed the strongest activity against the motility of adult worms. Subsequently, the extract of N. lobata was extensively examined in vitro for macro- and micro-filaricidal effects using a series of concentrations of 500, 250, 100, 50 and 10 microg ml(-1). The effects were assessed by worm motility, microfilarial release by female worms and a MTT assay. The effect on the motility of adult worms was observed in a concentration- and time-dependent manner. The time required to stop motility of both sexes of adult worms was 6 h at 500 microg ml(-1), 24 h at 250 microg ml(-1), and 3 days for females and 4 days for males at 100 microg ml(-1). The movement of females ceased at 4 days at a concentration of 50 microg ml(-1) whereas the motility of males was only reduced. The loss of worm's viability was confirmed by the MTT assay and was similar to the motility results. These concentrations, including 10 microg ml(-1), prevented microfilarial release by females in a concentration- and time-dependent manner. Concentrations higher than 100 microg ml(-1) even induced mortality of the microfilariae. The present study suggested that the ethanol extract of Neurolaena lobata has potential macro- and micro-filaricidal activities.
A microfluidic device for automated, high-speed microinjection of Caenorhabditis elegans
Song, Pengfei; Dong, Xianke; Liu, Xinyu
2016-01-01
The nematode worm Caenorhabditis elegans has been widely used as a model organism in biological studies because of its short and prolific life cycle, relatively simple body structure, significant genetic overlap with human, and facile/inexpensive cultivation. Microinjection, as an established and versatile tool for delivering liquid substances into cellular/organismal objects, plays an important role in C. elegans research. However, the conventional manual procedure of C. elegans microinjection is labor-intensive and time-consuming and thus hinders large-scale C. elegans studies involving microinjection of a large number of C. elegans on a daily basis. In this paper, we report a novel microfluidic device that enables, for the first time, fully automated, high-speed microinjection of C. elegans. The device is automatically regulated by on-chip pneumatic valves and allows rapid loading, immobilization, injection, and downstream sorting of single C. elegans. For demonstration, we performed microinjection experiments on 200 C. elegans worms and demonstrated an average injection speed of 6.6 worm/min (average worm handling time: 9.45 s/worm) and a success rate of 77.5% (post-sorting success rate: 100%), both much higher than the performance of manual operation (speed: 1 worm/4 min and success rate: 30%). We conducted typical viability tests on the injected C. elegans and confirmed that the automated injection system does not impose significant adverse effect on the physiological condition of the injected C. elegans. We believe that the developed microfluidic device holds great potential to become a useful tool for facilitating high-throughput, large-scale worm biology research. PMID:26958099
Bouchet, Philippe; Boxshall, Geoff; Fauchald, Kristian; Gordon, Dennis; Hoeksema, Bert W.; Poore, Gary C. B.; van Soest, Rob W. M.; Stöhr, Sabine; Walter, T. Chad; Vanhoorne, Bart; Decock, Wim
2013-01-01
The World Register of Marine Species is an over 90% complete open-access inventory of all marine species names. Here we illustrate the scale of the problems with species names, synonyms, and their classification, and describe how WoRMS publishes online quality assured information on marine species. Within WoRMS, over 100 global, 12 regional and 4 thematic species databases are integrated with a common taxonomy. Over 240 editors from 133 institutions and 31 countries manage the content. To avoid duplication of effort, content is exchanged with 10 external databases. At present WoRMS contains 460,000 taxonomic names (from Kingdom to subspecies), 368,000 species level combinations of which 215,000 are currently accepted marine species names, and 26,000 related but non-marine species. Associated information includes 150,000 literature sources, 20,000 images, and locations of 44,000 specimens. Usage has grown linearly since its launch in 2007, with about 600,000 unique visitors to the website in 2011, and at least 90 organisations from 12 countries using WoRMS for their data management. By providing easy access to expert-validated content, WoRMS improves quality control in the use of species names, with consequent benefits to taxonomy, ecology, conservation and marine biodiversity research and management. The service manages information on species names that would otherwise be overly costly for individuals, and thus minimises errors in the application of nomenclature standards. WoRMS' content is expanding to include host-parasite relationships, additional literature sources, locations of specimens, images, distribution range, ecological, and biological data. Species are being categorised as introduced (alien, invasive), of conservation importance, and on other attributes. These developments have a multiplier effect on its potential as a resource for biodiversity research and management. As a consequence of WoRMS, we are witnessing improved communication within the scientific community, and anticipate increased taxonomic efficiency and quality control in marine biodiversity research and management. PMID:23505408
AN ORIENTATIONAL RESPONSE TO WEAK GAMMA RADIATION
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, F.A. Jr.
1963-10-01
The common planarian worm, Duesia dorotocephsla, displays a significant orientational response to increase in Cs/sup 137/ gamma radiation when the increase is no greater than six times background. The worms are able to distinguish the direction of the weak gamma source, turning away from it, whether it is presented on the right or left side. The response sign is, therefore, the same as that of the response of these negatively phototactic worms to visible light. There is a clear compass-directional relationship of the responsiveness to the experimental gamma radiation. A conspicuous negative response is present when the worms are travelingmore » northward or southward in the earth's field with the gamma change in an east-west axis. No statistically significant mean turning response to the gamma radiation is found when the worms are traveling eastward or westward in the earth's field with the gamma change in a north-south axis. The previously observed annual fluctuation in the character of the monthly orientational rhythm of north-directed worms has been confirmed in an additional year of study. During colder months, the rhythm is monthly; during warmer months it is semi-monthly. There is a semi-monthly fluctuation in the response of Dugesia to weak gamma radiation during mid-morning hours, the worms turning away from the source for four days prior to new end full moon, and toward it for two days following new and full moon. The stronger the field strength, up to 9 times backgound, the larger the amplitude of the rhythm. There is a direct relationship between intensities of gamma radiation between that of background and nine times backgound, and the strength of the negative response of the worms. Evidence suggests that the negative response of Dugesia to a gamma source may be modified by experimental alteration of the natural ambient electrostatic field. Some possible biological significances of this remarkable responsiveness to gamma radiation, and its particular properties, are discussed briefly. (auth)« less
Wang, Sijie Jason; Wang, Zhao-Wen
2013-01-01
A major challenge of neuroscience is to understand the circuit and gene bases of behavior. C. elegans is commonly used as a model system to investigate how various gene products function at specific tissue, cellular, and synaptic foci to produce complicated locomotory and bending behavior. The investigation generally requires quantitative behavioral analyses using an automated single-worm tracker, which constantly records and analyzes the position and body shape of a freely moving worm at a high magnification. Many single-worm trackers have been developed to meet lab-specific needs, but none has been widely implemented for various reasons, such as hardware difficult to assemble, and software lacking sufficient functionality, having closed source code, or using a programming language that is not broadly accessible. The lack of a versatile system convenient for wide implementation makes data comparisons difficult and compels other labs to develop new worm trackers. Here we describe Track-A-Worm, a system rich in functionality, open in source code, and easy to use. The system includes plug-and-play hardware (a stereomicroscope, a digital camera and a motorized stage), custom software written to run with Matlab in Windows 7, and a detailed user manual. Grayscale images are automatically converted to binary images followed by head identification and placement of 13 markers along a deduced spline. The software can extract and quantify a variety of parameters, including distance traveled, average speed, distance/time/speed of forward and backward locomotion, frequency and amplitude of dominant bends, overall bending activities measured as root mean square, and sum of all bends. It also plots worm travel path, bend trace, and bend frequency spectrum. All functionality is performed through graphical user interfaces and data is exported to clearly-annotated and documented Excel files. These features make Track-A-Worm a good candidate for implementation in other labs. PMID:23922769
Hu, Chun-Chih; Wu, Gong-Her; Hua, Tzu-En; Wagner, Oliver I; Yen, Ta-Jen
2018-03-14
We employ model organism Caenorhabditis elegans to effectively study the toxicology of anatase and rutile phase titanium dioxide (TiO 2 ) nanoparticles (NPs). The experimental results show that nematode C. elegans can take up fluorescein isothiocyanate-labeled TiO 2 NPs and that both anatase and rutile TiO 2 NPs can be detected in the cytoplasm of cultured primary neurons imaged by transmission electron microscopy. After TiO 2 NP exposure, these neurons also grow shorter axons, which may be related to the detected impeded worm locomotion behavior. Furthermore, anatase TiO 2 NPs did not affect the worm's body length; however, we determined that a concentration of 500 μg/mL of anatase TiO 2 NPs reduced the worm population by 50% within 72 h. Notably, rutile TiO 2 NPs negatively affect both the body size and worm population. Worms unable to enter the L4 larval stage explain a severe reduction in the worm population at TiO 2 NPs LC 50 /3d. To obtain a better understanding of the cellular mechanisms involved in TiO 2 NP intoxication, DNA microarray assays were employed to determine changes in gene expression in the presence or absence of TiO 2 NP exposure. Our data reveal that three genes (with significant changes in expression levels) were related to metal binding or metal detoxification (mtl-2, C45B2.2, and nhr-247), six genes were involved in fertility and reproduction (mtl-2, F26F2.3, ZK970.7, clec-70, K08C9.7, and C38C3.7), four genes were involved in worm growth and body morphogenesis (mtl-2, F26F2.3, C38C3.7, and nhr-247), and five genes were involved in neuronal function (C41G6.13, C45B2.2, srr-6, K08C9.7, and C38C3.7).
Costello, Mark J; Bouchet, Philippe; Boxshall, Geoff; Fauchald, Kristian; Gordon, Dennis; Hoeksema, Bert W; Poore, Gary C B; van Soest, Rob W M; Stöhr, Sabine; Walter, T Chad; Vanhoorne, Bart; Decock, Wim; Appeltans, Ward
2013-01-01
The World Register of Marine Species is an over 90% complete open-access inventory of all marine species names. Here we illustrate the scale of the problems with species names, synonyms, and their classification, and describe how WoRMS publishes online quality assured information on marine species. Within WoRMS, over 100 global, 12 regional and 4 thematic species databases are integrated with a common taxonomy. Over 240 editors from 133 institutions and 31 countries manage the content. To avoid duplication of effort, content is exchanged with 10 external databases. At present WoRMS contains 460,000 taxonomic names (from Kingdom to subspecies), 368,000 species level combinations of which 215,000 are currently accepted marine species names, and 26,000 related but non-marine species. Associated information includes 150,000 literature sources, 20,000 images, and locations of 44,000 specimens. Usage has grown linearly since its launch in 2007, with about 600,000 unique visitors to the website in 2011, and at least 90 organisations from 12 countries using WoRMS for their data management. By providing easy access to expert-validated content, WoRMS improves quality control in the use of species names, with consequent benefits to taxonomy, ecology, conservation and marine biodiversity research and management. The service manages information on species names that would otherwise be overly costly for individuals, and thus minimises errors in the application of nomenclature standards. WoRMS' content is expanding to include host-parasite relationships, additional literature sources, locations of specimens, images, distribution range, ecological, and biological data. Species are being categorised as introduced (alien, invasive), of conservation importance, and on other attributes. These developments have a multiplier effect on its potential as a resource for biodiversity research and management. As a consequence of WoRMS, we are witnessing improved communication within the scientific community, and anticipate increased taxonomic efficiency and quality control in marine biodiversity research and management.
Eysker, M; Bakker, N; Kooyman, F N J; Olthuis, S Olde; Ploeger, H W
2006-09-10
In 2004, an experiment was carried out to evaluate the effect of biological control through feeding spores of Duddingtonia flagrans on parasitic gastroenteritis in lambs, kept under an evasive grazing system. In total 66 lambs were used. Forty naturally infected 3-month old ram lambs were weaned in mid June, and divided into four groups of 10 lambs. On 21 June, G1-G4 were moved to four separate virtually clean plots, they were moved after 4 and 8 weeks to similar plots, and housed after 12 weeks to be necropsied 16 days later. The other 26 lambs had been raised helminth-free, and were used as pairs of tracer lambs. All but one of these pairs, were grazed during the last 2 weeks on each plot. The remaining pair (TA) was grazed during the last 2 weeks on pasture (30 August to 13 September) on the plot that had been grazed by G3 between 19 July and 16 August, to study inhibited development in Haemonchus contortus. All lambs were fed 200 g of concentrates daily throughout the whole period, and those of G1 and G2 were also fed 500,000 spores of D. flagrans/kg bodyweight daily. The faecal cultures demonstrated a high reduction in yield as a result of fungal application. However, no differences between groups were seen in weight gain, faecal egg counts, pasture larval counts, worm counts and tracer worm counts. H. contortus was the dominant species, and it is obvious that the moves at 4-week intervals prevented the development of severe haemonchosis. This is in particular demonstrated by the much higher worm counts in the two TA tracer lambs grazed. Nevertheless, increases to high faecal egg counts 3 weeks after the first and second moves, indicated acquisition of infection before these moves and at least subclinical haemonchosis. This was supported with the worm counts of lambs and tracer lambs. A higher proportion of inhibited early L4 than in other tracers and than in the permanent lambs were found in the pair of TA tracer lambs. This indicates that moves to new pastures in late summer and autumn delays the onset of inhibition.
Ganeshan, Seedhabadee; Sharma, Pallavi; Young, Lester; Kumar, Ashwani; Fowler, D Brian; Chibbar, Ravindra N
2011-03-01
Low-temperature (LT) tolerance in winter wheat (Triticum aestivum L.) is an economically important but complex trait. Four selected wheat genotypes, a winter hardy cultivar, Norstar, a tender spring cultivar, Manitou and two near-isogenic lines with Vrn-A1 (spring Norstar) and vrn-A1 (winter Manitou) alleles of Manitou and Norstar were cold-acclimated at 6°C and crown and leaf tissues were collected at 0, 2, 14, 21, 35, 42, 56 and 70 days of cold acclimation. cDNA-AFLP profiling was used to determine temporal expression profiles of transcripts during cold-acclimation in crown and leaf tissues, separately to determine if LT regulatory circuitries in crown and leaf tissues could be delineated using this approach. Screening 64 primer combinations identified 4,074 and 2,757 differentially expressed transcript-derived fragments (TDFs) out of which 38 and 16% were up-regulated as compared to 3 and 6% that were down-regulated in crown and leaf tissues, respectively. DNA sequencing of TDFs revealed sequences common to both tissues including genes coding for DEAD-box RNA helicase, choline-phosphate cytidylyltransferase and delta-1-pyrroline carboxylate synthetase. TDF specific to crown tissues included genes coding for phospahtidylinositol kinase, auxin response factor protein and brassinosteroid insensitive 1-associated receptor kinase. In leaf, genes such as methylene tetrahydrofolate reductase, NADH-cytochrome b5 reductase and malate dehydrogenase were identified. However, 30 and 14% of the DNA sequences from the crown and leaf tissues, respectively, were hypothetical or unknown proteins. Cluster analysis of up-, down-regulated and unique TDFs, DNA sequence and real-time PCR validation, infer that mechanisms operating in crown and leaf tissue in response to LT are differently regulated and warrant further studies.
Mathews, Miya Gugulethu; Ajayi, Oyemitan Idris; Opeoluwa, Oyedeji Oyehan; Oluwatobi, Oluwafemi Samuel; Benedicta N, Nkeh-Chungag; Phindile, Songca Sandile; Oyedeji; Omowumi, Adebola
2016-01-01
Background: Pentanisia prunelloides is a medicinal plant widely used to remedy various ailments including infections, fever and rheumatism in Eastern Cape Province of South Africa. There is scanty report on the phytochemical and biological properties of the plant; hence various solvent extracts of the dried plant materials were phytochemically screened, and its aqueous extract evaluated for acute toxicity effect, analgesic and antiinflammatory properties in rodents. Methods and Materials: Different extracts of both leaf and rhizome were obtained separately with ethanol, methanol and water. Portions of the filtrate were used for qualitative screening of secondary metabolites and remaining portions were concentrated and dried. Dried grounded leaf and rhizome of the plant were also used for quantitative screening for some major components. The aqueous extract of the leaf and rhizome were used for acute toxicity (LD50) test, antiinflammatory and analgesic activities in rodents. Results: The qualitative phytochemical screening showed the presence of several phytoconstituents with saponins, flavonoids and alkaloids constituting highest constituents in the leaf and rhizome. The LD50: of the aqueous extracts (from leaf or rhizome) was found to be ≥5000 mg/kg orally. The leaf and rhizome aqueous extract (250-500 mg/kg) significantly (p<0.01) reduced egg albumin-induced paw oedema and paw licking in mice induced by formalin, signifying antinociceptive and antiinflammatory activities respectively. Conclusion: It is concluded that the leaf and rhizome of P. prunelloides are rich in various phytochemicals which could be associated with their medicinal uses. The aqueous leaf and rhizome extracts are similarly non-toxic orally, showed antiinflammatory and analgesic potentials thus rationalizing its use in folkloric medicine. PMID:28480377
Remote sensing and the optical properties of the narrow cylindrical leaves of Juncus roemerianus
Ramsey, Elijah W.; Rangoonwala, A.
2004-01-01
To develop a more complete foundation for remote sensing of the marsh grass Juncus roemerianus, we measured the optical properties of its cylindrical leaves at sites of different canopy height, biomass composition and amount, and connectivity to ocean flushing. To measure the leaf optical properties, we adapted a technique used for conifer needles. After establishing the reliability and limits of the adapted technique to the wider J.roemerianus leaves, mean transmittance and reflectance spectra were compared to associated leaf diameters from two dates in 1999 and 2002 and at each site. Transmittance was inversely related to leaf diameter. Mean transmittance and reflectance generated from reoccupation of many field sites in 2002 indicated little or no difference in transmittance between years, a slight reflectance difference in the visible (<2%) and a slightly higher reflectance difference in the near infrared (NIR) (<4%). Site comparison indicated limited ability to separate leaf transmittance but not reflectance by marsh type (e.g., low, medium, high) or biomass. Excluding one outlier, we found leaf transmittances could be adequately represented as 1% ?? 0.2% in the visible and 9% ?? 1% in the NIR and leaf reflectances represented from 14% to 16% in the visible and 71% to 75% in the NIR (the reflectance ranges represent 1999 and 2002 means). Reflectance and transmittance spectra associated with the dead J. roemerianus leaves displayed a spectrally flat increase from the visible to the NIR wavelengths. In total, we documented the atypical optical properties of the cylindrical J. roemerianus leaves and showed that to a first approximation, single means could represent leaf transmittance and visible leaf reflectance across all marsh zones and, after accounting for sample standardization, possibly the NIR reflectance as well.
Terminalia ferdinandiana Exell. Extracts inhibit the growth of body odour-forming bacteria.
McManus, K; Wood, A; Wright, M H; Matthews, B; Greene, A C; Cock, I E
2017-10-01
Terminalia ferdinandiana extracts are potent growth inhibitors of many bacterial pathogens. They may also inhibit the growth of malodour-producing bacteria and thus be useful deodorant components, although this is yet to be tested. Terminalia ferdinandiana fruit and leaf solvent extracts were investigated by disc diffusion and liquid dilution MIC assays against the most significant bacterial contributors to axillary and plantar malodour formation. Toxicity was determined using the Artemia franciscana nauplii bioassay. Non-targeted HPLC separation of the methanolic leaf extract coupled to high-resolution time-of-flight (TOF) mass spectroscopy was used for the identification and characterization of individual components in the extract. The T. ferdinandiana leaf extracts were the most potent bacterial growth inhibitors. The leaf methanolic extract was particularly potent, with low MIC values against C. jeikeium (233 μg mL -1 ), S. epidermidis (220 μg mL -1 ), P. acnes (625 μg mL -1 ) and B. linens (523 μg mL -1 ). The aqueous and ethyl acetate leaf extracts were also potent growth inhibitors of C. jeikeium and S. epidermidis (MICs < 1000 μg mL -1 ). In comparison, the fruit extracts were substantially less potent antibacterial agents, although still with MIC values indicative of moderate growth inhibitory activity. All T. ferdinandiana leaf extracts were non-toxic in the Artemia franciscana bioassay. Non-biased phytochemical analysis of the methanolic leaf extract revealed the presence of high levels of and high diversity of tannins and high levels of the flavone luteolin. The low toxicity of the T. ferdinandiana leaf extracts and their potent growth inhibition of axillary and plantar malodour-producing bacteria indicate their potential as deodorant components. © 2017 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Krauss, Ken W.; Twilley, Robert R.; Doyle, Thomas W.; Gardiner, Emile S.
2006-01-01
We determined how different hydroperiods affected leaf gas exchange characteristics of greenhouse-grown seedlings (2002) and saplings (2003) of the mangrove species Avicennia germinans (L.) Stearn., Laguncularia racemosa (L.) Gaertn. f., and Rhizophora mangle L. Hydroperiod treatments included no flooding (unflooded), intermittent flooding (intermittent), and permanent flooding (flooded). Plants in the intermittent treatment were measured under both flooded and drained states and compared separately. In the greenhouse study, plants of all species maintained different leaf areas in the contrasting hydroperiods during both years. Assimilation–light response curves indicated that the different hydroperiods had little effect on leaf gas exchange characteristics in either seedlings or saplings. However, short-term intermittent flooding for between 6 and 22 days caused a 20% reduction in maximum leaf-level carbon assimilation rate, a 51% lower light requirement to attain 50% of maximum assimilation, and a 38% higher demand from dark respiration. Although interspecific differences were evident for nearly all measured parameters in both years, there was little consistency in ranking of the interspecific responses. Species by hydroperiod interactions were significant only for sapling leaf area. In a field study, R. mangle saplings along the Shark River in the Everglades National Park either demonstrated no significant effect or slight enhancement of carbon assimilation and water-use efficiency while flooded. We obtained little evidence that contrasting hydroperiods affect leaf gas exchange characteristics of mangrove seedlings or saplings over long time intervals; however, intermittent flooding may cause short-term depressions in leaf gas exchange. The resilience of mangrove systems to flooding, as demonstrated in the permanently flooded treatments, will likely promote photosynthetic and morphological adjustment to slight hydroperiod shifts in many settings..
Tuggle, B.N.; Friend, M.
1999-01-01
Gizzard worms are comprised of several species of parasitic nematodes or roundworms of birds. Severe infections can result in birds becoming unthrifty and debilitated to the extent that they are more susceptible to predation and to infection by other disease agents. The two gizzard worms that are emphasized here are trichostrongylid nematodes that belong to the genera Amidostomum sp. and Epomidiostomum sp. These long (10–35 millimeter), sometimes coiled, threadlike roundworms are found just beneath the surface lining and the grinding pads of the gizzard, and they are most frequently found in waterfowl. Other species of gizzard worms are found in upland gamebirds such as grouse, in psitticine birds such as parakeets, and in passerine or perching birds such as robins in various parts of the world.
Sheng, Ming; Gorzsás, András; Tuck, Simon
2016-01-01
Changes in intermediary metabolism have profound effects on many aspects of C. elegans biology including growth, development and behavior. However, many traditional biochemical techniques for analyzing chemical composition require relatively large amounts of starting material precluding the analysis of mutants that cannot be grown in large amounts as homozygotes. Here we describe a technique for detecting changes in the chemical compositions of C. elegans worms by Fourier transform infrared microspectroscopy. We demonstrate that the technique can be used to detect changes in the relative levels of carbohydrates, proteins and lipids in one and the same worm. We suggest that Fourier transform infrared microspectroscopy represents a useful addition to the arsenal of techniques for metabolic studies of C. elegans worms.
Kim, Mi Jung; Jin, Jingjing; Zheng, Junshi
2015-01-01
Stevia (Stevia rebaudiana) produces not only a group of diterpenoid glycosides known as steviol glycosides (SGs), but also other labdane-type diterpenoids that may be spatially separated from SGs. However, their biosynthetic routes and spatial distribution in leaf tissues have not yet been elucidated. Here, we integrate metabolome and transcriptome analyses of Stevia to explore the biosynthetic capacity of leaf tissues for diterpenoid metabolism. Tissue-specific chemical analyses confirmed that SGs were accumulated in leaf cells but not in trichomes. On the other hand, Stevia leaf trichomes stored other labdane-type diterpenoids such as oxomanoyl oxide and agatholic acid. RNA sequencing analyses from two different tissues of Stevia provided a comprehensive overview of dynamic metabolic activities in trichomes and leaf without trichomes. These metabolite-guided transcriptomics and phylogenetic and gene expression analyses clearly identified specific gene members encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate pathway and the biosynthesis of steviol or other labdane-type diterpenoids. Additionally, our RNA sequencing analysis uncovered copalyl diphosphate synthase (SrCPS) and kaurene synthase1 (SrKS1) homologs, SrCPS2 and KS-like (SrKSL), which were specifically expressed in trichomes. In vitro and in planta assays showed that unlike SrCPS and SrKS1, SrCPS2 synthesized labda-13-en-8-ol diphosphate and successively catalyzed the formation of manoyl oxide and epi-manoyl oxide in combination with SrKSL. Our findings suggest that Stevia may have evolved to use distinct metabolic pathways to avoid metabolic interferences in leaf tissues for efficient production of diverse secondary metabolites. PMID:26438788
Complete mitochondrial genome sequence of Urechis caupo, a representative of the phylum Echiura
Boore, Jeffrey L
2004-01-01
Background Mitochondria contain small genomes that are physically separate from those of nuclei. Their comparison serves as a model system for understanding the processes of genome evolution. Although hundreds of these genome sequences have been reported, the taxonomic sampling is highly biased toward vertebrates and arthropods, with many whole phyla remaining unstudied. This is the first description of a complete mitochondrial genome sequence of a representative of the phylum Echiura, that of the fat innkeeper worm, Urechis caupo. Results This mtDNA is 15,113 nts in length and 62% A+T. It contains the 37 genes that are typical for animal mtDNAs in an arrangement somewhat similar to that of annelid worms. All genes are encoded by the same DNA strand which is rich in A and C relative to the opposite strand. Codons ending with the dinucleotide GG are more frequent than would be expected from apparent mutational biases. The largest non-coding region is only 282 nts long, is 71% A+T, and has potential for secondary structures. Conclusions Urechis caupo mtDNA shares many features with those of the few studied annelids, including the common usage of ATG start codons, unusual among animal mtDNAs, as well as gene arrangements, tRNA structures, and codon usage biases. PMID:15369601
On the Relationship Between Hyperspectral Data and Foliar Nitrogen Content in Closed Canopy Forests
NASA Astrophysics Data System (ADS)
Knyazikhin, Y.; Schull, M.; Lepine, L. C.; Stenberg, P.; Mõttus, M.; Rautiainen, M.; Latorre, P.; Myneni, R.; Kaufmann, R.
2011-12-01
The importance of nitrogen for terrestrial ecosystem carbon dynamics and its climate feedback has been well recognized by the ecological community. Interaction between carbon and nitrogen at leaf level is among the fundamental mechanisms that directly control the dynamics of terrestrial vegetation carbon. This process influences absorption and scattering of solar radiation by foliage, which in turn impacts radiation reflected by the vegetation and measured by satellite sensors. NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and ground based data on canopy structure and foliage nitrogen concentration acquired over six sites in Maine, New England, Florida, North Carolina and Washington were analyzed to assess the role of canopy structure, leaf optics and its biochemical constituents in the spectral variation of radiation reflected by the forest. The study sites represent closed canopy forests (LAI~5). Our results suggest: 1. Impact of canopy structure is so strong that it can significantly suppress the sensitivity of hyperspectral data to leaf optics. 2. Forest reflectance spectra in the interval [710, 790 nm] are required to obtain the fraction of the total leaf area that a "sensor sees" in a given direction. For closed canopy forests its retrieval does not require canopy reflectance models, suggesting that canopy reflectance spectra in this interval provide a direct estimate of the leaf area fraction. 3. The leaf area fraction fully explains variation in measured reflectance spectra due to variation in canopy structure. This variable is used to estimate the mean leaf scattering over foliage that the "sensor sees." For example the nadir-viewing AVIRIS sensor accumulates foliage optical properties over 25% of the total foliage area in needle leaf forest and about 50% in broadleaf forest. 4. Leaf surface properties have an impact on forest reflectivity, lowering its sensitivity to leaf absorbing pigments. 5. Variation in foliar nitrogen concentration can explain up to 55% of variation in AVIRIS spectra in the interval between 400 and 900 nm. The remaining factors could be due to (a) impact of leaf surface properties and/or (b) under-sampling of leaf optical properties due to the single view of the AVIRIS sensor. The theory of canopy spectral invariants underlies the separation of leaf scattering from the total canopy reflectance spectrum.
Ďurkovič, Jaroslav; Čaňová, Ingrid; Lagaňa, Rastislav; Kučerová, Veronika; Moravčík, Michal; Priwitzer, Tibor; Urban, Josef; Dvořák, Miloň; Krajňáková, Jana
2013-01-01
Background and Aims Previous studies have shown that Ophiostoma novo-ulmi, the causative agent of Dutch elm disease (DED), is able to colonize remote areas in infected plants of Ulmus such as the leaf midrib and secondary veins. The objective of this study was to compare the performances in leaf traits between two Dutch elm hybrids ‘Groeneveld’ and ‘Dodoens’ which possess a contrasting tolerance to DED. Trait linkages were also tested with leaf mass per area (LMA) and with the reduced Young's modulus of elasticity (MOE) as a result of structural, developmental or functional linkages. Methods Measurements and comparisons were made of leaf growth traits, primary xylem density components, gas exchange variables and chlorophyll a fluorescence yields between mature plants of ‘Groeneveld’ and ‘Dodoens’ grown under field conditions. A recently developed atomic force microscopy technique, PeakForce quantitative nanomechanical mapping, was used to reveal nanomechanical properties of the cell walls of tracheary elements such as MOE, adhesion and dissipation. Key Results ‘Dodoens’ had significantly higher values for LMA, leaf tissue thickness variables, tracheary element lumen area (A), relative hydraulic conductivity (RC), gas exchange variables and chlorophyll a fluorescence yields. ‘Groeneveld’ had stiffer cell walls of tracheary elements, and higher values for water-use efficiency and leaf water potential. Leaves with a large carbon and nutrient investment in LMA tended to have a greater leaf thickness and a higher net photosynthetic rate, but LMA was independent of RC. Significant linkages were also found between the MOE and some vascular traits such as RC, A and the number of tracheary elements per unit area. Conclusions Strong dissimilarities in leaf trait performances were observed between the examined Dutch elm hybrids. Both hybrids were clearly separated from each other in the multivariate leaf trait space. Leaf growth, vascular and gas exchange traits in the infected plants of ‘Dodoens’ were unaffected by the DED fungus. ‘Dodoens’ proved to be a valuable elm germplasm for further breeding strategies. PMID:23264236
Papanatsiou, Maria; Amtmann, Anna; Blatt, Michael R
2017-04-01
Stomata are microscopic pores formed by specialized cells in the leaf epidermis and permit gaseous exchange between the interior of the leaf and the atmosphere. Stomata in most plants are separated by at least one epidermal pavement cell and, individually, overlay a single substomatal cavity within the leaf. This spacing is thought to enhance stomatal function. Yet, there are several genera naturally exhibiting stomata in clusters and therefore deviating from the one-cell spacing rule with multiple stomata overlaying a single substomatal cavity. We made use of two Begonia species to investigate whether clustering of stomata alters guard cell dynamics and gas exchange under different light and dark treatments. Begonia plebeja, which forms stomatal clusters, exhibited enhanced kinetics of stomatal conductance and CO2 assimilation upon light stimuli that in turn were translated into greater water use efficiency. Our findings emphasize the importance of spacing in stomatal clusters for gaseous exchange and plant performance under environmentally limited conditions. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Denyes, Mackenzie J; Rutter, Allison; Zeeb, Barbara A
2013-11-01
The in situ use of carbon amendments such as activated carbon (AC) and biochar to minimize the bioavailability of organic contaminants is gaining in popularity. In the first in situ experiment conducted at a Canadian PCB-contaminated Brownfield site, GAC and two types of biochar were statistically equal at reducing PCB uptake into plants. PCB concentrations in Cucurbita pepo root tissue were reduced by 74%, 72% and 64%, with the addition of 2.8% GAC, Burt's biochar and BlueLeaf biochar, respectively. A complementary greenhouse study which included a bioaccumulation study of Eisenia fetida (earthworm), found mechanically mixing carbon amendments with PCB-contaminated soil (i.e. 24 h at 30 rpm) resulted in shoot, root and worm PCB concentrations 66%, 59% and 39% lower than in the manually mixed treatments (i.e. with a spade and bucket). Therefore, studies which mechanically mix carbon amendments with contaminated soil may over-estimate the short-term potential to reduce PCB bioavailability. Copyright © 2013 Elsevier Ltd. All rights reserved.
Determination of saponins and flavonoids in ivy leaf extracts using HPLC-DAD.
Yu, Miao; Shin, Young June; Kim, Nanyoung; Yoo, Guijae; Park, SeonJu; Kim, Seung Hyun
2015-04-01
A new method for the determination of six compounds, chlorogenic acid, rutin, nicotiflorin, hederacoside C, hederasaponin B and α-hederin, in ivy leaf extracts using high-performance liquid chromatography with diode array detector was developed. The chromatographic separation was performed on a YMC Hydrosphere C18 analytical column using a gradient elution of 0.1% phosphoric acid and acetonitrile. The method was validated in terms of specificity, linearity (r(2) > 0.9999), precision [relative standard deviation (RSD) < 0.36%] and accuracy (97.4-103.8%). The limit of detection and limit of quantification were <20.32 and 61.56 ng for all analytes, respectively. The tested compounds were found to be stable in the ivy leaf extract from 0 to 48 h, and the RSD value for each compound was <0.90%. The validated method was successfully applied to quantify all six compounds in a 30% ethanol ivy leaf extract and 13 ivy leaf extract products. The results showed that all the tested products satisfied the minimum requirement for the content of hederacoside C. However, there were some differences between the contents of other constituents. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Teakle, Natasha Lea; Colmer, Timothy David; Pedersen, Ole
2014-10-01
A combination of flooding and salinity is detrimental to most plants. We studied tolerance of complete submergence in saline water for Melilotus siculus, an annual legume with superhydrophobic leaf surfaces that retain gas films when under water. M. siculus survived complete submergence of 1 week at low salinity (up to 50 mol m(-3) NaCl), but did not recover following de-submergence from 100 mol m(-3) NaCl. The leaf gas films protected against direct salt ingress into the leaves when submerged in saline water, enabling underwater photosynthesis even after 3 d of complete submergence. By contrast, leaves with the gas films experimentally removed suffered from substantial Na(+) and Cl(-) intrusion and lost the capacity for underwater photosynthesis. Similarly, plants in saline water and without gas films lost more K(+) than those with intact gas films. This study has demonstrated that leaf gas films reduce Na(+) and Cl(-) ingress into leaves when submerged by saline water - the thin gas layer physically separates the floodwater from the leaf surface. This feature aids survival of plants exposed to short-term saline submergence, as well as the previously recognized beneficial effects of gas exchange under water. © 2014 John Wiley & Sons Ltd.
Wolken, Sonja; Böhm, Claudia; Schaper, Roland; Schnieder, Thomas
2012-11-01
Toxocara cati is the most prevalent gastrointestinal helminth in cats worldwide, with cats of all ages at risk of infection. An anthelminthic treatment that not only affects the gut-dwelling stages of this parasite but is also effective against developmental stages in the tissue has the advantage that the pathology caused by migrating larvae is minimized and the need for repeated treatments is reduced. This study was conducted to evaluate the efficacy of milbemycin oxime/praziquantel tablets (Milbemax®, Novartis) against third-stage larvae of T. cati in comparison to a spot-on formulation of emodepside and praziquantel (Profender®, Bayer). Twenty-four kittens were experimentally infected with T. cati and randomly allocated to three study groups. Treatments were performed at the minimum therapeutic dosage 5 days after the experimental infection. The development of patent infections was monitored and all cats were dewormed 50 days post-infection. Efficacies were calculated based on counts of excreted worms in the treated groups compared to a negative control group. Seven of the eight cats in the negative control group developed a patent T. cati infection and all cats were excreting worms at the end of the study (geometric mean worm count 18.1). No efficacy could be observed for the milbemycin oxime-treated animals. All cats developed a patent infection and excreted worms (geometric mean worm count 27.7). The treatment with Profender® was 98.5 % effective against L3 of T. cati. One cat developed a patent infection and was excreting worms at the end of the study (geometric mean worm count 0.3). No adverse reactions were noted in either treatment group.
Preparation of Pickering Double Emulsions Using Block Copolymer Worms
2015-01-01
The rational formulation of Pickering double emulsions is described using a judicious combination of hydrophilic and hydrophobic block copolymer worms as highly anisotropic emulsifiers. More specifically, RAFT dispersion polymerization was utilized to prepare poly(lauryl methacrylate)–poly(benzyl methacrylate) worms at 20% w/w solids in n-dodecane and poly(glycerol monomethacrylate)–poly(2-hydroxypropyl methacrylate)–poly(benzyl methacrylate) worms at 13% w/w solids in water by polymerization-induced self-assembly (PISA). Water-in-oil-in-water (w/o/w) double emulsions can be readily prepared with mean droplet diameters ranging from 30 to 80 μm using a two-stage approach. First, a w/o precursor emulsion comprising 25 μm aqueous droplets is prepared using the hydrophobic worms, followed by encapsulation within oil droplets stabilized by the hydrophilic worms. The double emulsion droplet diameter and number of encapsulated water droplets can be readily varied by adjusting the stirring rate employed during the second stage. For each stage, the droplet volume fraction is relatively high at 0.50. The double emulsion nature of the final formulation was confirmed by optical and fluorescence microscopy studies. Such double emulsions are highly stable to coalescence, with little or no change in droplet diameter being detected over storage at 20 °C for 10 weeks as judged by laser diffraction. Preliminary experiments indicate that the complementary o/w/o emulsions can also be prepared using the same pair of worms by changing the order of homogenization, although somewhat lower droplet volume fractions were required in this case. Finally, we demonstrate that triple and even quadruple emulsions can be formulated using these new highly anisotropic Pickering emulsifiers. PMID:25834923
Mortality of Rocky Mountain elk in Michigan due to meningeal worm.
Bender, Louis C; Schmitt, Stephen M; Carlson, Elaine; Haufler, Jonathan B; Beyer, Dean E
2005-01-01
Mortality from cerebrospinal parelaphostrongylosis caused by the meningeal worm (Parelaphostrongylus tenuis) has been hypothesized to limit elk (Cervus elaphus nelsoni) populations in areas where elk are conspecific with white-tailed deer (Odocoileus virginianus). Elk were reintroduced into Michigan (USA) in the early 1900s and subsequently greatly increased population size and distribution despite sympatric high-density (>or=12/km2) white-tailed deer populations. We monitored 100 radio-collared elk of all age and sex classes from 1981-94, during which time we documented 76 mortalities. Meningeal worm was a minor mortality factor for elk in Michigan and accounted for only 3% of mortalities, fewer than legal harvest (58%), illegal kills (22%), other diseases (7%), and malnutrition (4%). Across years, annual cause-specific mortality rates due to cerebrospinal parelaphostrongylosis were 0.033 (SE=0.006), 0.029 (SE=0.005), 0.000 (SE=0.000), and 0.000 (SE=0.000) for calves, 1-yr-old, 2-yr-old, and >or=3-yr-old, respectively. The overall population-level mortality rate due to cerebrospinal parelaphostrongylosis was 0.009 (SE=0.001). Thus, meningeal worm had little impact on elk in Michigan during our study despite greater than normal precipitation (favoring gastropods) and record (>or=14 km2) deer densities. Further, elk in Michigan have shown sustained population rates-of-increase of >or=18%/yr and among the highest levels of juvenile production and survival recorded for elk in North America, indicating that elk can persist in areas with meningeal worm at high levels of population productivity. It is likely that local ecologic characteristics among elk, white-tailed deer, and gastropods, and degree of exposure, age of elk, individual and population experience with meningeal worm, overall population vigor, and moisture determine the effects of meningeal worm on elk populations.
Mortality of rocky mountain elk in Michigan due to meningeal worm
Bender, L.C.; Schmitt, S.M.; Carlson, E.; Haufler, J.B.; Beyer, D.E.
2005-01-01
Mortality from cerebrospinal parelaphostrongylosis caused by the meningeal worm (Parelaphostrongylus tenuis) has been hypothesized to limit elk (Cervus elaphus nelsoni) populations in areas where elk are conspecific with white-tailed deer (Odocoileus virginianus). Elk were reintroduced into Michigan (USA) in the early 1900s and subsequently greatly increased population size and distribution despite sympatric high-density (???12/km2) white-tailed deer populations. We monitored 100 radio-collared elk of all age and sex classes from 1981-94, during which time we documented 76 mortalities. Meningeal worm was a minor mortality factor for elk in Michigan and accounted for only 3% of mortalities, fewer than legal harvest (58%), illegal kills (22%), other diseases (7%), and malnutrition (4%). Across years, annual cause-specific mortality rates due to cerebrospinal parelaphostrongylosis were 0.033 (SE=0.006), 0.029 (SE=0.005), 0.000 (SE=0.001), and 0.000 (SE=0.000) for calves, 1-yr-old, 2-yr-old, and ???3-yr-old, respectively. The overall population-level mortality rate due to cerebrospinal parelaphostrongylosis was 0.009 (SE=0.001). Thus, meningeal worm had little impact on elk in Michigan during our study despite greater than normal precipitation (favoring gastropods) and record (???14 km2) deer densities. Further, elk in Michigan have shown sustained population rates-of-increase of ???18%/yr and among the highest levels of juvenile production and survival recorded for elk in North America, indicating that elk can persist in areas with meningeal worm at high levels of population productivity. it is likely that local ecologic characteristics among elk, white-tailed deer, and gastropods, and degree of exposure, age of elk, individual and population experience with meningeal worm, overall population vigor, and moisture determine the effects of meningeal worm on elk populations. ?? Wildlife Disease Association 2005.
Eradicating guinea worm without wells: unrealized hopes of the Water Decade.
Brieger, W R; Otusanya, S; Adeniyi, J D; Tijani, J; Banjoko, M
1997-12-01
At the start of the United Nations International Drinking Water Supply and Sanitation Decade in the 1980s, guinea worm disease was targeted as the major indicator of the success of the Decade's efforts to promote safe water. By the late 1980s, most of the guinea worm endemic countries in Africa and South Asia had established guinea worm eradication programmes that included water supply as one of their main technical strategies. By surveying the water supply situation in Ifeloju Local Government Area (LGA) in Oyo State, Nigeria, in June 1996, as a case study, it was possible to determine the role that water supply has played in the eradication effort. Although two major agencies, the former Directorate for Food, Roads and Rural Infrastructure and UNICEF, provided hand dug and bore-hole wells respectively in many parts of the LGA, coverage of the smaller farm hamlets has been minor compared to efforts in the larger towns. This is ironic because the farm hamlets served as a reservoir for the disease in the 1980s, such that when the piped water system in the towns broke down, guinea worm was easily reintroduced into the towns. The survey of 188 ever-endemic hamlets with an estimated population of 23,556 found that 74.3% of the people still drink only pond water. Another 11.3% have wells that have become dysfunctional. Only 14.4% of this rural population has access' to functioning wells. Guinea worm was eliminated from 107 of the hamlets mainly by the use of cloth filters and chemical treatment of ponds. While this proves that it is possible to eradicate guinea worm, it fails to leave behind the legacy of reliable, safe water supplies that was the hope of the Water Decade.
Nakagawa, Haruka; Ishizu, Hirotsugu; Hasegawa, Reiko; Kobayashi, Kazuya; Matsumoto, Midori
2012-01-01
A piwi homolog is required for the regulation of stem cells, formation and maintenance of germline stem cells, and gametogenesis in many metazoans. Planarians can change their reproductive mode seasonally, both asexually and sexually, and develop and maintain germ cells and sexual organs. They have many pluripotent stem cells (neoblasts) that can differentiate into both somatic and germline stem cells. Thus, we searched for a piwi subfamily in the planarian Dugesia ryukyuensis. Four piwi homologs, identified as Drpiwi-1, -2, -3, and -4, were expressed in sexually reproductive worms. We then selectively destroyed the neoblasts by irradiating the worms with X-rays. In such worms, Drpiwi-1, -2, and -3 were not expressed at all, whereas Drpiwi-4 was expressed to the same degree as that in non-irradiated controls, indicating that Drpiwi-1, -2, and -3, but not Drpiwi-4, are expressed in neoblasts. During the regeneration process, Drpiwi-2(RNAi) and -3(RNAi) worms failed to regenerate after ablation, but Drpiwi-1 and -4(RNAi) worms regenerated. During the sexualizing process, Drpiwi-1(RNAi) worms failed to develop ovaries and testes, but somatic sexual organs were unaffected. Germ cell development was normal in Drpiwi-4(RNAi) worms. Therefore, Drpiwi-2 and -3 may be related to the regulation of neoblasts important for maintaining homeostasis, and Drpiwi-1 is essential for the development of germ cells but not somatic sexual organs. DrPiwi-1 is localized in the cytoplasm of stem cells and germline cells and may be involved in regulating some gene expression. We suggest that planarian Piwi controls germline formation via RNA silencing mechanisms. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.
Predicting path from undulations for C. elegans using linear and nonlinear resistive force theory.
Keaveny, Eric E; Brown, André E X
2017-03-22
A basic issue in the physics of behaviour is the mechanical relationship between an animal and its surroundings. The model nematode C. elegans provides an excellent platform to explore this relationship due to its anatomical simplicity. Nonetheless, the physics of nematode crawling, in which the worm undulates its body to move on a wet surface, is not completely understood and the mathematical models often used to describe this phenomenon are empirical. We confirm that linear resistive force theory, one such empirical model, is effective at predicting a worm's path from its sequence of body postures for forward crawling, reversing, and turning and for a broad range of different behavioural phenotypes observed in mutant worms. Worms recently isolated from the wild have a higher effective drag anisotropy than the laboratory-adapted strain N2 and most mutant strains. This means the wild isolates crawl with less surface slip, perhaps reflecting more efficient gaits. The drag anisotropies required to fit the observed locomotion data (70 ± 28 for the wild isolates) are significantly larger than the values measured by directly dragging worms along agar surfaces (3-10 in Rabets et al (2014 Biophys. J. 107 1980-7)). A proposed nonlinear extension of the resistive force theory model also provides accurate predictions, but does not resolve the discrepancy between the parameters required to achieve good path prediction and the experimentally measured parameters. We confirm that linear resistive force theory provides a good effective model of worm crawling that can be used in applications such as whole-animal simulations and advanced tracking algorithms, but that the nature of the physical interaction between worms and their most commonly studied laboratory substrate remains unresolved.
1978-11-30
migration(diurnal) of Mycophidae and siphonophores of the suborder Physonectae. —2— _______ - ~~~~~~~~~~ _____________________________ I-~ The former...ORGANISMS PLANKTON COPEPODS TRANSLUCENT ! ARROW WORMS TRANSPARENT SIPHONOPHORES MEDUSAE AGLISCRA IGNEA FLAMING RED NEMERTEAN WORMS REDDISH ARROW WORMS...383-385 ( 1969) 9. BARHAN, Eric G., Siphonophores and the Deep Scattering Layer, Science, 140, 826—828 (1963) 10. BARHA~M , Eric C., Deep Scattering
Worm Grunting, Fiddling, and Charming—Humans Unknowingly Mimic a Predator to Harvest Bait
Catania, Kenneth C.
2008-01-01
Background For generations many families in and around Florida's Apalachicola National Forest have supported themselves by collecting the large endemic earthworms (Diplocardia mississippiensis). This is accomplished by vibrating a wooden stake driven into the soil, a practice called “worm grunting”. In response to the vibrations, worms emerge to the surface where thousands can be gathered in a few hours. Why do these earthworms suddenly exit their burrows in response to vibrations, exposing themselves to predation? Principal Findings Here it is shown that a population of eastern American moles (Scalopus aquaticus) inhabits the area where worms are collected and that earthworms have a pronounced escape response from moles consisting of rapidly exiting their burrows to flee across the soil surface. Recordings of vibrations generated by bait collectors and moles suggest that “worm grunters” unknowingly mimic digging moles. An alternative possibility, that worms interpret vibrations as rain and surface to avoid drowning is not supported. Conclusions Previous investigations have revealed that both wood turtles and herring gulls vibrate the ground to elicit earthworm escapes, indicating that a range of predators may exploit the predator-prey relationship between earthworms and moles. In addition to revealing a novel escape response that may be widespread among soil fauna, the results show that humans have played the role of “rare predators” in exploiting the consequences of a sensory arms race. PMID:18852902
Distribution and movement of Caenorhabditis elegans on a thermal gradient.
Yamada, Yohko; Ohshima, Yasumi
2003-08-01
To analyze thermal responses of Caenorhabditis elegans in detail, distribution of a worm population and movement of individual worms were examined on a linear, reproducible and broad temperature gradient. Assay methods were improved compared with those reported previously to ensure good motility and dispersion of worms. Well-fed, wild-type worms distributed over a wide temperature range of up to 10 degrees C, and, within this range, worms migrated in both directions of the gradient at similar frequencies without any specific response to the growth temperature in most cases. By contrast, worms migrated down the gradient if put in a region warmer than the warm boundary of distribution. The distribution range changed depending on the growth temperature and starvation, but active avoidance of a starvation temperature was not detected. These findings contradict previous hypotheses of taxis or migration to the growth temperature in association with food and instead indicate avoidance of a warm temperature. Our results favor a model for thermal response of C. elegans that postulates a single drive based on warm sensation rather than downward and upward drives in the physiological temperature range. Mutants in ttx-3, tax-2, tax-4 or egl-4 genes showed abnormal thermal responses, suggesting that these genes are involved in warm avoidance. Laser ablation and gene expression studies suggest that AFD neurons are not important, and tax-4 expression in neurons other than AFD is required, for warm avoidance.
Wannasan, Anchalee; Khositharattanakool, Pathamet; Chaiwong, Prasong; Piangjai, Somsak; Uparanukraw, Pichart; Morakote, Nimit
2014-11-01
Molecular techniques were used to identify Fasciola species collected from Chiang Mai Thailand. Morphometrically, 65 stained and 45 fresh worms collected from cattle suggested the possible occurrence of both F. gigantica and F. hepatica. Twenty-two worms comprising 15 from cattle and 7 from human patients, were identified subsequently based on three genetic markers: mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit 1 (nad1), mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear ribosomal internal transcribed spacer 2 (ITS2). All of them presented the F. gigantica type in maternally inherited mitochondrial sequences (nad1 and cox1), with six types in each sequence (FgNDI-CM1 to FgNDI-CM6 and FgCOI-CM1 to FgCOI-CM6, respectively). Remarkably, the predominant nad1 type, FgNDI-CM6, was identical to that of aspermic Fasciola sp. formerly reported from Thailand, Japan, Korea, China, Vietnam, and Myanmar. ITS2 sequences were analyzed successfully in 20 worms. Fifteen worms showed the F. gigantica type and five (including one worm from a patient) had mixed ITS2 sequences of both F. gigantica and F. hepatica in the same worms, with additional heterogeneity within both ITS2 types. This study revealed the intermediate form of Fasciola coexisting with F. gigantica for the first time in Thailand.
Lee, Gisuk; Joo, Youngsung; Kim, Sang-Gyu; Baldwin, Ian T
2017-11-01
Herbivore attack is known to elicit systemic defense responses that spread throughout the host plant and influence the performance of other herbivores. While these plant-mediated indirect competitive interactions are well described, and the co-existence of herbivores from different feeding guilds is common, the mechanisms of co-existence are poorly understood. In both field and glasshouse experiments with a native tobacco, Nicotiana attenuata, we found no evidence of negative interactions when plants were simultaneously attacked by two spatially separated herbivores: a leaf chewer Manduca sexta and a stem borer Trichobaris mucorea. T. mucorea attack elicited jasmonic acid (JA) and jasmonoyl-l-isoleucine bursts in the pith of attacked stems similar to those that occur in leaves when M. sexta attacks N. attenuata leaves. Pith chlorogenic acid (CGA) levels increased 1000-fold to levels 6-fold higher than leaf levels after T. mucorea attack; these increases in pith CGA levels, which did not occur in M. sexta-attacked leaves, required JA signaling. With plants silenced in CGA biosynthesis (irHQT plants), CGA, as well as other caffeic acid conjugates, was demonstrated in both glasshouse and field experiments to function as a direct defense protecting piths against T. mucorea attack, but not against leaf chewers or sucking insects. T. mucorea attack does not systemically activate JA signaling in leaves, while M. sexta leaf-attack transiently induces detectable but minor pith JA levels that are dwarfed by local responses. We conclude that tissue-localized defense responses allow tissue-specialized herbivores to share the same host and occupy different chemical defense niches in the same hostplant. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.
Gutterman, Yitzchak; Chauser-Volfson, Elena
2008-10-01
Aloe arborescens plants, originating from the deserts of South Africa, are grown in the Introduction Garden at Sede Boker in the Negev Desert of Israel. In previous studies, we developed agro-technical methods to raise the content of secondary phenol metabolites (SPhMs) in the Aloe leaves. Plants that are subjected to repeated leaf pruning respond by increasing the content of their SPhMs. The SPhMs found in Aloe arborescens include barbaloin, aloenin and derivatives of aloeresin. Such compounds are used for many purposes, including human skin protection from sun and fire burns and high radiation, as products of the pharmaceutics and cosmetics industries, and as food supplements for treating stomach ulcers and diabetes. In the current study, the SPhMs were separated from pruned leaves of the same A. arborescens plants at the same time by two methods: (1) exudation by squeezing the tissues of the leaves, (2) immersion of the leaves' pruned cut bottom in water and collection of the extract. The exudates and extract were frozen, freeze-dried to a powder and the SPhMs were then separated by chromatography. The yield of powder from water extraction from pruned leaves was much lower than the yield from the exudates. However, higher percentages of the powder from the water extraction contained SPhMs (between 80 and 92.7%). The content of powder in leaf exudates from pruned leaves was much higher because the SPhMs were squeezed out from the cells and tissues. However, the percentages of SPhMs in this powder were much lower (between 39 and 62%).
Poster — Thur Eve — 19: Performance assessment of a 160-leaf beam collimation system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, E. S. M.; La Russa, D. J.; Vandervoort, E.
2014-08-15
In this study, the performance of the new beam collimation system with 160 leaves, each with a 5 mm leaf width projected at isocenter, is evaluated in terms of positional accuracy and plan/delivery quality. Positional accuracy was evaluated using a set of static and dynamic MLC/jaw delivery patterns at different gantry angles, dose rates, and MLC/jaw speeds. The impact on IMRT plan quality was assessed by comparing against a previous generation collimation system using the same optimization parameters, while delivery quality was quantified using a combination of patient-specific QA measurements with ion chambers, film, and a bi-planar diode array. Positionalmore » accuracy for four separate units was comparable. The field size accuracy, junction width, and total displacement over 16 cm leaf travel are 0.3 ± 0.2 mm, 0.4 ± 0.3 mm, and 0.5 ± 0.2 mm, respectively. The typical leaf minor offset is 0.05 ± 0.04 mm, and MLC hysteresis effects are 0.2 ± 0.1 mm over 16 cm travel. The dynamic output is linear with MU and MLC/jaw speed, and is within 0.7 ± 0.3 % of the planning system value. Plan quality is significantly improved both in terms of target coverage and OAR sparing due, in part, to the larger allowable MLC and jaw speeds. γ-index pass rates for the patient-specific QA measurements exceeded 97% using criteria of 2%/2 mm. In conclusion, the performance of the Agility system is consistent among four separate installations, and is superior to its previous generations of collimation systems.« less
... used to treat certain other worm infestations, including tapeworm (a type of worm that may attach to ... have ocular cysticercosis (infestation with a type of tapeworm that forms cysts in the eyes). Your doctor ...
Beauchamp, Katherine A; El-Matbouli, Mansour; Gay, Melanie; Georgiadis, Marios P; Nehring, R Barry; Hedrick, Ronald P
2006-01-01
The competitive interactions between susceptible and resistant Tubifex tubifex (Oligochaeta: Tubificidae) exposed to Myxobolus cerebralis (Myxozoa: Myxobolidae) infections were investigated in two laboratory trials. Competition was assessed by the total parasite production over the course of the trials in mixed and pure cultures of M. cerebralis exposed worms, and by the genetic analyses of worms from the control and experimental groups at the beginning and end of the experiments. Mixed cultures of resistant and susceptible worms showed a 70% reduction in production of parasites released when compared with pure cultures of susceptible worms. In studies with laboratory and field-collected oligochaetes the mixed cultures at the end of the cohabitation experiments were dominated by resistant Tubifex from lineage V (HB strain) this strain of Tubifex has a competitive advantage over worms from other lineages. The results of this study suggest that certain species of Tubifex may be dead-end hosts to M. cerebralis by absorbing or inactivating the parasite and may also show greater survival compared to susceptible oligochaetes in certain whirling disease enzootic habitats.
Chiu, Ming-Chung; Huang, Chin-Gi; Wu, Wen-Jer; Shiao, Shiuh-Feng
2016-06-01
The life cycle of the freshwater horsehair worm typically includes a free-living phase (adult, egg, larva) and a multiple-host parasitic phase (aquatic paratenic host, terrestrial definitive host). Such a life cycle involving water and land can improve energy flow in riparian ecosystems; however, its temporal dynamics in nature have rarely been investigated. This study examined seasonal infection with cysts in larval Chironominae (Diptera: Chironomidae) in northern Taiwan. In the larval chironomids, cysts of 3 horsehair worm species were identified. The cysts of the dominant species were morphologically similar to those of Chordodes formosanus. Infection with these cysts increased suddenly and peaked 2 mo after the reproductive season of the adult horsehair worms. Although adult C. formosanus emerged several times in a year, only 1 distinct infection peak was detected in September in the chironomid larvae. Compared with the subfamily Chironominae, samples from the subfamilies Tanypodinae and Orthocladiinae were less parasitized. This indicates that the feeding behavior of the chironomid host likely affects horsehair worm cyst infections; however, bioconcentration in predatory chironomids was not detected.
Waldrop, Thomas; Blazer, Vicki; Smith, David; Schill, Bane; Densmore, Christine; Schill, B.; Waldrop, T.; Blazer, V.
1999-01-01
Salmonid whirling disease is caused by Myxobolus cerebralis, a metazoan parasite with a two host life cycle involving salmonid fish a an aquatic oligochaete, Tubifex tubifex (Wolf, Markiw and Hiltunen, 1986). Whirling disease has been reported in 22 U.S. states with the greatest losses occurring in the salmonid fisheries of western and Midwestern states. Although whirling disease is endemic in the eastern United States, serious documented losses to wild populations have not been reported. Two high priority research needs identified in 1996 were a better understanding of how worm and parasite populations might differ from different geographic areas and how environmental factors affect the various stages of whirling disease. To begin to address these research needs we established "eastern" populations of worms, parasite and fish hosts. This abstract will present data on the effects of temperature and substrate upon eastern T. tubifex worms infected with an eastern isolate of M. cerebralis. The influences of these abiotic factors upon the ability to infect the worms and subsequently their ability to produce waterborne triactinomyxons.
WormBase 2014: new views of curated biology
Harris, Todd W.; Baran, Joachim; Bieri, Tamberlyn; Cabunoc, Abigail; Chan, Juancarlos; Chen, Wen J.; Davis, Paul; Done, James; Grove, Christian; Howe, Kevin; Kishore, Ranjana; Lee, Raymond; Li, Yuling; Muller, Hans-Michael; Nakamura, Cecilia; Ozersky, Philip; Paulini, Michael; Raciti, Daniela; Schindelman, Gary; Tuli, Mary Ann; Auken, Kimberly Van; Wang, Daniel; Wang, Xiaodong; Williams, Gary; Wong, J. D.; Yook, Karen; Schedl, Tim; Hodgkin, Jonathan; Berriman, Matthew; Kersey, Paul; Spieth, John; Stein, Lincoln; Sternberg, Paul W.
2014-01-01
WormBase (http://www.wormbase.org/) is a highly curated resource dedicated to supporting research using the model organism Caenorhabditis elegans. With an electronic history predating the World Wide Web, WormBase contains information ranging from the sequence and phenotype of individual alleles to genome-wide studies generated using next-generation sequencing technologies. In recent years, we have expanded the contents to include data on additional nematodes of agricultural and medical significance, bringing the knowledge of C. elegans to bear on these systems and providing support for underserved research communities. Manual curation of the primary literature remains a central focus of the WormBase project, providing users with reliable, up-to-date and highly cross-linked information. In this update, we describe efforts to organize the original atomized and highly contextualized curated data into integrated syntheses of discrete biological topics. Next, we discuss our experiences coping with the vast increase in available genome sequences made possible through next-generation sequencing platforms. Finally, we describe some of the features and tools of the new WormBase Web site that help users better find and explore data of interest. PMID:24194605
The opportunistic transmission of wireless worms between mobile devices
NASA Astrophysics Data System (ADS)
Rhodes, C. J.; Nekovee, M.
2008-12-01
The ubiquity of portable wireless-enabled computing and communications devices has stimulated the emergence of malicious codes (wireless worms) that are capable of spreading between spatially proximal devices. The potential exists for worms to be opportunistically transmitted between devices as they move around, so human mobility patterns will have an impact on epidemic spread. The scenario we address in this paper is proximity attacks from fleetingly in-contact wireless devices with short-range communication range, such as Bluetooth-enabled smart phones. An individual-based model of mobile devices is introduced and the effect of population characteristics and device behaviour on the outbreak dynamics is investigated. The model uses straight-line motion to achieve population, though it is recognised that this is a highly simplified representation of human mobility patterns. We show that the contact rate can be derived from the underlying mobility model and, through extensive simulation, that mass-action epidemic models remain applicable to worm spreading in the low density regime studied here. The model gives useful analytical expressions against which more refined simulations of worm spread can be developed and tested.
Determining density of maize canopy. 3: Temporal considerations
NASA Technical Reports Server (NTRS)
Stoner, E. R.; Baumgardner, M. F.; Anuta, P. E.; Cipra, J. E.
1972-01-01
Multispectral scanner data were collected in two flights over ground cover plots at an altitude of 305 m. Eight ground reflectance panels in close proximity to the ground cover plots were used to normalize the scanner data obtained on different dates. Separate prediction equations were obtained for both flight dates for all eleven reflective wavelength bands of the multispectral scanner. Ratios of normalized scanner data were related to leaf area index over time. Normalized scanner data were used to plot relative reflectance versus wavelength for the ground cover plots. Spectral response curves were similar to those for bare soil and green vegetation as determined by laboratory measurements. The spectral response curves from the normalized scanner data indicated that reflectance in the 0.72 to 1.3 micron wavelength range increased as leaf area index increased. A decrease in reflectance was observed in the 0.65 micron chlorophyll absorption band as leaf area index increased.
NASA Technical Reports Server (NTRS)
Hatfield, J. L.; Asrar, G.; Kanemasu, E. T.
1982-01-01
The interception of photosynthetically active radiation (PAR) was evaluated relative to greenness and normalized difference (MSS 7-5/7+5) for five planting dates of wheat for 1978-79 and 1979-80 in Phoenix. Intercepted PAR was calculated from a model driven by leaf area index and stage of growth. Linear relationships were found between greenness and normalized difference with a separate model representing growth and senescence of the crop. Normalized difference was a significantly better model and would be easier to apply than the empirically derived greenness parameter. For the leaf area growth portion of the season the model between PAR interception and normalized difference was the same over years, however, for the leaf senescence the models showed more variability due to the lack of data on measured interception in sparse canopies. Normalized difference could be used to estimate PAR interception directly for crop growth models.
Lectins with anti-HIV activity: a review.
Akkouh, Ouafae; Ng, Tzi Bun; Singh, Senjam Sunil; Yin, Cuiming; Dan, Xiuli; Chan, Yau Sang; Pan, Wenliang; Cheung, Randy Chi Fai
2015-01-06
Lectins including flowering plant lectins, algal lectins, cyanobacterial lectins, actinomycete lectin, worm lectins, and the nonpeptidic lectin mimics pradimicins and benanomicins, exhibit anti-HIV activity. The anti-HIV plant lectins include Artocarpus heterophyllus (jacalin) lectin, concanavalin A, Galanthus nivalis (snowdrop) agglutinin-related lectins, Musa acuminata (banana) lectin, Myrianthus holstii lectin, Narcissus pseudonarcissus lectin, and Urtica diocia agglutinin. The anti-HIV algal lectins comprise Boodlea coacta lectin, Griffithsin, Oscillatoria agardhii agglutinin. The anti-HIV cyanobacterial lectins are cyanovirin-N, scytovirin, Microcystis viridis lectin, and microvirin. Actinohivin is an anti-HIV actinomycete lectin. The anti-HIV worm lectins include Chaetopterus variopedatus polychaete marine worm lectin, Serpula vermicularis sea worm lectin, and C-type lectin Mermaid from nematode (Laxus oneistus). The anti-HIV nonpeptidic lectin mimics comprise pradimicins and benanomicins. Their anti-HIV mechanisms are discussed.
OpenWorm: an open-science approach to modeling Caenorhabditis elegans.
Szigeti, Balázs; Gleeson, Padraig; Vella, Michael; Khayrulin, Sergey; Palyanov, Andrey; Hokanson, Jim; Currie, Michael; Cantarelli, Matteo; Idili, Giovanni; Larson, Stephen
2014-01-01
OpenWorm is an international collaboration with the aim of understanding how the behavior of Caenorhabditis elegans (C. elegans) emerges from its underlying physiological processes. The project has developed a modular simulation engine to create computational models of the worm. The modularity of the engine makes it possible to easily modify the model, incorporate new experimental data and test hypotheses. The modeling framework incorporates both biophysical neuronal simulations and a novel fluid-dynamics-based soft-tissue simulation for physical environment-body interactions. The project's open-science approach is aimed at overcoming the difficulties of integrative modeling within a traditional academic environment. In this article the rationale is presented for creating the OpenWorm collaboration, the tools and resources developed thus far are outlined and the unique challenges associated with the project are discussed.
Li, Xiaoqiong; Guo, Wenfeng; Siemann, Evan; Wen, Yuanguang; Huang, Wei; Ding, Jianqing
2016-12-01
Spatially separated aboveground (AG) and belowground (BG) herbivores are closely linked through shared host plants, and both patterns of AG-BG interactions and plant responses may vary among plant genotypes. We subjected invasive (USA) and native (China) genotypes of tallow tree (Triadica sebifera) to herbivory by the AG specialist leaf-rolling weevil Heterapoderopsis bicallosicollis and/or the root-feeding larvae of flea beetle Bikasha collaris. We measured leaf damage and leaves rolled by weevils, quantified beetle survival, and analyzed flavonoid and tannin concentrations in leaves and roots. AG and BG herbivores formed negative feedbacks on both native and invasive genotypes. Leaf damage by weevils and the number of beetle larvae emerging as adults were higher on invasive genotypes. Beetles reduced weevil damage and weevils reduced beetle larval emergence more strongly for invasive genotypes. Invasive genotypes had lower leaf and root tannins than native genotypes. BG beetles decreased leaf tannins of native genotypes but increased root tannins of invasive genotypes. AG herbivory increased root flavonoids of invasive genotypes while BG herbivory decreased leaf flavonoids. Invasive genotypes had lower AG and BG herbivore resistance, and negative AG-BG herbivore feedbacks were much stronger for invasive genotypes. Lower tannin concentrations explained overall better AG and BG herbivore performances on invasive genotypes. However, changes in tannins and flavonoids affected AG and BG herbivores differently. These results suggest that divergent selection on chemical production in invasive plants may be critical in regulating herbivore performances and novel AG and BG herbivore communities in new environments.
Khatoon, Amana; Rehman, Shafiq; Hiraga, Susumu; Makino, Takahiro; Komatsu, Setsuko
2012-10-22
Flooding is one of the severe environmental factors which impair growth and yield in soybean plant. To investigate the organ specific response mechanism of soybean under flooding stress, changes in protein species were analyzed using a proteomics approach. Two-day-old soybeans were subjected to flooding for 5 days. Proteins were extracted from root, hypocotyl and leaf, and separated by two-dimensional polyacrylamide gel electrophoresis. In root, hypocotyl and leaf, 51, 66 and 51 protein species were significantly changed, respectively, under flooding stress. In root, metabolism related proteins were increased; however these proteins were decreased in hypocotyl and leaf. In all 3 organs, cytoplasm localized proteins were decreased, and leaf chloroplastic proteins were also decreased. Isoflavone reductase was commonly decreased at protein level in all 3 organs; however, mRNA of isoflavone reductase gene was up-regulated in leaf under flooding stress. Biophoton emission was increased in all 3 organs under flooding stress. The up-regulation of isoflavone reductase gene at transcript level; while decreased abundance at protein level indicated that flooding stress affected the mRNA translation to proteins. These results suggest that concurrence in expression of isoflavone reductase gene at mRNA and protein level along with imbalance in other disease/defense and metabolism related proteins might lead to impaired growth of root, hypocotyl and leaf of soybean seedlings under flooding stress. Copyright © 2012 Elsevier B.V. All rights reserved.
Olsen, Jacob T; Caudle, Keri L; Johnson, Loretta C; Baer, Sara G; Maricle, Brian R
2013-10-01
Phenotypes of two Andropogon gerardii subspecies, big bluestem and sand bluestem, vary throughout the prairie ecosystem of North America. This study sought to determine the role of genetics and environment in driving adaptive variation of leaf structure in big bluestem and sand bluestem. • Four populations of big bluestem and one population of sand bluestem were planted in common gardens at four sites across a precipitation gradient from western Kansas to southern Illinois. Internal leaf structure and trichome density of A. gerardii were examined by light microscopy to separate genetic and environmentally controlled traits. Leaf thickness, midrib thickness, bulliform cells, interveinal distance, vein size, and trichome density were quantified. • At all planting sites, sand bluestem and the xeric population of A. gerardii had thicker leaves and fewer bulliform cells compared with mesic populations. Environment and genetic source population were both influential for leaf anatomy. Leaves from plants grown in mesic sites (Carbondale, Illinois and Manhattan, Kansas) had thicker midribs, larger veins, fewer trichomes, and a greater proportion of bulliform cells compared to plants grown in drier sites (Colby and Hays, Kansas). • Water availability has driven adaptive variation in leaf structure in populations of A. gerardii, particularly between sand bluestem and big bluestem. Genetically based differences in leaves of A. gerardii indicate adaptive variation and evolutionary forces differentiating sand bluestem from big bluestem. Environmental responses of A. gerardii leaves suggest an ability to adjust to drought, even in populations adapted to mesic home environments.
Juniperus phoenicea var. turbinata (Guss.) Parl. Leaf Essential Oil Variability in the Balkans.
Rajčević, Nemanja F; Labus, Marina G; Dodoš, Tanja Z; Novaković, Jelica J; Marin, Petar D
2018-06-15
In the present work leaf essential oil from 97 individuals of Juniperus phoenicea var. turbinata (GUSS.) PARL. from the Balkan Peninsula was analysed. The essential oil was dominated by monoterpene hydrocarbons (45.5 - 71.8%), of which α-pinene was the most abundant in almost all of the samples (38.2 - 55.8%). Several other monoterpenes and sesquiterpenes were also present in relatively high abundances in samples such as myrcene, δ-3-carene, ß-phellandrene, α-terpinyl acetate, (E)-caryophyllene and germacrene D. Multivariate statistical analysis suggested the existence of three possible chemotypes based on the abundance of the four components. Even though the intrapopulation variability was high, discriminant analysis (DA) was able to separate populations. DA showed high separation between western and eastern populations but also grouped geographically closer populations along the west Balkan shoreline. The potential influence of the climate on the composition of the essential oil was also studied. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Kutcherov, Dmitry
2015-12-01
Females of leaf beetles and many other herbivorous insects lay eggs in coherent batches. Hatchlings emerge more or less simultaneously and often prey on their late-hatching clutchmates. It is not certain, however, whether this synchrony of hatching is a mere by-product of cannibalism or whether an additional synchronizing factor exists. The following simple experiment was aimed at determining the causal relationship between cannibalism and simultaneous larval emergence. Egg clutches of the dock leaf beetle Gastrophysa viridula were split into two halves. These halves were either kept as coherent groups in two separate dishes or, alternatively, only one half remained whole, whereas the other one was divided into single eggs, each of which was incubated in a separate dish. Halving of a clutch into coherent groups only slightly disrupted the synchrony of emergence. The consequence of individual isolation was more dramatic. Half-clutches consisting of disconnected solitary eggs required almost twice as much time for complete emergence of all larvae, which was significantly more than cannibalism as a sole synchronizing factor might explain. Moreover, survival rates were the same in coherent half-clutches (in the presence of cannibalism) and among isolated individuals. This group effect and the small contribution of cannibalism suggest the existence of an additional synchronizing factor. Possible mechanisms underpinning this phenomenon are discussed. Copyright © 2015 Elsevier GmbH. All rights reserved.
Emulation of the Active Immune Response in a Computer Network
2009-01-15
the Code Red worm propagated faster than the Melissa virus in 1999 and much faster than Morris’ worm in 1988. In the case of the Code Red worm, only...report to AFRL on contract #30602-01-0509, Binghamton NY, 2002, 2. Skormin, V.A., Delgado-Frias, J.G., McGee, D.L., Giordano , J.V., Popyack, L.J...V., Delgado-Frias J., McGee D., Giordano J., Popyack L.. Tarakanov A., "BASIS: A Biological Approach to System Information Security," ^2
Libertin, Claudia R; Reza, Mohammed; Peterson, Joy H; Lewis, Jason; Hata, D Jane
2017-04-01
AbstractWe describe a case of human infection with Gongylonema pulchrum acquired in southeast Georgia. The patient presented with intermittent yet persistent nausea and vomiting for months. This case describes the need for extraction of worms on two occasions each followed by courses of albendazole treatment. Gongylonema pulchrum infections with high worm burden may relapse after extraction of the worm and a 3-day short course of albendazole therapy. Longer courses of albendazole may be indicated in selected circumstances.
Hydrolytic degradation of poly(ethylene oxide)-block-polycaprolactone worm micelles.
Geng, Yan; Discher, Dennis E
2005-09-21
Spherical micelles and nanoparticles made with degradable polymers have been of great interest for therapeutic application, but degradation-induced changes in a spherical morphology can be subtle and mechanism/kinetics appears poorly understood. Here, we report the first preparation of giant and flexible worm micelles self-assembled from degradable copolymer poly(ethylene oxide)-block-polycaprolactone. Such worm micelles spontaneously shorten to generate spherical micelles, triggered by polycaprolactone hydrolysis, with distinct mechanism and kinetics from that which occurs in bulk material.
Code of Federal Regulations, 2010 CFR
2010-01-01
..., broken skins which are not healed, worms, worm holes, and free from injury caused by bruises, growth cracks, hail, sunburn, sprayburn, scab, bacterial spot, scale, split pit, scars, russeting, other disease...
Code of Federal Regulations, 2012 CFR
2012-01-01
..., broken skins which are not healed, worms, worm holes, and free from injury caused by bruises, growth cracks, hail, sunburn, sprayburn, scab, bacterial spot, scale, split pit, scars, russeting, other disease...
Code of Federal Regulations, 2011 CFR
2011-01-01
..., broken skins which are not healed, worms, worm holes, and free from injury caused by bruises, growth cracks, hail, sunburn, sprayburn, scab, bacterial spot, scale, split pit, scars, russeting, other disease...
Ali, Shaheen Jafri; Rajini, Padmanabhan Sharda
2012-12-01
Positive correlations have been suggested between usage of pesticides and the incidence of Parkinson's disease (PD) through epidemiological as well as few experimental evidences. Organophosphorus insecticides (OPI), which are extensively used in agricultural and household insect control, have been the subject of increasing concern in the past decades due to their neurotoxic potential. However, very few studies have demonstrated the potentials of OPI to induce features of PD in model organisms. In the present study, Caenorhabditis elegans was selected as the model organism to evaluate the potential of monocrotophos (MCP), an OPI, to elicit dopaminergic features of Parkinson's disease in terms of dopamine content, basic movement and integrity of dopaminergic neurons along with its effect on acetylcholinesterase (AChE) activity and life span. All the responses elicited by MCP were compared with that elicited by 1-methyl-4-phenyl- 1, 2, 3, 6-tetrahydropyridine (MPTP) in both N2 and BZ555 worms. N2 worms were exposed to varying concentrations of MCP (50, 100 and 200 μM) or MPTP (200, 300 and 400 μM) for 48 hours and locomotory rate, as measured by the number of body bends made in 20 seconds, was enumerated. Worms subjected to the same dose paradigms were also analyzed for the dopamine content by HPLC. The results indicated a significant reduction in the dopamine levels in the worms that were treated with MCP/MPTP and this correlated with the changes in locomotion compared to untreated worms. Worms treated with MCP also exhibited significant reduction in AChE activity. Both MPTP and MCP caused a marked reduction in life span in the worms. Transgenic worms (BZ555, which has GFP tagged to its 8 dopaminergic neurons) exposed to MCP and MPTP at the above concentrations showed a dose-dependent reduction in the number of green pixels in CEP and ADE neurons which also correlated with the neurodegeneration as visualized by decreased fluorescence in photomicrographs. Taken together, our data demonstrate that low levels of MCP elicits dopaminergic features of PD in C. elegans.
Rainbow, P.S.; Poirier, L.; Smith, B.D.; Brix, K.V.; Luoma, S.N.
2006-01-01
The chemical form of accumulated trace metal in prey is important in controlling the bioavailataility of dietary metal to a predator. This study investigated the trophic transfer of radiolabelled Ag, Cd and Zn from the polychaete worm Nereis diversicolor to the decapod crustacean Palaemonetes varians. We used 2 populations of worms with different proportions of accumulated metals in different subcellular fractions as prey, and loaded the worms with radiolabelled metals either from sediment or from solution. Accumulated radiolabelled metals were fractionated into 5 components : metal-rich granules (MRG), cellular debris, organelles, metallothionein-like proteins (MTLP), and other (heat-sensitive) proteins (HSP). Assimilation efficiencies (AE) of the metals by P. varians were measured from the 4 categories of prey (i.e. 2 populations, radiolabelled from sediment or solution). There were significant differences for each metal between the AEs from the different prey categories, confirming that origin of prey and route of uptake of accumulated trace metal will cause intraspecific differences in subsequent metal assimilation. Correlations were sought between AEs and selected fractions or combinations of fractions of metals in the prey-MRG, Trophically Available Metal (TAM = MTLP + HSP + organelles) and total protein (MTLP + HSP). TAM explained 28% of the variance in AEs for Ag, but no consistent relationships emerged between AEs and TAM or total protein when the metals were considered separately. AEs did, however, show significant positive regressions with both TAM and total protein when the 3 metals were considered together, explaining only about 21 % of the variance in each case. A significant negative relationship was observed between MRG and AE for all metals combined. The predator (P. varians) can assimilate dietary metal from a range of the fractions binding metals in the prey (N. diversicolor), with different assimilation efficiencies summated across these fractions. TAM and/or total protein may represent an approximate minimum for trophic availability but neither of these alone is a fully accurate predictor. ?? Inter-Research 2006.
Anthelmintic Potential of Thymoquinone and Curcumin on Fasciola gigantica
Ullah, Rizwan; Rehman, Abdur; Zafeer, Mohd Faraz; Rehman, Lubna; Khan, Yasir A.; Khan, M. A. Hannan; Khan, Shahper N.; Khan, Asad U.; Abidi, S. M. A.
2017-01-01
Fasciolosis an economically important global disease of ruminants in the temperate and tropical regions, caused by Fasciola hepatica and F. gigantica, respectively, also poses a potential zoonotic threat. In India alone it causes huge losses to stakeholders. Anthelmintics including triclabendazole have been used to control this menace but the emerging resistance against the available compounds necessitates identification of novel and alternative therapeutic measures involving plant derived natural compounds for their anthelmintic potential. Thymoquinone (T) and curcumin (C), the active ingredients of Nigella sativa and Curcuma longa respectively have been used as antiparasitic agents but the information on their flukicidal effect is very limited. Adult flukes of F. gigantica were in vitro exposed to different concentrations of thymoquinone and curcumin separately for 3h at 37+ 1°C. A significant (p<0.05) reduction in the worm motility at 60 μM concentration of both T and C was observed though all the worms remained alive after 3h exposure, whereas the effect on egg shedding was statistically insignificant. Pronounced tegumental disruptions and erosion of spines in the posterior region and around the acetabulum was evident. A significant (p<0.05) decrease in glutathione-S-transferase and superoxide dismutase activity and reduced glutathione (GSH) level was observed, while protein carbonylation increased differentially. A significant inhibition of CathepsinL (CatL) gene expression in thymoquinone treated worms was also evident. Further, in silico molecular docking of T and C with CatL revealed a stronger interaction of curcumin with the involvement of higher number of amino acids as compared to thymoquinone that could be more effective in inhibiting the antioxidant enzymes of F. gigantica. It is concluded that both the compounds understudy will decrease the detoxification ability of F. gigantica, while inhibition of CatL will significantly affect their virulence potential. Thus, both thymoquinone and curcumin appeared to be promising anthelmintic compounds for further investigations. PMID:28152102
Anthelmintic Potential of Thymoquinone and Curcumin on Fasciola gigantica.
Ullah, Rizwan; Rehman, Abdur; Zafeer, Mohd Faraz; Rehman, Lubna; Khan, Yasir A; Khan, M A Hannan; Khan, Shahper N; Khan, Asad U; Abidi, S M A
2017-01-01
Fasciolosis an economically important global disease of ruminants in the temperate and tropical regions, caused by Fasciola hepatica and F. gigantica, respectively, also poses a potential zoonotic threat. In India alone it causes huge losses to stakeholders. Anthelmintics including triclabendazole have been used to control this menace but the emerging resistance against the available compounds necessitates identification of novel and alternative therapeutic measures involving plant derived natural compounds for their anthelmintic potential. Thymoquinone (T) and curcumin (C), the active ingredients of Nigella sativa and Curcuma longa respectively have been used as antiparasitic agents but the information on their flukicidal effect is very limited. Adult flukes of F. gigantica were in vitro exposed to different concentrations of thymoquinone and curcumin separately for 3h at 37+ 1°C. A significant (p<0.05) reduction in the worm motility at 60 μM concentration of both T and C was observed though all the worms remained alive after 3h exposure, whereas the effect on egg shedding was statistically insignificant. Pronounced tegumental disruptions and erosion of spines in the posterior region and around the acetabulum was evident. A significant (p<0.05) decrease in glutathione-S-transferase and superoxide dismutase activity and reduced glutathione (GSH) level was observed, while protein carbonylation increased differentially. A significant inhibition of CathepsinL (CatL) gene expression in thymoquinone treated worms was also evident. Further, in silico molecular docking of T and C with CatL revealed a stronger interaction of curcumin with the involvement of higher number of amino acids as compared to thymoquinone that could be more effective in inhibiting the antioxidant enzymes of F. gigantica. It is concluded that both the compounds understudy will decrease the detoxification ability of F. gigantica, while inhibition of CatL will significantly affect their virulence potential. Thus, both thymoquinone and curcumin appeared to be promising anthelmintic compounds for further investigations.
Particle removal by vegetation: comparison in a forest and a wetland.
Liu, Jiakai; Zhai, Jiexiu; Zhu, Lijuan; Yang, Yilian; Liu, Jiatong; Zhang, Zhenming
2017-01-01
Vegetation collection is one of the most effective scavenging methods but relevant studies are limited. It can be described by some abstract parameters such as collection rates and deposition fluxes within the canopy. In order to estimate the dry deposition within the canopy of particular matters (PMs) in Beijing, a highly particle-polluted city, and reveal the PM pollution-removal abilities of plants in wetlands and forests, concentration and meteorological data were collected during the daytime in an artificial forest and a wetland in the Olympic Park in Beijing. The dry depositions within the canopy and vegetation collection rates were calculated by a well-developed model and validated by measured deposition fluxes in 11 random experiment days. The experiment year was divided into three plant growth stages based on canopy density, and the day was divided into four different times. Two heights, 10 and 1.5 m, were defined in the forest while in the wetland, 0.5 and 1.5 m were defined. The results showed that in Beijing, the most severe pollution by PMs occurs in the non-leaf stage (NS), and the full-leaf stage (FS) is the cleanest stage. In NS, namely winter, more fossil fuel was used for worms in Beijing and peripheral areas and this might be the reason for the serious pollution condition. Within the canopy, PM deposition fluxes in the wetland are more than those in the forest, but the vegetation collection rates of the forest are higher. The lower temperature conditions led to more dry deposition, and the larger canopy contributed to the higher collection rates. During the daytime, over the year, the deposition of PM 10 in three plant growth stages is NS ≥ half-leaf stages (HS) ≥ FS, whereas the deposition of PM 2.5 is NS ≥ FS ≥ HS, and during the daytime, the maximum deposition fluxes occur in 6:00-9:00 in the wetland while the minimum deposition values occur in 15:00-18:00. This phenomenon was related to the temporal variation of particle concentration.
Low frequency acoustic properties of Posidonia oceanica seagrass leaf blades
Johnson, Jay R.; Venegas, Gabriel R.; Wilson, Preston S.; Hermand, Jean-Pierre
2017-01-01
The acoustics of seagrass meadows impacts naval and oceanographic sonar applications. To study this environment, a one-dimensional resonator was used to assess the low-frequency (1–5 kHz) acoustic response of the leaf blades of the Mediterranean seagrass Posidonia oceanica in water. Three separate collections of plants from Crete, Greece, and Sicily, Italy were investigated. A high consistency in effective sound speed was observed within each collection while a strong variability was observed between different collections. Average size, mass, and epiphytic coverage within each collection were quantified, and discoloration and stiffness are discussed qualitatively with respect to the observed acoustic variability. PMID:28618796
21 CFR 520.1198 - Ivermectin and praziquantel paste.
Code of Federal Regulations, 2014 CFR
2014-04-01
...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral...
21 CFR 520.1198 - Ivermectin and praziquantel paste.
Code of Federal Regulations, 2013 CFR
2013-04-01
...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral...
Code of Federal Regulations, 2010 CFR
2010-01-01
... from decay, broken skins which are not healed, worms, worm holes, and free from serious damage caused by bruises, growth cracks, hail, sunburn, sprayburn, scab, bacterial spot, scale, split pit, scars...
Code of Federal Regulations, 2010 CFR
2010-01-01
... which are mature, handpicked, firm, well formed, free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and from damage caused by broken skins, limbrubs, sprayburn, sunburn...
Code of Federal Regulations, 2011 CFR
2011-01-01
... which are mature, handpicked, firm, well formed, free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and from damage caused by broken skins, limbrubs, sprayburn, sunburn...
7 CFR 51.1280 - Serious damage.
Code of Federal Regulations, 2014 CFR
2014-01-01
... shall be considered under the definition of russeting. (5) Insects: (i) Worm holes. More than three... worm injury which affects an aggregate area of more than three-fourths inch in diameter or which...
7 CFR 51.1280 - Serious damage.
Code of Federal Regulations, 2013 CFR
2013-01-01
... shall be considered under the definition of russeting. (5) Insects: (i) Worm holes. More than three... worm injury which affects an aggregate area of more than three-fourths inch in diameter or which...
7 CFR 51.1323 - Serious damage.
Code of Federal Regulations, 2012 CFR
2012-01-01
... under the definition of russeting. (7) Insects: (i) Worm holes. More than three healed codling moth... insect stings affecting the appearance to an equal extent. 2 (ii) Blister mite or canker worm injury...
Code of Federal Regulations, 2012 CFR
2012-01-01
... which are mature, handpicked, firm, well formed, free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and from damage caused by broken skins, limbrubs, sprayburn, sunburn...
21 CFR 520.1198 - Ivermectin and praziquantel paste.
Code of Federal Regulations, 2011 CFR
2011-04-01
...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral...
Mayo Marques, Marcia Ortiz; Maria Rodrigues, Tatiane
2017-01-01
Abstract Herbivory can induce several structural and functional alterations in the plant secretory system. Glandular trichomes are the main sites of production of volatile organic compounds (VOCs) with several chemical properties in Lamiaceae species. Ocimum species usually have three morphotypes of glandular trichomes (morphotype I is peltate and has a wide four-celled head; morphotype II is capitate and has a unicellular head; and morphotype III is capitate with a bicellular head) which produce a great amount of terpenes, although other chemical categories of substances are also produced. Despite the abundance of trichomes producing important anti-herbivory components in their leaves, the association between Ocimum species and leaf-cutter ants has been commonly registered in Brazil. We investigated the effect of leaf-cutter ant attack on the density of the glandular trichomes and on the chemistry of the VOCs released from leaves of O. gratissimum. Plants were subjected to Acromyrmex rugosus attack until 90 % of leaves were removed. After 40 days from the leaf-cutter attack, both treatments were sampled. The glandular trichome density was analysed by scanning electron microscopy. The VOCs were extracted utilizing headspace solid-phase microextraction (HS-SPME) technique and analysed by gas chromatography. Generally, the density of glandular trichomes increased in the adaxial leaf surface of the attacked plants. However, we bring novelties on this topic since we analysed the density of each morphotype separately. The morphotype I decreased in the abaxial leaf surface, and increased in the adaxial leaf surface; the morphotype II increased in both leaf surfaces; and the morphotype III decreased in the abaxial leaf surface and remained constant in the adaxial leaf surface of attacked plants. In leaves of attacked plants, the (Z)-β-ocimene increased by 50 %, the α-selinene by 13 % and the germacrene D by 126 %, whereas the eugenol decreased by 70 %. Our data point to a differential response of each glandular morphotype in O. gratissimum and are consistent with the idea of a compartmentalization of functions among the different glandular morphotypes in the plant defence against environmental factors. PMID:29218139
Stoepler, Teresa M; Lill, John T
2013-10-01
A variety of ecological factors influence host use by parasitoids, including both abiotic and biotic factors. Light environment is one important abiotic parameter that differs among habitats and influences a suite of plant nutritional and resistance traits that in turn affect herbivore performance. However, the extent to which these bottom-up effects "cascade up" to affect higher trophic levels and the relative importance of direct and indirect effects of sunlight on tritrophic interactions are unclear. The objective of this study was to test how light environment (light gap vs. shaded forest understory) and leaf type (sun vs. shade leaves) affect the performance and incidence of parasitism of two species of moth larvae, Euclea delphinii and Acharia stimulea (Limacodidae). We manipulated the leaf phenotype of potted white oak saplings by growing them in either full sun or full shade throughout leaf expansion to produce sun and shade leaves, respectively. These saplings were then placed in light gap and adjacent shaded understory habitats in the forest in a full-factorial design, and stocked with sentinel larvae that were exposed to parasitism ("exposed" experiments). We reared additional larvae in sleeve cages (protected from parasitism) to isolate light environment and leaf phenotype treatment effects on larval performance in the absence of enemies ("bagged" experiments). In the exposed experiments, light environment strongly affected the likelihood of parasitism, while leaf phenotype did not. Euclea delphinii larvae were up to 6.6 times more likely to be parasitized in light gaps than in shaded understory habitats. This pattern was consistent for both tachinid fly and wasp parasitoids across two separate experiments. However, the larval performance of both species in the bagged experiments was maximized in the shade-habitat/sun-leaf treatment, a habitat/leaf-type combination that occurs infrequently in nature. Taken together, our results suggest that the direct effects of light environment on the incidence of parasitism supersede any indirect effects resulting from altered leaf quality and reveal inherent ecological trade-offs for herbivores confronted with choosing between sunny (high leaf quality, harsh environment, high parasitism) and shaded (reduced leaf quality less harsh environment, reduced parasitism) habitats.
Kim, Mi Jung; Jin, Jingjing; Zheng, Junshi; Wong, Limsoon; Chua, Nam-Hai; Jang, In-Cheol
2015-12-01
Stevia (Stevia rebaudiana) produces not only a group of diterpenoid glycosides known as steviol glycosides (SGs), but also other labdane-type diterpenoids that may be spatially separated from SGs. However, their biosynthetic routes and spatial distribution in leaf tissues have not yet been elucidated. Here, we integrate metabolome and transcriptome analyses of Stevia to explore the biosynthetic capacity of leaf tissues for diterpenoid metabolism. Tissue-specific chemical analyses confirmed that SGs were accumulated in leaf cells but not in trichomes. On the other hand, Stevia leaf trichomes stored other labdane-type diterpenoids such as oxomanoyl oxide and agatholic acid. RNA sequencing analyses from two different tissues of Stevia provided a comprehensive overview of dynamic metabolic activities in trichomes and leaf without trichomes. These metabolite-guided transcriptomics and phylogenetic and gene expression analyses clearly identified specific gene members encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate pathway and the biosynthesis of steviol or other labdane-type diterpenoids. Additionally, our RNA sequencing analysis uncovered copalyl diphosphate synthase (SrCPS) and kaurene synthase1 (SrKS1) homologs, SrCPS2 and KS-like (SrKSL), which were specifically expressed in trichomes. In vitro and in planta assays showed that unlike SrCPS and SrKS1, SrCPS2 synthesized labda-13-en-8-ol diphosphate and successively catalyzed the formation of manoyl oxide and epi-manoyl oxide in combination with SrKSL. Our findings suggest that Stevia may have evolved to use distinct metabolic pathways to avoid metabolic interferences in leaf tissues for efficient production of diverse secondary metabolites. © 2015 American Society of Plant Biologists. All Rights Reserved.
NASA Astrophysics Data System (ADS)
Mackay, D. S.; Ewers, B. E.; Kruger, E. L.
2006-12-01
Phenological variations impact water and carbon fluxes, as evidenced by the large interannual variability of net ecosystem exchange of carbon dioxide and evapotranspiration (ET). In northern Wisconsin we observed daily variations of canopy transpiration from hardwoods from 1.0 to 1.7 mm/day during the leaf unfolding period and 1.7 to 2.6 mm/day with leaves fully out. Correlations between such flux rates and phenology have not been extensively tested and mechanistic connections are in their infancy. Some data suggest that stomatal conductance and photosynthesis increases up to full expansion. Moreover, in conifers, the interaction of phenology and physiology is more complicated than in deciduous trees because needles are retained for several years. Using inverse modeling with a coupled photosynthesis-transpiration model we estimated reference canopy stomatal conductance, Gsref, for red pine (Pinus resinosa), and Gsref and leaf area index, L, for trembling aspen (Populus tremuloides), using 30-min continuous sap flux data spanning a period from just prior to the start of leaf expansion to just after leaf senescence. The red pine showed Gsref ramp up from 105 to 179 mmol m-2 leaf s-1, which represented a 37 to 50 percent increase in Gsref after accounting for maximum possible changes in L. After full leaf out, the trembling aspen were almost immediately defoliated, and then reflushed after three weeks. Model estimates of L reflected this pattern and were consistent with measurements. However, Gsref never exceeded 45 mmol m-2 s-1 prior to defoliation, but peaked at 112 mmol m-2 s-1 after reflushing. These results support the need for further work that aims to separate phenology and physiology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tsai, Baolong.
Absorption, translocation, distribution, exudation, and guttation of {sup 14}C-glyphosate in water hyacinth (Eichhornia crassipes) were studied. Glyphosphate entered the plant by foliage and solution treatment. Plants were harvested and separated into the following parts: treated leaf blade, treated leaf petiole, young leaf blade, young leaf petiole, old leak blade, old leaf petiole, and root. Each part was extracted with methanol. Treated leaves, which exist only in foliage treatment, were washed with water and chloroform to remove the glyphosate residues. All {sup 14}C counting was made by liquid scintillation spectrometry. Autoradiography was used to locate {sup 14}C-glyphosate after foliage treatment. Resultsmore » indicated that glyphosate can be absorbed from the leaf surface and translocated rapidly through phloem tissues into the whole plant body. The roots of water hyacinth absorbed glyphosate without vertical transport. Guttation of glyphosate occurred in treated leaf tips. Exudation of glyphosate from roots of water hyacinth occurred within 8 hr after foliage treatment. Chlorella vulgaris, Chlamydomonas reihardii, Anabaena cylindrica, and Chroococcus turgidus were used to explore the physiological and biochemical effects of glyphosate on algae. Spectrophotometric assays were performed for algal growth, chlorophyll, carotenoids, phycobiliprotein, carbohydrate, and protein. TLC procedures and an image analyzer were used to detect the metabolites of glyphosate inside algal cells. The common visible symptom of glyphosate toxicity in all algal cells were bleaching effect and reduction of contents of carbohydrate, protein, and pigments. The results highly suggested that glyphosate injured the algal cells by destruction of photosynthetic pigments and resulted in lowering the contents of carbohydrate and protein in algal cells.« less
Tosens, Tiina
2012-01-01
In sclerophylls, photosynthesis is particularly strongly limited by mesophyll diffusion resistance from substomatal cavities to chloroplasts (r m), but the controls on diffusion limits by integral leaf variables such as leaf thickness, density, and dry mass per unit area and by the individual steps along the diffusion pathway are imperfectly understood. To gain insight into the determinants of r m in leaves with varying structure, the full CO2 physical diffusion pathway was analysed in 32 Australian species sampled from sites contrasting in soil nutrients and rainfall, and having leaf structures from mesophytic to strongly sclerophyllous. r m was estimated based on combined measurements of gas exchange and chlorophyll fluorescence. In addition, r m was modelled on the basis of detailed anatomical measurements to separate the importance of different serial resistances affecting CO2 diffusion into chloroplasts. The strongest sources of variation in r m were S c/S, the exposed surface area of chloroplasts per unit leaf area, and mesophyll cell wall thickness, t cw. The strong correlation of r m with t cw could not be explained by cell wall thickness alone, and most likely arose from a further effect of cell wall porosity. The CO2 drawdown from intercellular spaces to chloroplasts was positively correlated with t cw, suggesting enhanced diffusional limitations in leaves with thicker cell walls. Leaf thickness and density were poorly correlated with S c/S, indicating that widely varying combinations of leaf anatomical traits occur at given values of leaf integrated traits, and suggesting that detailed anatomical studies are needed to predict r m for any given species. PMID:22888123
Autumnal leaf senescence in Miscanthus × giganteus and leaf [N] differ by stand age
Boersma, Nicholas N.; Dohleman, Frank G.; Miguez, Fernando E.; Heaton, Emily A.
2015-01-01
Poor first winter survival in Miscanthus × giganteus has been anecdotally attributed to incomplete first autumn senescence, but these assessments never paired first-year with older M. × giganteus in side-by-side trials to separate the effect of weather from stand age. Here CO2 assimilation rate (A), photosystem II efficiency (ΦPSII), and leaf N concentration ([N]) were used to directly compare senescence in first, second, and third-year stands of M. × giganteus. Three M. × giganteus fields were planted with eight plots, one field each in 2009, 2010, and 2011. To quantify autumnal leaf senescence of plants within each stand age, photosynthetic and leaf [N] measurements were made twice weekly from early September until a killing frost. Following chilling events (daily temperature averages below 10 °C), photosynthetic rates in first year plants rebounded to a greater degree than those in second- and third-year plants. By the end of the growing season, first-year M. × giganteus had A and ΦPSII rates up to 4 times greater than third-year M. × giganteus, while leaf [N] was up to 2.4 times greater. The increased photosynthetic capability and leaf N status in first-year M. × giganteus suggests that the photosynthetic apparatus was not dismantled before a killing frost, thus potentially limiting nutrient translocation, and may explain why young M. × giganteus stands do not survive winter when older stands do. Because previous senescence research has primarily focused on annual or woody species, our results suggest that M. × giganteus may be an interesting herbaceous perennial system to investigate the interactive effects of plant ageing and nutrient status on senescence and may highlight management strategies that could potentially increase winter survival rates in first-year stands. PMID:25873682
Vivian, Lyndsey M; Cary, Geoffrey J
2012-01-01
Resprouting and seed recruitment are important ways in which plants respond to fire. However, the investments a plant makes into ensuring the success of post-fire resprouting or seedling recruitment can result in trade-offs that are manifested in a range of co-occurring morphological, life history and physiological traits. Relationships between fire-response strategies and other traits have been widely examined in fire-prone Mediterranean-type climates. In this paper, we aim to determine whether shrubs growing in a non-Mediterranean climate region exhibit relationships between their fire-response strategy and leaf traits. Field surveys were used to classify species into fire-response types. We then compared specific leaf area, leaf dry-matter content, leaf width, leaf nitrogen and carbon to nitrogen ratios between (a) obligate seeders and all other resprouters, and (b) obligate seeders, facultative resprouters and obligate resprouters. Leaf traits only varied between fire-response types when we considered facultative resprouters as a separate group to obligate resprouters, as observed after a large landscape-scale fire. We found no differences between obligate seeders and obligate resprouters, nor between obligate seeders and resprouters considered as one group. The results suggest that facultative resprouters may require a strategy of rapid resource acquisition and fast growth in order to compete with species that either resprout, or recruit from seed. However, the overall lack of difference between obligate seeders and obligate resprouters suggests that environmental factors are exerting similar effects on species' ecological strategies, irrespective of the constraints and trade-offs that may be associated with obligate seeding and obligate resprouting. These results highlight the limits to trait co-occurrences across different ecosystems and the difficulty in identifying global-scale relationships amongst traits.
Vivian, Lyndsey M.; Cary, Geoffrey J.
2012-01-01
Background and Aims Resprouting and seed recruitment are important ways in which plants respond to fire. However, the investments a plant makes into ensuring the success of post-fire resprouting or seedling recruitment can result in trade-offs that are manifested in a range of co-occurring morphological, life history and physiological traits. Relationships between fire-response strategies and other traits have been widely examined in fire-prone Mediterranean-type climates. In this paper, we aim to determine whether shrubs growing in a non-Mediterranean climate region exhibit relationships between their fire-response strategy and leaf traits. Methods Field surveys were used to classify species into fire-response types. We then compared specific leaf area, leaf dry-matter content, leaf width, leaf nitrogen and carbon to nitrogen ratios between (a) obligate seeders and all other resprouters, and (b) obligate seeders, facultative resprouters and obligate resprouters. Key Results Leaf traits only varied between fire-response types when we considered facultative resprouters as a separate group to obligate resprouters, as observed after a large landscape-scale fire. We found no differences between obligate seeders and obligate resprouters, nor between obligate seeders and resprouters considered as one group. Conclusions The results suggest that facultative resprouters may require a strategy of rapid resource acquisition and fast growth in order to compete with species that either resprout, or recruit from seed. However, the overall lack of difference between obligate seeders and obligate resprouters suggests that environmental factors are exerting similar effects on species' ecological strategies, irrespective of the constraints and trade-offs that may be associated with obligate seeding and obligate resprouting. These results highlight the limits to trait co-occurrences across different ecosystems and the difficulty in identifying global-scale relationships amongst traits. PMID:21994052
Code of Federal Regulations, 2010 CFR
2010-01-01
..., broken skins which are not healed, worms, worm holes, and free from injury caused by split pit and free from damage caused by bruises, growth cracks, hail, sunburn, sprayburn, scab, bacterial spot, scale...
Code of Federal Regulations, 2011 CFR
2011-01-01
... which are mature, handpicked, firm, not seriously deformed, free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and free from serious damage by any other cause. Unless...
Code of Federal Regulations, 2010 CFR
2010-01-01
... which are mature, handpicked, firm, not seriously deformed, free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and free from serious damage by any other cause. Unless...
Code of Federal Regulations, 2014 CFR
2014-01-01
... badly misshapen, which are clean and free from decay, broken skins which are not healed, worms, worm holes, and free from serious damage caused by bruises, growth cracks, hail, sunburn, sprayburn, scab...
Code of Federal Regulations, 2013 CFR
2013-01-01
... badly misshapen, which are clean and free from decay, broken skins which are not healed, worms, worm holes, and free from serious damage caused by bruises, growth cracks, hail, sunburn, sprayburn, scab...
Code of Federal Regulations, 2012 CFR
2012-01-01
... which are mature, handpicked, firm, not seriously deformed, free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and free from serious damage by any other cause. Unless...
Waldrop, Thomas B.; Densmore, Christine; Blazer, Vicki; Smith, Dave; Schill, Bane; Schill, B.; Waldrop, T.; Blazer, V.
1999-01-01
Whirling disease is caused by Myxobolus cerebralis and requires an intermediate oligochaete host identified as Tubifex tubifex (Wolf, Markiw, and Hiltunen, 1986). M. cerebralis spores ingested by the tubifex worms develop into triactinomyxons (tams) that are eventually released into the water column to infect salmonid fish. There may be many environmental parameters, biotic or abiotic, that may affect the development of waterborne tams in eastern tubifex worms. This study will focus on one of those environmental parameters, total water hardness. Total water hardness is defined as the concentration of calcium and magnesium in a water sample expressed in milligrams per liter of equivalent CACO3 (Boyd, 1990). This study will address whether different levels of water hardness affect the development and production of tams released by infected tubifex worms.
Roussilhon, Christian; Brasseur, Philippe; Agnamey, Patrice; Pérignon, Jean-Louis; Druilhe, Pierre
2010-01-01
Background Former studies have pointed to a monocyte-dependant effect of antibodies in protection against malaria and thereby to cytophilic antibodies IgG1 and IgG3, which trigger monocyte receptors. Field investigations have further documented that a switch from non-cytophilic to cytophilic classes of antimalarial antibodies was associated with protection. The hypothesis that the non-cytophilic isotype imbalance could be related to concomittant helminthic infections was supported by several interventions and case-control studies. Methods and Findings We investigated here the hypothesis that the delayed acquisition of immunity to malaria could be related to a worm-induced Th2 drive on antimalarial immune responses. IgG1 to IgG4 responses against 6 different parasite-derived antigens were analyzed in sera from 203 Senegalese children, half carrying intestinal worms, presenting 421 clinical malaria attacks over 51 months. Results show a significant correlation between the occurrence of malaria attacks, worm carriage (particularly that of hookworms) and a decrease in cytophilic IgG1 and IgG3 responses and an increase in non-cytophilic IgG4 response to the merozoite stage protein 3 (MSP3) vaccine candidate. Conclusion The results confirm the association with protection of anti-MSP3 cytophilic responses, confirm in one additional setting that worms increase malaria morbidity and show a Th2 worm-driven pattern of anti-malarial immune responses. They document why large anthelminthic mass treatments may be worth being assessed as malaria control policies. PMID:20174576
Souza, Joyce G R; Garcia, Juberlan S; Gomes, Ana Paula N; Machado-Silva, José Roberto; Maldonado, Arnaldo
2017-12-01
Echinostoma paraensei (Digenea: Echinostomatidae) lives in the duodenum and bile duct of rodents and is reported as a useful model for studies on the biology of flatworms. Here, we compared the growth and development of pre and post ovigerous worms collected 3, 7, 14 and 21 days post infection from experimentally infected hamster (permissive host) and Wistar rat (less permissive hosts). Linear measurements and ratios were examined by light (morphology and morphometry) and confocal laser scanning microscopy. At day 3, either worm from hamsters or rats were small with poorly developed gonads. At seven day, worms increased in size and morphometric differences between hosts are statistically significant after this time. In addition, adult worms (14 and 21 days of age) harvested from hamster showed developed gonads and vitelline glands laterally distributed on the body, whereas worms from rat showed atrophied reproductive system characterized by underdeveloped vitelline glands and stunted ovary. The worm rate recovery in rat decreased from 29.3% (day 7) to 20.6% (day 14) and 8% (day 21), whilst it remained around 37% in hamster. In conclusion, this is the first appointment demonstrating that low permissiveness influences the reproductive system of echinostome since the immature stages of development. The phenotypic analysis evidenced that hamster provides a more favorable microenvironment for gonads development than rat, confirming golden hamster as a permissive host, whereas Wistar rat is less permissive host. Copyright © 2017 Elsevier Inc. All rights reserved.
Mechanistic insights for block copolymer morphologies: how do worms form vesicles?
Blanazs, Adam; Madsen, Jeppe; Battaglia, Giuseppe; Ryan, Anthony J; Armes, Steven P
2011-10-19
Amphiphilic diblock copolymers composed of two covalently linked, chemically distinct chains can be considered to be biological mimics of cell membrane-forming lipid molecules, but with typically more than an order of magnitude increase in molecular weight. These macromolecular amphiphiles are known to form a wide range of nanostructures (spheres, worms, vesicles, etc.) in solvents that are selective for one of the blocks. However, such self-assembly is usually limited to dilute copolymer solutions (<1%), which is a significant disadvantage for potential commercial applications such as drug delivery and coatings. In principle, this problem can be circumvented by polymerization-induced block copolymer self-assembly. Here we detail the synthesis and subsequent in situ self-assembly of amphiphilic AB diblock copolymers in a one pot concentrated aqueous dispersion polymerization formulation. We show that spherical micelles, wormlike micelles, and vesicles can be predictably and efficiently obtained (within 2 h of polymerization, >99% monomer conversion) at relatively high solids in purely aqueous solution. Furthermore, careful monitoring of the in situ polymerization by transmission electron microscopy reveals various novel intermediate structures (including branched worms, partially coalesced worms, nascent bilayers, "octopi", "jellyfish", and finally pure vesicles) that provide important mechanistic insights regarding the evolution of the particle morphology during the sphere-to-worm and worm-to-vesicle transitions. This environmentally benign approach (which involves no toxic solvents, is conducted at relatively high solids, and requires no additional processing) is readily amenable to industrial scale-up, since it is based on commercially available starting materials.
NASA Astrophysics Data System (ADS)
Barthod, Justine; Rumpel, Cornélia; Paradelo, Remigio; Dignac, Marie-France
2016-12-01
In this study we evaluated CO2 emissions during composting of green wastes with clay and/or biochar in the presence and absence of worms (species of the genus Eisenia), as well as the effect of those amendments on carbon mineralization after application to soil. We added two different doses of clay, biochar or their mixture to pre-composted green wastes and monitored carbon mineralization over 21 days in the absence or presence of worms. The resulting co-composts and vermicomposts were then added to a loamy Cambisol and the CO2 emissions were monitored over 30 days in a laboratory incubation. Our results indicated that the addition of clay or clay/biochar mixture reduced carbon mineralization during co-composting without worms by up to 44 %. In the presence of worms, CO2 emissions during composting increased for all treatments except for the low clay dose. The effect of the amendments on carbon mineralization after addition to soil was small in the short term. Overall, composts increased OM mineralization, whereas vermicomposts had no effect. The presence of biochar reduced OM mineralization in soil with respect to compost and vermicompost without additives, whereas clay reduced mineralization only in the composts. Our study indicates a significant role of the conditions of composting on mineralization in soil. Therefore, the production of a low CO2 emission amendment requires optimization of feedstocks, co-composting agents and worm species.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meharg, A.A.; Shore, R.F.; Broadgate, K.
The toxicity and accumulation of arsenate was determined in the earthworm Lumbricus terrestris in soil from different layers of a forest profile. Toxicity increased fourfold between 2 and 10 d. Edaphic factors (pH, soil organic matter, and depth in soil profile) also affected toxicity with a three fold decrease in the concentration that causes 50% mortality with increasing depth in soil. In a 4-d exposure study, there was no evidence of arsenic bioconcentration in earthworm tissue, although bioaccumulation was occurring. There was a considerable difference in tissue residues between living and dead earthworms, with dead worms having higher concentrations. Thismore » difference was dependent on both soil arsenate concentration and on soil type. Over a wide range of soil arsenate concentrations, earthworm arsenic residues are homeostatically maintained in living worms, but this homeostasis breaks down during death. Alternatively, equilibration with soil residues may occur via accumulation after death. In long-term accumulation studies in soils dosed with a sublethal arsenate concentration, bioconcentration of arsenate did not occur until day 12, after which earthworm concentrations rose steadily above the soil concentration, with residues in worms three fold higher than soil concentrations by the termination of the study. This bioconcentration only occurred in depurated worms over the time period of the study. Initially, depurated worms had lower arsenic concentrations than undepurated until tissue concentrations were equivalent to the soil concentration. Once tissue concentration was greater than soil concentration, depurated worms had higher arsenic residues than undepurated.« less
Pyrosequencing of prey DNA in reptile faeces: analysis of earthworm consumption by slow worms.
Brown, David S; Jarman, Simon N; Symondson, William O C
2012-03-01
Little quantitative ecological information exists on the diets of most invertebrate feeding reptiles, particularly nocturnal or elusive species that are difficult to observe. In the UK and elsewhere, reptiles are legally required to be relocated before land development can proceed, but without knowledge of their dietary requirements, the suitability of receptor sites cannot be known. Here, we tested the ability of non-invasive DNA-based molecular diagnostics (454 pyrosequencing) to analyse reptile diets, with the specific aims of determining which earthworm species are exploited by slow worms (the legless lizard Anguis fragilis) and whether they feed on the deeper-living earthworm species that only come to the surface at night. Slow worm faecal samples from four different habitats were analysed using earthworm-specific PCR primers. We found that 86% of slow worms (N=80) had eaten earthworms. In lowland heath and marshy/acid grassland, Lumbricus rubellus, a surface-dwelling epigeic species, dominated slow worm diet. In two other habitats, riverside pasture and calciferous coarse grassland, diet was dominated by deeper-living anecic and endogeic species. We conclude that all species of earthworm are exploited by these reptiles and lack of specialization allows slow worms to thrive in a wide variety of habitats. Pyrosequencing of prey DNA in faeces showed promise as a practical, rapid and relatively inexpensive means of obtaining detailed and valuable ecological information on the diets of reptiles. © 2011 Blackwell Publishing Ltd.
Transgenic rice expressing the cry2AX1 gene confers resistance to multiple lepidopteran pests.
Chakraborty, M; Reddy, P Sairam; Mustafa, G; Rajesh, G; Narasu, V M Laxmi; Udayasuriyan, V; Rana, Debashis
2016-10-01
A chimeric Bacillus thuringiensis toxin (Bt) gene, cry2AX1was cloned in a bi-selectable marker free binary vector construct. The cry2AX1 gene, driven by the Chrysanthemum rbcS1 promoter, was introduced into JK1044R, the restorer line (Oryza sativa L. ssp. Indica) of a notified commercially grown rice hybrid in India, by Agrobacterium-mediated transformation. Its effect against two major lepidopteran insect pests viz., yellow stem borer (YSB) Scirpophaga incertulas, rice leaf folder (RLF) Cnaphalocrocis medinalis and one minor insect pest, oriental army worm (OAW) Mythimna separata was demonstrated through bioassays of transgenic rice plants under laboratory and greenhouse conditions. The rbcS1 promoter with chloroplast signal peptide was used to avoid Cry2AX1 protein expression in rice seed endosperm tissue. A total of 37 independent transformants were generated, of which after preliminary molecular characterization and YSB bioassay screening, five events were selected for their protein expression and bioefficacy against all three rice insect. One elite transgenic rice line, BtE15, was identified with Cry2AX1 expression ranging from 0.68 to 1.34 µg g(-1) leaf fresh weight and with 80-92 % levels of resistance against rice pests at the vegetative and reproductive stages. Increase in Cry2AX1 protein concentration was also observed with crop maturity. The Cry2AX1protein concentration in the de-husked seeds was negligible (as low as 2.7-3.6 ng g(-1)). These results indicate the potential application of cry2AX1 gene in rice for protection against YSB, RLF and OAW.
Alvarenga, Tavane A; de Oliveira, Pollyanna F; de Souza, Julia M; Tavares, Denise C; Andrade E Silva, Márcio L; Cunha, Wilson R; Groppo, Milton; Januário, Ana H; Magalhães, Lizandra G; Pauletti, Patrícia M
2016-11-23
Bioassay-guided study of the ethanol extract from the cashew Anacardium occidentale furnished cardol triene (1), cardol diene (2), anacardic acid triene (3), cardol monoene (4), anacardic acid diene (5), 2-methylcardol triene (6), and 2-methylcardol diene (7). 1D- and 2D-NMR experiments and HRMS analysis confirmed the structures of compounds 1-7. Compounds 2 and 7 were active against Schistosoma mansoni adult worms in vitro, with LC 50 values of 32.2 and 14.5 μM and selectivity indices of 6.1 and 21.2, respectively. Scanning electron microscopy of the tegument of male worms in the presence of compound 7 at 25 μM after 24 h of incubation showed severe damage as well as peeling and reduction in the number of spine tubercles. Transmission electron microscopy analyses revealed swollen mitochondrial membrane, vacuoles, and altered tegument in worms incubated with compound 2 (25 μM after 24 h). Worms incubated with compound 7 (25 μM after 24 h) had lysed interstitial tissue, degenerated mitochondria, and drastically altered tegument. Together, the results indicated that compound 7 presents promising in vitro schistosomicidal activity.
Hu, Liang; Ge, Anle; Wang, Xixian; Wang, Shanshan; Yue, Xinpei; Wang, Jie; Feng, Xiaojun; Du, Wei; Liu, Bi-Feng
2018-07-01
Immune response to environmental pathogen invasion is a complex process to prevent host from further damage. For quantitatively understanding immune responses and revealing the pathogenic environmental information, real-time monitoring of such a whole dynamic process with single-animal resolution in well-defined environments is highly desired. In this work, an integrated microfluidic device coupled with worm-based biosensor was proposed for in vivo studies of dynamic immune responses and antibiotics interference in infected C. elegans. Individual worms housed in chambers were exposed to the various pathogens and discontinuously manipulated for imaging with limited influence on physiological activities. The expression of immune responses gene (irg-1) was time-lapse measured in intact worms during pathogen infection. Results demonstrated that irg-1 gene could be induced in the presence of P. aeruginosa strain PA14 in a dose-dependent manner, and the survival of infected worm could be rescued under gentamicin or erythromycin treatments. We expect it to be a versatile platform to facilitate future studies on pathogenesis researches and rapid drug screen using C. elegans disease model. Copyright © 2018 Elsevier B.V. All rights reserved.
Stickel, William H.; Sheldon, William G.; Stickel, Lucille F.
1965-01-01
Numbers of American woodcocks (Philohela minor) were held in cages for experimental work lasting several months. Injuries caused by birds attempting to flush were greatly reduced by clipping feathers from one wing, by making cage walls opaque, and by using high cages or false ceilings of fabric. Size of cage was found not to be important, to judge from weight changes, so long as ample food was unmistakably available. Birds were kept in both large and small cages without social conflicts. Cages on the ground proved too unsanitary for long-term use; small steel cages with removable floors were practical but did not solve the sanitation problem. Living earthworms (Lumbricus terrestris) were provided daily in amounts roughly equal to weights of birds. Birds gained on this food when worms were offered in suitable ways. The feeding tray recommended is a large roasting pan with a snap-on metal rim that retards loss of worms. Trays contained moist peat in which birds probed for worms. Two efforts to keep woodcocks on a diet of red worms (Eisenia foetide) were unsuccessful; use of this worm was considered responsible. Woodcocks were handled and transported for short periods with least injury to them when they were rolled individually in soft bags.
Slotved, H C; Barnes, E H; Bjørn, H; Christensen, C M; Eriksen, L; Roepstorff, A; Nansen, P
1996-06-01
Four groups with three pigs in each group were inoculated with Oesophagostomum dentatum larvae (L3 larvae). Groups 1 and 3 were inoculated with 20,000 larvae, and Groups 2 and 4 with 200,000 larvae. On Days 11 and 34, respectively, Groups 1 and 2 and Groups 3 and 4 were slaughtered, and the contents from the large intestines collected. Subsamples of intestinal contents were mixed with agar to a final concentration of 1% agar and allowed to set. The worms were allowed to migrate from the agar-gel into 38 degrees C 0.9% saline overnight. Then the worms were collected on a sieve (38 microns mesh) and counted. The worms retained in the agar-gel were counted after pouring the melted agar through a sieve (38 microns mesh). The results showed that more than 95% of the worms migrated out of the agar-gel, and subsequently were available for counting in an almost clean suspension. Additionally the method yielded a high worm recovery; all stages were recovered. The recovery percentage was not significantly affected by either the dose of parasites or the time interval from slaughtering to start of incubation (37-128 min).
Higashibata, Akira; Hashizume, Toko; Nemoto, Kanako; Higashitani, Nahoko; Etheridge, Timothy; Mori, Chihiro; Harada, Shunsuke; Sugimoto, Tomoko; Szewczyk, Nathaniel J; Baba, Shoji A; Mogami, Yoshihiro; Fukui, Keiji; Higashitani, Atsushi
2016-01-01
Although muscle atrophy is a serious problem during spaceflight, little is known about the sequence of molecular events leading to atrophy in response to microgravity. We carried out a spaceflight experiment using Caenorhabditis elegans onboard the Japanese Experiment Module of the International Space Station. Worms were synchronously cultured in liquid media with bacterial food for 4 days under microgravity or on a 1-G centrifuge. Worms were visually observed for health and movement and then frozen. Upon return, we analyzed global gene and protein expression using DNA microarrays and mass spectrometry. Body length and fat accumulation were also analyzed. We found that in worms grown from the L1 larval stage to adulthood under microgravity, both gene and protein expression levels for muscular thick filaments, cytoskeletal elements, and mitochondrial metabolic enzymes decreased relative to parallel cultures on the 1-G centrifuge (95% confidence interval (P⩽0.05)). In addition, altered movement and decreased body length and fat accumulation were observed in the microgravity-cultured worms relative to the 1-G cultured worms. These results suggest protein expression changes that may account for the progressive muscular atrophy observed in astronauts. PMID:28725720
7 CFR 51.3146 - U.S. Extra No. 1.
Code of Federal Regulations, 2010 CFR
2010-01-01
... from decay, broken skins which are not healed, worms, worm holes and free from injury caused by split... spot, scale, scars, russeting, other disease, insects or mechanical or other means. (a) At least 75...
7 CFR 51.1280 - Serious damage.
Code of Federal Regulations, 2012 CFR
2012-01-01
.... (5) Insects: (i) Worm holes. More than three healed codling moth stings, of which not more than two... appearance to an equal extent. 2 (ii) Blister mite or canker worm injury which affects an aggregate area of...
Winter losses of Canada geese at Pea Island, North Carolina
Cowan, A.B.; Herman, C.M.
1955-01-01
Report of research and findings to date. Topics discussed include: studies on life history and biology of gizzard worm; results of autopsies; experiments on survival and transmission of gizzard worm eggs and larvae in both field and laboratory; persistence of infections; and results of infections in geese of different ages. Cause of deaths has not been finally determined, but indications are that gizzard worm is an important contributing factor and that poor physical condition, brought about at least partially by malnutrition, also contributes to the losses.
Normal and Reversed-Phase Thin Layer Chromatography of Green Leaf Extracts
ERIC Educational Resources Information Center
Sjursnes, Birte Johanne; Kvittingen, Lise; Schmid, Rudolf
2015-01-01
Introductory experiments of chromatography are often conducted by separating colored samples, such as inks, dyes, and plant extracts, using filter paper, chalk, or thin layer chromatography (TLC) plates with various solvent systems. Many simple experiments have been reported. The relationship between normal chromatography and reversed-phase…
Zhao, Yan-Tao; Ali, Arshad; Yan, En-Rong
2017-02-01
The plant economics spectrum that integrates the combination of leaf and wood syndromes provides a useful framework for the examination of species strategies at the whole-plant level. However, it remains unclear how species that differ in leaf habits and growth forms are integrated within the plant economics spectrum in subtropical forests. We measured five leaf and six wood traits across 58 subtropical plant species, which represented two leaf habits (evergreen vs deciduous) and two growth forms (tree vs shrub) in eastern China. Principal component analysis (PCA) was employed separately to construct the leaf (LES), wood (WES) and whole-plant (WPES) economics spectra. Leaf and wood traits are highly intra- and intercorrelated, thus defining not only the LES and WES, but also a WPES. Multi-trait variations in PCAs revealed that the traits which were representative of the acquisitive strategy, i.e., cheap tissue investment and rapid returns on that investment, were clustered at one end, while traits that represented the conservative strategy, i.e., expensive tissue investment and slower returns, were clustered at other end in each of the axes of the leaf and wood syndromes (PC1-axis) and the plant height strategy (PC2-axis). The local WPES, LES and WES were tightly correlated with each other. Evergreens shaped the conservative side, while deciduous species structured the acquisitive side of the WPES and LES. With respect to plant height strategies, trees formulated the acquisitive side and shrub species made up the conservative side of the WPES, LES and WES. In conclusion, our results suggested that the LES and WES were coordinated to a WPES for subtropical species. The finding of this local spectrum of plant form and function would be beneficial for modeling nutrient fluxes and species compositions in the changing climate, but also for understanding species strategies in an evolutionary context. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Ramesh, B. N.; Girish, T. K.; Raghavendra, R. H.; Naidu, K. Akhilender; Rao, U. J. S. Prasada; Rao, K. S.
2014-01-01
Background: Amyloidosis, oxidative stress and inflammation have been strongly implicated in neurodegenerative disorders like Alzheimer's disease. Traditionally, Caesalpinia crista and Centella asiatica leaf extracts are used to treat brain related diseases in India. C. crista is used as a mental relaxant drink as well as to treat inflammatory diseases, whereas C. asiatica is reported to be used to enhance memory and to treat dementia. Objective: The present study is aimed to understand the anti-oxidant and anti-inflammatory potential of C. asiatica and C. crista leaf extracts. Materials and Methods: Phenolic acid composition of the aqueous extracts of C. crista and C. asiatica were separated on a reverse phase C18 column (4.6 x 250 mm) using HPLC system. Antioxidant properties of the leaf extracts were determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and the reducing potential assay. The anti-inflammatory activities of aqueous extracts of C. crista and C. asiatica were studied using 5-lipoxygenase assay. Polymorphonuclear leukocytes (PMNLs) were isolated from blood by Ficoll-Histopaque density gradient followed by hypotonic lysis of erythrocytes. Results: Gallic, protocatechuic, gentisic, chlorogenic, caffeic, p-coumaric and ferulic acids were the phenolic acids identified in C. crista and C. asiatica leaf aqueous extracts. However, gallic acid and ferulic acid contents were much higher in C. crista compared to C. asiatica. Leaf extracts of C. asiatica and C. crista exhibited antioxidant properties and inhibited 5-lipoxygenase (anti-inflammatory) in a dose dependent manner. However, leaf extracts of C. crista had better antioxidant and anti-inflammatory activity compared to that of C. asiatica. The better activity of C. crista is attributed to high gallic acid and ferulic acid compared to C. asiatica. Conclusions: Thus, the leaf extract of C. crista can be a potential therapeutic role for Alzheimer's disease. PMID:24741275
Onoda, Yusuke; Schieving, Feike; Anten, Niels P. R.
2015-01-01
Plant leaves commonly exhibit a thin, flat structure that facilitates a high light interception per unit mass, but may increase risks of mechanical failure when subjected to gravity, wind and herbivory as well as other stresses. Leaf laminas are composed of thin epidermis layers and thicker intervening mesophyll layers, which resemble a composite material, i.e. sandwich structure, used in engineering constructions (e.g. airplane wings) where high bending stiffness with minimum weight is important. Yet, to what extent leaf laminas are mechanically designed and behave as a sandwich structure remains unclear. To resolve this issue, we developed and applied a novel method to estimate stiffness of epidermis- and mesophyll layers without separating the layers. Across a phylogenetically diverse range of 36 angiosperm species, the estimated Young’s moduli (a measure of stiffness) of mesophyll layers were much lower than those of the epidermis layers, indicating that leaf laminas behaved similarly to efficient sandwich structures. The stiffness of epidermis layers was higher in evergreen species than in deciduous species, and strongly associated with cuticle thickness. The ubiquitous nature of sandwich structures in leaves across studied species suggests that the sandwich structure has evolutionary advantages as it enables leaves to be simultaneously thin and flat, efficiently capturing light and maintaining mechanical stability under various stresses. PMID:25675956
Molecular and serological survey on taeniasis and cysticercosis in Kanchanaburi Province, Thailand.
Anantaphruti, Malinee T; Okamoto, Munehiro; Yoonuan, Tippayarat; Saguankiat, Surapol; Kusolsuk, Teera; Sato, Megumi; Sato, Marcello O; Sako, Yasuhito; Waikagul, Jitra; Ito, Akira
2010-09-01
A community-based field survey on taeniasis and cysticercosis was performed in two villages in Thong Pha Phum District, Kanchanaburi Province, central Thailand, where 3 Taenia species, T. solium, T. saginata and T. asiatica, are sympatrically occurring. Four (0.6%) out of 667 stool samples were egg-positive for Taenia sp. by Kato-Katz technique. Three out of those four persons and other three persons who were Taenia egg-negative but having a recent (<1 year) history of discharging worms in stool were treated with niclosamide. One Taenia egg-positive woman was not treated because of severe ascites. After treatment, three persons expelled long strobilae with scolices and two persons expelled strobilae without scolex. One Taenia egg-positive person did not expel any worms post-treatment. Among 5 persons, four expelled a single worm, whereas one expelled multiple worms, may be 6 worms but not confirmed by detection of scolices. One scolex was armed with hooklets, whereas 2 others did not. Multiplex PCR of 10 expelled proglottids (including 6 estimated worms from one patient) revealed that one sample was T. solium, one T. saginata, and 8 T. asiatica. A total of 159 residents agreed to receive a serological test for cysticercosis. By ELISA using partially purified glycoprotein antigen, 9 cases, 5 and 4 from villages A and B respectively, were found to be sero-positive. The five and an additional sample on the border line from village A were evaluated using confirmative immunoblot using recombinant chimeric antigen. Among the six samples, four including the border line sample were confirmed to be cysticercosis by immunoblotting. One of the 4 persons had neurological symptoms with nodular lesions in the brain by computed tomography. These 4 confirmed or suspected cysticercosis cases were free of T. solium worms, but two of them including confirmed NCC case had a past (>1 year) history of expelling proglottids in the stool.
NASA Astrophysics Data System (ADS)
Lenihan, H. S.; Mills, S. W.; Mullineaux, L. S.; Peterson, C. H.; Fisher, C. R.; Micheli, F.
2008-12-01
The structure and dynamics of marine communities are regulated in part by variation in recruitment. As in other ecosystems, recruitment at deep-sea hydrothermal vents is controlled by the interplay of propagule supply and behavior, gradients in physical-chemical conditions, and biotic interactions during pre- and post-settlement periods. Recent research along the East Pacific Rise indicates that inhibition of recently settled larvae by mobile predators (mainly limpets) influences patterns of recruitment and subsequent community succession. We conducted a manipulative experiment at the same sites (˜2510 m water depth) to test whether high-density assemblages of the mussel Bathymodiolus thermophilus also inhibit recruitment. In a preliminary study, recruitment of vent invertebrates within the faunal zone dominated by B. thermophilus was strikingly different at two sites, East Wall and Worm Hole. East Wall had high densities of mussels but very low total recruitment. In contrast, Worm Hole had few mussels but high recruitment. Using the submersible Alvin, we transplanted a large number of mussels from East Wall to Worm Hole and quantified recruitment on basalt blocks placed in three treatments: (1) naturally high densities of mussels at East Wall; (2) naturally low densities of mussels at Worm Hole; and (3) high densities of transplanted mussels at Worm Hole. After 11 months, a total of 24 taxa had recruited to the basalt blocks. Recruitment was 44-60% lower in the transplanted high-density mussel patch at Worm Hole and the natural high-density patch at East Wall than within the natural low-density patch at Worm Hole. Biotic processes that may have caused the pattern of recruitment observed included predation of larvae via water filtration by mussels, larval avoidance of superior competitors, interference competition, and enhanced predation by species within the mussel-bed community. Our results indicate that biotic interactions affecting recruitment must be understood to explain patterns of invertebrate community organization and dynamics at hydrothermal vents.
Rehman, Abdur; Ullah, Rizwan; Jaiswal, Neeshma; Khan, M A Hannan; Rehman, Lubna; Beg, Mirza Ahmar; Malhotra, Sandeep K; Abidi, S M A
2017-12-01
The helminth parasites possess great capabilities to adapt themselves within their hosts and also develop strategies to render the commonly used anthelmintics ineffective leading to the development of resistance against these drugs. Besides using anthelmintics the natural products have also been tested for their anti-parasitic effects. Therapeutic efficacy of honey bee venom (HBV) has been tested in various ailments including some protozoal infections but very little is known about its anthelmintic properties. To investigate the anthelmintic effect of HBV the excysted progenetic metacercariae of Clinostomum complanatum, a heamophagic, digenetic trematode with zoonotic potential, infecting a wide variety of hosts, were obtained from Trichogaster fasciatus, a forage fish, which serves as the intermediate host. The metacercarial worms were in vitro incubated in RPMI-1640 medium containing HBV along with the controls which were devoid of HBV for the analysis of worm motility, enzyme activity, polypeptide profile and surface topographical changes. The motility of the worms was significantly reduced in a time dependent manner with an increase in the concentration of HBV. Following incubation of worms the release of cysteine proteases was inhibited in the presence of HBV as revealed by gelatine substrate gel zymography. As well as the polypeptide profile was also significantly influenced, particularly intensity/expression of M r 19.4 kDa, 24 kDa and 34 kDa was significantly reduced upon HBV treatment. The HBV treatment also inhibited antioxidant enzyme, superoxide dismutase (SOD) and Glutathione-S-transferase (GST) significantly (p < 0.05) in the worms. The scanning electron microscopy of the HBV treated worms revealed tegumental disruptions and erosion of papillae as well as spines showing vacuolation in the tegument. The HBV treated worms also showed a marked decline in the transformation rate when introduced into an experimental host which further reflect the anthelmintic potential of HBV. Copyright © 2017 Elsevier Inc. All rights reserved.
Hansen, Tina V A; Nejsum, Peter; Friis, Christian; Olsen, Annette; Thamsborg, Stig Milan
2014-04-01
The single-dose benzimidazoles used against Trichuris trichiura infections in humans are not satisfactory. Likewise, the benzimidazole, fenbendazole, has varied efficacy against Trichuris suis whereas Oesophagostomum dentatum is highly sensitive to the drug. The reasons for low treatment efficacy of Trichuris spp. infections are not known. We studied the effect of fenbendazole, albendazole and levamisole on the motility of T. suis and O. dentatum and measured concentrations of the parent drug compounds and metabolites of the benzimidazoles within worms in vitro. The motility and concentrations of drug compounds within worms were compared between species and the maximum specific binding capacity (Bmax) of T. suis and O. dentatum towards the benzimidazoles was estimated. Comparisons of drug uptake in living and killed worms were made for both species. The motility of T. suis was generally less decreased than the motility of O. dentatum when incubated in benzimidazoles, but was more decreased when incubated in levamisole. The Bmax were significantly lower for T. suis (106.6, and 612.7 pmol/mg dry worm tissue) than O. dentatum (395.2, 958.1 pmol/mg dry worm tissue) when incubated for 72 hours in fenbendazole and albendazole respectively. The total drug concentrations (pmol/mg dry worm tissue) were significantly lower within T. suis than O. dentatum whether killed or alive when incubated in all tested drugs (except in living worms exposed to fenbendazole). Relatively high proportions of the anthelmintic inactive metabolite fenbendazole sulphone was measured within T. suis (6-17.2%) as compared to O. dentatum (0.8-0.9%). The general lower sensitivity of T. suis towards BZs in vitro seems to be related to a lower drug uptake. Furthermore, the relatively high occurrence of fenbendazole sulphone suggests a higher detoxifying capacity of T. suis as compared to O. dentatum.
Hansen, Tina V. A.; Nejsum, Peter; Friis, Christian; Olsen, Annette; Thamsborg, Stig Milan
2014-01-01
Background The single-dose benzimidazoles used against Trichuris trichiura infections in humans are not satisfactory. Likewise, the benzimidazole, fenbendazole, has varied efficacy against Trichuris suis whereas Oesophagostomum dentatum is highly sensitive to the drug. The reasons for low treatment efficacy of Trichuris spp. infections are not known. Methodology We studied the effect of fenbendazole, albendazole and levamisole on the motility of T. suis and O. dentatum and measured concentrations of the parent drug compounds and metabolites of the benzimidazoles within worms in vitro. The motility and concentrations of drug compounds within worms were compared between species and the maximum specific binding capacity (Bmax) of T. suis and O. dentatum towards the benzimidazoles was estimated. Comparisons of drug uptake in living and killed worms were made for both species. Principal findings The motility of T. suis was generally less decreased than the motility of O. dentatum when incubated in benzimidazoles, but was more decreased when incubated in levamisole. The Bmax were significantly lower for T. suis (106.6, and 612.7 pmol/mg dry worm tissue) than O. dentatum (395.2, 958.1 pmol/mg dry worm tissue) when incubated for 72 hours in fenbendazole and albendazole respectively. The total drug concentrations (pmol/mg dry worm tissue) were significantly lower within T. suis than O. dentatum whether killed or alive when incubated in all tested drugs (except in living worms exposed to fenbendazole). Relatively high proportions of the anthelmintic inactive metabolite fenbendazole sulphone was measured within T. suis (6–17.2%) as compared to O. dentatum (0.8–0.9%). Conclusion/Significance The general lower sensitivity of T. suis towards BZs in vitro seems to be related to a lower drug uptake. Furthermore, the relatively high occurrence of fenbendazole sulphone suggests a higher detoxifying capacity of T. suis as compared to O. dentatum. PMID:24699263
Defeating "the worm" in Rajasthan. Women and water: India.
Datta, B
1993-01-01
In theory, the Indian government's SWACH project uses an integrated approach to sanitation, water, and community health, but its priority is guinea worm control. It operates in 4 districts of Rajasthan. Ways to break the guinea worm cycle are converting step wells to draw wells, provision of hand pumps, teaching people to filter water before drinking it, and ayurvedic techniques to remove the guinea worm from the body before it breaks through the skin, at which point it becomes ineffective. Between 1986 and 1992, SWACH's efforts reduced the guinea worm cases 10-fold (from about 8000 to 800). In 1990 Sarsiya had 56 cases, but in 1992 it had none. SWACH has trained 70 local women to do handpump maintenance. It is in their interest to be handpump mechanics, since women collect the water. The village governments contract handpump repair out to these women. Each mechanic is responsible for handpump maintenance in about 10 villages. Even though the women complain that villagers do not know how to use handpumps, they do not teach then how to use the pumps. In fact, this reflects the project's lack of a broader approach to health education. SWACH's strength lies in the tangibles (e.g., handpumps and water filters). It has brought potable water to almost 1.5 million Indians. Most villagers are guinea worm specialists, but know little about other waterborne diseases and infectious diseases. SWACH does not monitor its effects on the prevalence of other waterborne diseases. SWACH staff also neglect community health. For example, a local midwife in the remote tribal village of Sarsiya was surprised to learn that she can prevent infection by boiling blades. She explained that SWACH field workers never informed her about the benefits of boiling. A man who once had guinea worm disease did not know how one gets it, yet SWACH staff treated him. Evaluations note the gap between project staff and villagers.
Vallance, Bruce A.; Galeazzi, Francesca; Collins, Stephen M.; Snider, Denis P.
1999-01-01
Expulsion of intestinal nematode parasites and the associated increased contraction by intestinal muscle are T cell dependent, since both are attenuated in athymic rodents. The CD4 T-cell subset has been strongly associated with worm expulsion; however, the relationship between these cells, antigen presentation, and worm expulsion is not definitive and the role of these factors in intestinal muscle hypercontractility has not been defined. We infected C57BL/6, athymic, CD4-deficient, CD8α-deficient, and major histocompatibility complex class II (MHC II)-deficient (C2d) mice with Trichinella spiralis larvae. We examined intestinal worm numbers, longitudinal muscle contraction, and MHC II expression. Numerous MHC II-positive cells were identified within the muscularis externa of infected but not uninfected C57BL/6 mice. C57BL/6 and CD8α-deficient mice developed large increases in muscle contraction, expelling the parasite by day 21. Athymic and C2d mice exhibited much smaller increases in muscle contraction and delayed parasite expulsion. CD4-deficient mice exhibited intermediate levels of muscle contraction and delayed parasite expulsion. To further examine the role of MHC II and CD4 T cells, we irradiated C2d mice and reconstituted them with C57BL/6 bone marrow alone or with C57BL/6 CD4 T cells. C57BL/6 bone marrow alone did not affect muscle function or worm expulsion in recipient C2d mice. Partial CD4 T-cell reconstitution was sufficient to restore increased muscle contraction but not worm expulsion. Thus, hematopoietic MHC II expression alone is insufficient for the development of muscle hypercontractility and worm expulsion, but the addition of even small numbers of CD4 T cells was sufficient to induce intestinal muscle pathophysiology. PMID:10531271
Jarvi, Susan I; Quarta, Stefano; Jacquier, Steven; Howe, Kathleen; Bicakci, Deniz; Dasalla, Crystal; Lovesy, Noelle; Snook, Kirsten; McHugh, Robert; Niebuhr, Chris N
2017-01-01
The nematode Angiostrongylus cantonensis is a zoonotic pathogen and the etiological agent of human angiostrongyliasis or rat lungworm disease. Hawai'i, particularly east Hawai'i Island, is the epicenter for angiostrongyliasis in the USA. Rats (Rattus spp.) are the definitive hosts while gastropods are intermediate hosts. The main objective of this study was to collect adult A. cantonensis from wild rats to isolate protein for the development of a blood-based diagnostic, in the process we evaluated the prevalence of infection in wild rats. A total of 545 wild rats were sampled from multiple sites in the South Hilo District of east Hawai'i Island. Adult male and female A. cantonensis (3,148) were collected from the hearts and lungs of humanely euthanized Rattus rattus, and R. exulans. Photomicrography and documentation of multiple stages of this parasitic nematode in situ were recorded. A total of 45.5% (197/433) of rats inspected had lung lobe(s) (mostly upper right) which appeared granular indicating this lobe may serve as a filter for worm passage to the rest of the lung. Across Rattus spp., 72.7% (396/545) were infected with adult worms, but 93.9% (512/545) of the rats were positive for A. cantonensis infection based on presence of live adult worms, encysted adult worms, L3 larvae and/or by PCR analysis of brain tissue. In R. rattus we observed an inverse correlation with increased body mass and infection level of adult worms, and a direct correlation between body mass and encysted adult worms in the lung tissue, indicating that larger (older) rats may have developed a means of clearing infections or regulating the worm burden upon reinfection. The exceptionally high prevalence of A. cantonensis infection in Rattus spp. in east Hawai'i Island is cause for concern and indicates the potential for human infection with this emerging zoonosis is greater than previously thought.
Effects of alcoholic extract of Curcuma longa on Ascaridia infestation affecting chicken.
Alrubaie, Abdulrazak Labi
2015-07-01
Ascaridia galli, the common intestinal nematode, remains a major cause of economic loss in the poultry industry in developing countries. Treatments using chemicals are not only expensive but also affect host health. Plant extracts as better alternative is gaining significance. Here, we have studied the effects of alcoholic extract of turmeric, Curcuma longa L. (Zingiberaceae) roots, against A. galli infection in chicken. Different concentrations of C. longa root extract were tested in vitro on 5 groups of adults A. galli worms and in vivo on 6 groups of chicks. The results showed that the turmeric root extract @ 60 mg mL(-1) in vitro significantly (P < 0.001) proved paralytic and fatal against worms (16.80 ± 1.28 h). In vivo, chicken groups (G2-G6) were infected with an average of 300 ± 12 embryonated eggs of A. galli. The G2 was not given any treatment while G3 was treated with piperazine (@ 200 mg kg(-1) body wt.); and Groups 4, 5 and 6 were given turmeric @ 200, 400 and 600 mg kg(-1) body wt., respectively. The mean number of worms extracted at the end of the trial in G2 (untreated) was 18.10 ± 2.42, while the G3 treated with piperazine had no worms. Groups 4 and 5 did not show any significant difference compared to G2. However, G6 that had 3.20 ± 1.33 worms was statistically significant. Higher concentrations of turmeric given to infected chickens significantly reduced the length and weight of worms. The study showed that the worm infestation damaged the intestinal villi, and.treatment with high concentration of C. longa had healing effects and restored the integrity of intestinal mucosa. The results have demonstrated the ameliorating effect of C. longa turmeric on A. galli infested chickens.
NASA Technical Reports Server (NTRS)
Bugbee, B.; White, J. W.; Salisbury, F. B. (Principal Investigator)
1984-01-01
The effect of root-zone temperature on young tomato plants (Lycopersicon esculentum Mill. cv. Heinz 1350) was evaluated in controlled environments using a recirculating solution culture system. Growth rates were measured at root-zone temperatures of 15 degrees, 20 degrees, 25 degrees, and 30 degrees C in a near optimum foliar environment. Optimum growth occurred at 25 degrees to 30 degrees during the first 4 weeks of growth and 20 degrees to 25 degrees during the 5th and 6th weeks. Growth was severely restricted at 15 degrees. Four concentrations of gibberellic acid (GA3) and kinetin were added to the nutrient solution in a separate trial; root-zone temperature was maintained at 15 degrees and 25 degrees. Addition of 15 micromoles GA3 to solutions increased specific leaf area, total leaf area, and dry weight production of plants in both temperature treatments. GA3-induced growth stimulation was greater at 15 degrees than at 25 degrees. GA3 may promote growth by increasing leaf area, enhancing photosynthesis per unit leaf area, or both. Kinetic was not useful in promoting growth at either temperature.
Code of Federal Regulations, 2014 CFR
2014-01-01
... formed, clean, and free from decay, broken skins which are not healed, worms, worm holes, and free from... not less than one-third of its surface showing red color characteristic of the variety. (See § 51.3150...
Code of Federal Regulations, 2013 CFR
2013-01-01
... formed, clean, and free from decay, broken skins which are not healed, worms, worm holes, and free from... not less than one-third of its surface showing red color characteristic of the variety. (See § 51.3150...
Hybrid epidemics--a case study on computer worm conficker.
Zhang, Changwang; Zhou, Shi; Chain, Benjamin M
2015-01-01
Conficker is a computer worm that erupted on the Internet in 2008. It is unique in combining three different spreading strategies: local probing, neighbourhood probing, and global probing. We propose a mathematical model that combines three modes of spreading: local, neighbourhood, and global, to capture the worm's spreading behaviour. The parameters of the model are inferred directly from network data obtained during the first day of the Conficker epidemic. The model is then used to explore the tradeoff between spreading modes in determining the worm's effectiveness. Our results show that the Conficker epidemic is an example of a critically hybrid epidemic, in which the different modes of spreading in isolation do not lead to successful epidemics. Such hybrid spreading strategies may be used beneficially to provide the most effective strategies for promulgating information across a large population. When used maliciously, however, they can present a dangerous challenge to current internet security protocols.
Symbiosis insights through metagenomic analysis of a microbial consortium.
Woyke, Tanja; Teeling, Hanno; Ivanova, Natalia N; Huntemann, Marcel; Richter, Michael; Gloeckner, Frank Oliver; Boffelli, Dario; Anderson, Iain J; Barry, Kerrie W; Shapiro, Harris J; Szeto, Ernest; Kyrpides, Nikos C; Mussmann, Marc; Amann, Rudolf; Bergin, Claudia; Ruehland, Caroline; Rubin, Edward M; Dubilier, Nicole
2006-10-26
Symbioses between bacteria and eukaryotes are ubiquitous, yet our understanding of the interactions driving these associations is hampered by our inability to cultivate most host-associated microbes. Here we use a metagenomic approach to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia. Shotgun sequencing and metabolic pathway reconstruction revealed that the symbionts are sulphur-oxidizing and sulphate-reducing bacteria, all of which are capable of carbon fixation, thus providing the host with multiple sources of nutrition. Molecular evidence for the uptake and recycling of worm waste products by the symbionts suggests how the worm could eliminate its excretory system, an adaptation unique among annelid worms. We propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits.
Logistics of Guinea Worm Disease Eradication in South Sudan
Jones, Alexander H.; Becknell, Steven; Withers, P. Craig; Ruiz-Tiben, Ernesto; Hopkins, Donald R.; Stobbelaar, David; Makoy, Samuel Yibi
2014-01-01
From 2006 to 2012, the South Sudan Guinea Worm Eradication Program reduced new Guinea worm disease (dracunculiasis) cases by over 90%, despite substantial programmatic challenges. Program logistics have played a key role in program achievements to date. The program uses disease surveillance and program performance data and integrated technical–logistical staffing to maintain flexible and effective logistical support for active community-based surveillance and intervention delivery in thousands of remote communities. Lessons learned from logistical design and management can resonate across similar complex surveillance and public health intervention delivery programs, such as mass drug administration for the control of neglected tropical diseases and other disease eradication programs. Logistical challenges in various public health scenarios and the pivotal contribution of logistics to Guinea worm case reductions in South Sudan underscore the need for additional inquiry into the role of logistics in public health programming in low-income countries. PMID:24445199
Logistics of Guinea worm disease eradication in South Sudan.
Jones, Alexander H; Becknell, Steven; Withers, P Craig; Ruiz-Tiben, Ernesto; Hopkins, Donald R; Stobbelaar, David; Makoy, Samuel Yibi
2014-03-01
From 2006 to 2012, the South Sudan Guinea Worm Eradication Program reduced new Guinea worm disease (dracunculiasis) cases by over 90%, despite substantial programmatic challenges. Program logistics have played a key role in program achievements to date. The program uses disease surveillance and program performance data and integrated technical-logistical staffing to maintain flexible and effective logistical support for active community-based surveillance and intervention delivery in thousands of remote communities. Lessons learned from logistical design and management can resonate across similar complex surveillance and public health intervention delivery programs, such as mass drug administration for the control of neglected tropical diseases and other disease eradication programs. Logistical challenges in various public health scenarios and the pivotal contribution of logistics to Guinea worm case reductions in South Sudan underscore the need for additional inquiry into the role of logistics in public health programming in low-income countries.
Rehbein, S; Lindner, T; Kollmannsberger, M; Winter, R; Visser, M
1997-06-01
The distribution of Chabertia (Ch.) ovina, Oesophagostomum (O.) venulosum and Trichuris spp. within the large intestine of naturally infected sheep in the dependence of worm counts and the presence of nematodes of other species or genera was evaluated. The large intestine was divided into 4 sections. More than 75% of Ch. ovina were found within the disk-like section of the colon independently from worm count and presence of nematodes of other species. O. venulosum and Trichuris spp. preferred the caecum and the first section of the colon up to the beginning of the disk-like section. In both, the share of worms recovered from the first section of the colon did increase with higher worm counts. The simultaneous presence of O. venulosum and Trichuris spp. had a significantly negative influence on the share of Trichuris spp. isolated from the caecum.
Mitchell, Daniel E; Lovett, Joseph R; Armes, Steven P; Gibson, Matthew I
2016-02-18
The first fully synthetic polymer-based approach for red-blood-cell cryopreservation without the need for any (toxic) organic solvents is reported. Highly hydroxylated block copolymer worms are shown to be a suitable replacement for hydroxyethyl starch as a extracellular matrix for red blood cells. When used alone, the worms are not a particularly effective preservative. However, when combined with poly(vinyl alcohol), a known ice-recrystallization inhibitor, a remarkable additive cryopreservative effect is observed that matches the performance of hydroxyethyl starch. Moreover, these block copolymer worms enable post-thaw gelation by simply warming to 20 °C. This approach offers a new solution for both the storage and transport of red blood cells and also a convenient matrix for subsequent 3D cell cultures. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Modern Antarctic acorn worms form tubes.
Halanych, Kenneth M; Cannon, Johanna T; Mahon, Andrew R; Swalla, Billie J; Smith, Craig R
2013-01-01
Acorn worms, or enteropneusts, are vermiform hemichordates that occupy an important position in deuterostome phylogeny. Allied to pterobranch hemichordates, small colonial tube dwellers, modern enteropneusts were thought to be tubeless. However, understanding of hemichordate diversity is poor, as evidenced by absence of reports from some oceanic regions and recent descriptions of large epibenthic deep-water enteropneusts, Torquaratoridae. Here we show, based on expeditions to Antarctica, that some acorn worms produce conspicuous tubes that persist for days. Interestingly, recent fossil descriptions show a Middle Cambrian acorn worm lived in tubes, leading to speculation that these fossils may have been pterobranch forbearers. Our discovery provides the alternative interpretation that these fossils are similar to modern-day torquaratorids and that some behaviours have been conserved for over 500 million years. Moreover, the frequency of Antarctic enteropneusts observed attests to our limited knowledge of Antarctic marine ecosystems, and strengthens hypotheses relating more northern deep-sea fauna to Antarctic shelf fauna.
NASA Astrophysics Data System (ADS)
Hammond, Timothy G.; Birdsall, Holly H.; Hammond, Jeffrey S.; Allen, Patricia L.
2013-02-01
This study addresses controls for an assay of bacterial virulence that has been optimized for space flight studies. Caenorhabditis elegans (C. elegans) worms ingest microorganisms, but are also killed by virulent bacteria. Virulence is assessed by the number of bacteria surviving in co-culture with C. elegans , as measured by optical density at 620 nm. Co -cultures of Methicillin-resistant Staphylococcus aureus (MRSA) with C. elegans have a higher OD620 than MRSA grown alone, which could reflect debris from dead worms and/or enhanced growth of the MRSA in response to worm-derived factors. The use of media conditioned by pre-incubation with worms demonstrated the presence of temperature-stable factors that change MRSA growth in a strain-dependent manner. Some sources of deionized water contain an undefined antibacterial activity present in conditioned, but not fresh untreated media.
Gong, Ping; Escalon, B Lynn; Hayes, Charolett A; Perkins, Edward J
2008-02-01
The explosive compound hexanitrohexaazaisowurtzitane (CL-20) has been shown to cause both lethal and sublethal (reproductive and neurotoxic) effects in exposed oligochaetes. However, whether worms take up CL-20 and how much CL-20 enters worm bodies leading to toxicity (e.g., lethality) remain to be determined. In the present study, we used high performance liquid chromatography (HPLC) and radiolabeled tracer methods to investigate the CL-20 uptake in the whole worm body after contact exposures. Worms (Eisenia fetida) were exposed to filter paper spiked with non-radioactive or [U-(14)C]-labeled CL-20 for 1-3 d. The radiolabeled tracer method allowed us to detect the parent compound and transformation products in worms exposed to as low as 0.04 microg CL-20 cm(-2) of filter paper. The HPLC method without radiolabeled tracer was far less sensitive with a detection limit of 2.17 microg CL-20 cm(-2). Using the radiolabeled tracer, we were able to demonstrate that the worm body concentration linearly correlated to the filter paper concentration < or =0.34 microg cm(-2) (r=0.94) if no breakdown products are assumed. At higher concentrations, the body concentration increased slowly and saturated at around 11 microg g(-1) dry mass resulting in an estimated lethal critical body burden of 10-15 microg CL-20 g(-1) dry mass. These findings demonstrate that CL-20 or potential transformation products are taken into the earthworm body through dermal contact. This information should prove valuable in assessing the bioaccumulation potential and ecological risks of CL-20.
Al-Jahdali, M O
2012-08-01
In hermaphroditic helminth parasites, infrapopulation size or mating group size mostly affects some processes acting within the infrapopulation. Here, 30 natural infrapopulations (12-154 individuals) of the intestinal trematode Gyliauchen volubilis Nagaty, 1956 from the fish Siganus rivulatus consisting of newly excysted juveniles, immature and mature worms were found distributed in a well-defined fundamental niche (anterior 40% of the intestine). In small infrapopulations, all stages of the parasite were alive. In larger infrapopulations, differential mortality was only and consistently observed among newly excysted juveniles, and gradually increased to include most or all juveniles in the largest infrapopulations. Among mature worms, the mean worm length seemed unaffected by the infrapopulation size. However, the ratio mean testis size-mean ovary size, a reliable indicator of resource allocation to the male function and of opportunities for cross fertilization, significantly increased with mating group size. In small infrapopulations, all stages of the parasite were scattered along the niche, and never seen in mating pairs (possibly reproduced by self-fertilization). In larger infrapopulations, newly excysted juveniles and immature worms were scattered along the anterior two thirds of the niche, while mature worms were constantly found aggregated in its posterior third (narrow microhabitat), where some were arranged in mating pairs. The probability of mating reciprocally or unilaterally was dependent on body size. The mean number of uterine eggs per worm significantly decreased and their mean sizes significantly increased with mating group size. The results are statistically significant and suggest that infrapopulation self-regulation is greatly associated with its size.
Ogino, Tetsuya; Maegawa, Shingo; Shigeno, Shuichi; Fujikura, Katsunori; Toyohara, Haruhiko
2018-01-01
The environments around deep-sea hydrothermal vents are very harsh conditions for organisms due to the possibility of exposure to highly toxic compounds and extremely hot venting there. Despite such extreme environments, some indigenous species have thrived there. Alvinellid worms (Annelida) are among the organisms best adapted to high-temperature and oxidatively stressful venting regions. Although intensive studies of the adaptation of these worms to the environments of hydrothermal vents have been made, little is known about the worms' sensory adaptation to the severe chemical conditions there. To examine the sensitivity of the vent-endemic worm Paralvinella hessleri to low pH and oxidative stress, we determined the concentration of acetic acid and hydrogen peroxide that induced avoidance behavior of this worm, and compared these concentrations to those obtained for related species inhabiting intertidal zones, Thelepus sp. The concentrations of the chemicals that induced avoidance behavior of P. hessleri were 10-100 times lower than those for Thelepus sp. To identify the receptors for these chemicals, chemical avoidance tests were performed with the addition of ruthenium red, a blocker of transient receptor potential (TRP) channels. This treatment suppressed the chemical avoidance behavior of P. hessleri, which suggests that TRP channels are involved in the chemical avoidance behavior of this species. Our results revealed for the first time hypersensitive detection systems for acid and for oxidative stress in the vent-endemic worm P. hessleri, possibly mediated by TRP channels, suggesting that such sensory systems may have facilitated the adaptation of this organism to harsh vent environments.
Dunham, N R; Peper, S T; Downing, C; Brake, E; Rollins, D; Kendall, R J
2017-09-01
Northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) have experienced chronic declines within the Rolling Plains ecoregion of Texas. Parasitic infection, which has long been dismissed as a problem in quail, has not been studied thoroughly until recently. A total of 219 northern bobwhite and 101 scaled quail from Mitchell County, Texas were captured and donated from 2014 to 2015, and examined for eyeworm (Oxyspirura petrowi) and caecal worm (Aulonocephalus pennula) infections. In 2014, bobwhites averaged 19.6 ± 1.8 eyeworms and 98.6 ± 8.2 caecal worms, and 23.5 ± 2.1 eyeworms and 129.9 ± 10.7 caecal worms in 2015. Scaled quail averaged 4.8 ± 1.0 eyeworms and 50 ± 6.8 caecal worms in 2014, and 5.7 ± 1.3 eyeworms and 38.1 ± 7.1 caecal worms in 2015. This study expands the knowledge of parasitic infection in quail inhabiting the Rolling Plains of Texas. A significant difference was documented in O. petrowi infection between species but there was no significant difference in A. pennula between quail species. No significant difference was detected in parasite infection between the sexes of both northern bobwhite and scaled quail. This study also documented the highest reported O. petrowi infection in both species of quail. Additional research is needed on the life history and infection dynamics of O. petrowi and A. pennula infections to determine if there are individual- and/or population-level implications due to parasitic infection.
Cheung, Lumei; Beshah, Ethiopia; Shea-Donohue, Terez; Urban, Joseph F.
2013-01-01
Heligmosomoides bakeri is a nematode with parasitic development exclusively in the small intestine of infected mice that induces a potent STAT6-dependent Th2 immune response. We previously demonstrated that host protective expulsion of adult H. bakeri worms from a challenge infection was delayed in selenium (Se)-deficient mice. In order to explore mechanisms associated with the delayed expulsion, 3-week-old female BALB/c mice were placed on a torula yeast-based diet with or without 0.2 ppm Se, and after 5 weeks, they were inoculated with H. bakeri infective third-stage larvae (L3s). Two weeks after inoculation, the mice were treated with an anthelmintic and then rested, reinoculated with L3s, and evaluated at various times after reinoculation. Analysis of gene expression in parasite-induced cysts and surrounding tissue isolated from the intestine of infected mice showed that the local-tissue Th2 response was decreased in Se-deficient mice compared to that in Se-adequate mice. In addition, adult worms recovered from Se-deficient mice had higher ATP levels than worms from Se-adequate mice, indicating greater metabolic activity in the face of a suboptimal Se-dependent local immune response. Notably, the process of worm expulsion was restored within 2 to 4 days after feeding a Se-adequate diet to Se-deficient mice. Expulsion was associated with an increased local expression of Th2-associated genes in the small intestine, intestinal glutathione peroxidase activity, secreted Relm-β protein, anti-H. bakeri IgG1 production, and reduced worm fecundity and ATP-dependent metabolic activity. PMID:23649095
Still and Moving Image Evidences for Mating of Echinococcus granulosus Reared in Culture Media.
Mohammadzadeh, Tahereh; Sadjjadi, Seyed Mahmoud; Rahimi, Hamidreza
2014-03-01
Echinococcus granulosus cultivation is very important for improvement of different aspect of medical and veterinary researches. Despite many advances in this case, there is a missing link for in vitro life cycle of adult worms and it is fertilization. Regarding the researchers' observations, self-fertilization can be done in worms living in dog intestine, but despite all sorts of experimental techniques, this phenomenon has never been observed in reared worms in culture media. Furthermore, cross fertilization has not been observed in vitro and even in parasites with dog intestinal origin; although it theoretically is possible. During a follow-up of cultivated adult worms, evidences of behaviors similar to self-mating (Type 2) and cross-mating were observed in our lab which will be presented here. Protoscoleces were aseptically removed from sheep hydatid cysts, washed twice with PBS and then cultivated in S.10E.H culture medium. The stages of parasite growth were observed using an inverted microscope for two months and all stages and behaviors were microscopically photographed. Different movies have also been made from these behavioral features. After around 55 days post cultivation, some evidences of behaviors similar to self-mating (Type 2) and cross-mating were observed in some of the mature adult worms. However, fertile eggs in these parasites have never been observed. Regarding the above observations, these parasites show tendency to unsuccessful self-mating/fertilization (type 2) which failure could be due to anatomical position and physiological maturation. Also lack of suitable conditions for self-fertilization causes the worms try to do unsuccessful cross- mating/fertilization in culture media.
A reversible bipolar WORM device based on AlOxNy thin film with Al nano phase embedded
NASA Astrophysics Data System (ADS)
Zhu, W.; Li, J.; Zhang, L.; Hu, X. C.
2017-03-01
An Al-rich AlOxNy thin film based reversible Write-Once-Read-Many-Times (WORM) memory device with MIS structure could transit from high resistance state (HRS, ∼1011 Ω) to low resistance state (LRS, ∼105 Ω) by sweeping voltage up to ∼20 V. The first switching could be recorded as writing process for WORM device which may relate to conductive path are formed through the thin film. The conductive path should be formed by both Al nano phase and oxygen vacancies. Among of them, Al nano phases are not easy to move, but oxygen vacancies could migrate under high E-field or at high temperature environment. Such conductive path is not sensitive to charging effect after it formed, but it could be broken by heating effect, which may relate to the migration of excess Al ions and oxygen vacancies at high temperature. After baking LRS (ON state) WORM device at 200 °C for 2 min, the conductivity will decrease to HRS which indicates conductive path is broken and device back to HRS (OFF state) again. This phenomenon could be recorded as recovery process. Both writing and recovery process related to migration of oxygen vacancies and could be repeated over 10 times in this study. It also indicates that there is no permanent breakdown occurred in MIS structured WORM device operation. We suggest that this conductive path only can be dissolved by a temperature sensitive electro-chemical action. This WORM device could maintain at LRS over 105 s with on-off ratio over 4 orders.
Singh, Ravendra Kumar; Chavan, Sugandha L; Sapkale, Pravin H
2007-06-01
Live feeds, especially Tubifex spp., which are collected from a wide variety of polluted habitats, are used by aquarium fish keepers in India. These habitats receive domestic sewage and industrial wastes from nearby residential and industrial areas. Reports of morbidity and mortality from aquarium fish culturists in and around Mumbai led to the present investigations on the ecology of these habitats with a view to assess the water quality, presence of heavy metals in the environment and their bioaccumulation in Tubifex worms, and to examine whether these habitats could be exploited to meet the demand of the industry. Six natural red worm (Tubifex spp.) collection centres in Mumbai and Thane districts of Maharashtra state in India constituting a major source of live Tubifex supply to aquarium fish industry were evaluated for pollution, heavy metal concentration in water, sediments and in the body tissues of Tubifex. Data revealed the presence of heavy metals in water and sediments at collection sites and bioaccumulation of cadmium, iron, lead, zinc and copper in body tissues of Tubifex worms. Cadmium ranged from 2.38 to 7.21 mg/kg, iron 671.9 to 5738 mg/kg, lead 14.95 to 33.49 mg/kg, zinc 60.20 to 166.60 mg/kg and copper 29.38 to 108.90 mg/kg of dry Tubifex worms. The study suggests that all the six collection sites are polluted and the red worms contaminated with heavy metals and hence, unfit for use in aquaria or feeding any variety of fish or crustaceans in the hatcheries.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephenson, G.L.; Scroggins, R.
Environment Canada has embarked on a five year program to develop, standardize, and validate a battery of soil toxicity tests which can be used to assess the relative toxicity of contaminants in soils to terrestrial organisms. These tests must be applicable to soil conditions typically found in Canadian environments and the test species must be representative of the species of soil invertebrates or plants inhabiting soil ecosystems in Canada. One of the toxicity tests being developed is designed to assess the toxicity of contaminated soils to earthworms. Five of the potential test species belong to the Lumbricidae family and includemore » the Canadian worm (Allobophora calignosa/Aporrectodea tuberculate), the European bark worm (Dendrodtilus rubidus (rubida)), the pink soil worm (Eisenia rosea), the red marsh worm (Lumbricus rubellus), and the Canadian night crawler or dew worm (Lumbricus terrestris). The sixth species, the white pot worm (Enchytraeus albidus), belongs to the Enchytraeidae family. Further assessment reduced the number of representative species to three. Most earthworm test methods have been developed to assess the toxicity of chemically-spiked artificial soils to Eisenia fetida or E. andrei. Test methods have also been developed to assess the relative toxicity of contaminated soils from hazardous waste sites. Comparative acute toxicity data for three species of earthworm exposed to a hydrocarbon contamination will be presented. Comparative toxicity data for the same three species of earthworm will also be presented using test procedures and conditions that have been modified to accommodate biological differences among the species of earthworm. Recommendations regarding test design, methods, and conditions optimal for each test species will be summarized and discussed with respect to the precision of test results.« less
Rojas, Alicia; Sanchis-Monsonís, Gloria; Alić, Amer; Hodžić, Adnan; Otranto, Domenico; Yasur-Landau, Daniel; Martínez-Carrasco, Carlos; Baneth, Gad
2018-05-21
Previous studies have reported nematodes of the Spirocercidae family in the stomach nodules of red foxes (Vulpes vulpes) described as Spirocerca sp. or Spirocerca lupi (Rudolphi, 1819). We characterized spirurid worms collected from red foxes and compared them to S. lupi from domestic dogs by morphometric and phylogenetic analyses. Nematodes from red foxes differed from S. lupi by the presence of six triangular teeth-like buccal capsule structures, which are absent in the latter. Additionally, in female worms from red foxes, the distance of the vulva opening to the anterior end and the ratio of the glandular-to-muscular oesophagus lengths were larger than those of S. lupi (P < 0.006). In males, the lengths of the whole oesophagus and glandular part, the ratio of the glandular-to-muscular oesophagus and the comparison of the oesophagus to the total body length were smaller in S. lupi (all P < 0.044). Phylogenetic analyses revealed that S. lupi and the red foxes spirurid represent monophyletic sister groups with pairwise nucleotide distances of 9.2 and 0.2% in the cytochrome oxidase 1 and 18S genes, respectively. Based on these comparisons, the nematodes from red foxes were considered to belong to a separate species, for which the name Spirocerca vulpis sp. nov. is proposed.
Wakabayashi, Kamila A L; de Melo, Nathalya I; Aguiar, Daniela P; de Oliveira, Pollyanna F; Groppo, Milton; da Silva Filho, Ademar A; Rodrigues, Vanderlei; Cunha, Wilson R; Tavares, Denise C; Magalhães, Lizandra G; Crotti, Antônio E M
2015-07-01
Foeniculum vulgare Mill. (Apiaceae), known as fennel, is a widespread aromatic herbaceous plant, and its essential oil is used as additive in the food, pharmaceutical, cosmetic, and perfume industries. The in vitro antischistosomal activity and cytotoxic effects against V79 cells of the essential oil of F. vulgare cultivated in southeastern Brazil (FV-EO) was investigated. The FV-EO was obtained by hydrodistillation and characterized by GC-FID and GC/MS analyses. (E)-Anethole (69.8%) and limonene (22.5%) were identified as the major constituents. Its anthelmintic activity against Schistosoma mansoni was evaluated at concentrations of 10, 50, and 100 μg/ml, and it was found to be active against adult S. mansoni worms, although it was less effective than the positive control praziquantel (PZQ) in terms of separation of the coupled pairs, mortality, and decreased motor activity. However, FV-EO elicited an interesting dose-dependent reduction in the number of S. mansoni eggs. On their own, (E)-anethole and the limonene enantiomers were much less effective than FV-EO and PZQ. An XTT-cytotoxicity-based assay evidenced no FV-EO cytotoxicity against V79 cells. In summary, FV-EO displayed moderate in vitro schistosomicidal activity against adult S. mansoni worms, exerted remarkable inhibitory effects on the egg development, and was of low toxicity. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.
Reilly, Douglas K.; Lawler, Daniel E.; Albrecht, Dirk R.; Srinivasan, Jagan
2017-01-01
The use of calcium indicators has greatly enhanced our understanding of neural dynamics and regulation. The nematode Caenorhabditis elegans, with its completely mapped nervous system and transparent anatomy, presents an ideal model for understanding real-time neural dynamics using calcium indicators. In combination with microfluidic technologies and experimental designs, calcium-imaging studies using these indicators are performed in both free-moving and trapped animals. However, most previous studies utilizing trapping devices, such as the olfactory chip described in Chronis et al., have devices designed for use in the more common hermaphrodite, as the less common male is both morphologically and structurally dissimilar. An adapted olfactory chip was designed and fabricated for increased efficiency in male neuronal imaging with using young adult animals. A turn was incorporated into the worm loading port to rotate the animals and to allow for the separation of the individual neurons within a bilateral pair in 2D imaging. Worms are exposed to a controlled flow of odorant within the microfluidic device, as described in previous hermaphrodite studies. Calcium transients are then analyzed using the open-source software ImageJ. The procedure described herein should allow for an increased amount of male-based C. elegans calcium imaging studies, deepening our understanding of the mechanisms of sex-specific neuronal signaling. PMID:28930991
An analysis of age-prevalence data by catalytic models
Hairston, Nelson G.
1965-01-01
The analysis of age-prevalence curves obtained from bilharziasis surveys is not usually carried out to the maximum depth the data allow for. With a view to obtaining greater value from the available information, the author analyses age-prevalence data for three common human schistosomes by Muench's catalytic models. The two-stage model is found the most appropriate. Use of this model assumes constant rates of becoming positive and of becoming negative. Two separate analyses are required, one for the first few years of life of the human host and one for the remainder. Satisfactory fits to the data are obtained only when the proportion of older people who remain positive is determined. This proportion varies with the intensity of transmission. The calculated rates of becoming positive agree very well with rates obtained by observing originally negative children for 12 months or longer. The parameters in the model are used in interpreting data from skin-test surveys. It is concluded tentatively that in order to be positive by the skin test, a person must have had both sexes of worms at some time in the past and to be carrying living female worms or to have been exposed recently to female cercariae. It may become possible to use the model to predict the entire age-prevalence curve from data on children, thus saving much effort in parasitological surveys. PMID:5294588
Environmental Assessment Tent City at Grand Forks AFB, North Dakota
2004-11-15
animals such as sponges, flatworms, nematode worms, segmented worms, snails, clams, and immature and adult insects , fish, amphibians, turtles, and... nettle (Laportea canadensis), stinging nettle (Urtica dioica), beggars’ ticks (Bidens frondosa), and waterleaf (Hydrophyllum viginianum) are
Code of Federal Regulations, 2013 CFR
2013-01-01
..., free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and free from..., CERTIFICATION, AND STANDARDS) United States Standards for Pears for Canning Grades § 51.1347 U.S. No. 2. “U.S...
Code of Federal Regulations, 2014 CFR
2014-01-01
..., free from scald, hard end, black end, internal breakdown, decay, worms and worm holes, and free from..., CERTIFICATION, AND STANDARDS) United States Standards for Pears for Canning Grades § 51.1347 U.S. No. 2. “U.S...
Code of Federal Regulations, 2014 CFR
2014-01-01
... scald, hard end, black end, internal breakdown, decay, worms and worm holes, and from damage caused by..., CERTIFICATION, AND STANDARDS) United States Standards for Pears for Canning Grades § 51.1346 U.S. No. 1. “U.S...
Code of Federal Regulations, 2013 CFR
2013-01-01
... scald, hard end, black end, internal breakdown, decay, worms and worm holes, and from damage caused by..., CERTIFICATION, AND STANDARDS) United States Standards for Pears for Canning Grades § 51.1346 U.S. No. 1. “U.S...
Keep the Worms Out of Your Pet's Heart! The Facts About Heartworm Disease
... in all 50 states. The Heartworm Lifecycle in Dogs In an infected dog, adult female heartworms release ... from 1 to 250 worms. How is a Dog Tested for Heartworms? A veterinarian uses blood tests ...
Platt, Thomas R; Zelmer, Derek A
2016-02-01
The course of infection of Echinostoma caproni was followed in female ICR mice, a permissive laboratory host, from infection to natural termination. Twenty-one mice were infected with 20 metacercariae via oral intubation and housed 3 per cage. Three mice from a randomly selected cage were necropsied at 1 mo intervals. A second group of 15 mice was infected approximately 1 yr later to replace mice negative at necropsy in the first group. Mice in the second group were examined weekly for the presence of eggs in the feces. Mice negative for eggs on consecutive days were killed and necropsied. The location of individual worms and worm clusters were located in 20 segments of the small intestine. Adult worms were killed and fixed in hot formalin, stained, and prepared as whole mounts. Standard measurements were taken using a compound microscope fitted with an ocular micrometer. The infection spontaneously resolved in 10 mice from 7 to 32 wk PI, indicating the host response is highly variable and extending the maximum recorded length of E. caproni infections in ICR mice to 31 wk. A moribund worm was found in the feces of an animal that continued to pass eggs for an additional 2 mo indicating individual variation in worm responses. Worms located preferentially in the ileum (segments 11-13) during the first 3 mo of the infection but shifted to the jejunum (segments 8-9) during weeks 4-6. Morphologically, worms of different ages clustered together in multivariate space, with substantial overlap between the 3- and 4-mo-old infrapopulations and between the 5- and 6-mo-old infrapopulations. Muscular structures increased in size throughout the experiment, while the gonads increased in size for the first 3 mo and then declined during the last 3 mo. The relationship between E. caproni and ICR mice is more nuanced than previously reported. The reduction in gonad size and the shift from the ileum to the jejunum in the last 3 mo likely are related. These changes might be attributable to a localized immune response by mice to E. caproni that results in the ileum becoming less hospitable and a resultant relocation of the worms to a less favorable location in the jejunum.
Wang, Sheng-ye; Tang, Yan-kui; Li, Kun; Mo, Ya-yuan; Li, Hao-feng; Gu, Zhan-qi
2014-12-01
Magnetic biochar was prepared with eucalyptus leaf residue remained after essential oil being extracted. Batch experiments were conducted to examine the capacity of the magnetic biochar to remove Cr (VI) from electroplating wastewater and to be separated by an external magnetic field. The results show that the initial solution pH plays an important role on both sorption and separation. The removal rates of Cr (VI), total Cr, Cu (II), and Ni (II) were 97.11%, 97.63%, 100% and 100%, respectively. The turbidity of the sorption-treated solution was reduced to 21.8NTU from 4075NTU after 10min magnetic separation. The study also confirms that the magnetic biochar still retains the original magnetic separation performance after the sorption process. Copyright © 2014 Elsevier Ltd. All rights reserved.
Zhou, Yang; Li, Yuan; Li, Cheng; Liu, Lu; Zhang, Tingting
2013-11-01
To study the inhibition of welsh onion on Microcystis aeruginosa, and separat and identify of the allelochemicals from welsh onion. METHEDS: The inhibitory effect of different concentrations of fistular onion stalk and fistular onion leaf water extracts on M. aeruginosa were studied; besides, separation and identification of the allelochemicals of welsh onion were also studied. Both fistular onion stalk and fistular onion leaf water extracts had, to different degree, inhibitory effect on the growth of M. aeruginosat. Compared with the control group, the fluorescence intensity of fistular onion stalk and fistular onion leaf were lower than the control group in the same period, and the inhibitory effect were more obvious with the increase of the water extract concentrations, to the fifth day, M. aeruginosa almost completely dead of the highest concentration(50 ml/L) of fistular onion stalk water extract treated group, the EC50 of water extract from fistular onion stalk to M. aeruginosa was 12.7 ml/L, equivalent to fresh weight 1.27 g/L. Main allelochemicals in fistular onion stalk includes allyl mercaptan, cyclopentyl mercaptan, and so on. The inhibiting assay on M. aeruginosa showed that the EC50 of allyl mercaptan and cyclopentyl mercaptan respectively were 0.03 and 0.02 g/L. The fistular onion stalk water extracts has very good algicidal effect, allelopathic algal inhibiting substances primarily are sulfocompound, which have the potential to develop into biological algicide.
NASA Astrophysics Data System (ADS)
Filley, T. R.; Altmann, J.; Szlavecz, K. A.; Kalbitz, K.; Gamblin, D.; Nierop, K.
2012-12-01
The physical and microbial transformation of plant detritus in the litter layer and soil is accompanied by chemical separation of progressively soluble fractions and their movement into the rhizosphere driving subsequent soil processes. We investigated the combined action of specific detritivores, microbial decay, and leaching on the chemical separation of plant aromatic and aliphatic components from root, wood, and leaf tissue using 13C-TMAH thermochemolysis. This method enabled the simultaneous analysis of hydrolyzable tannin and lignin fragments, substituted fatty acids, and condensed tannin composition and revealed process-specific chemical transformations to plant secondary compounds. Long-term incubation and field sampling demonstrated how plant residues are progressively leached of the water soluble, oxidized fragments generated through decay. The residues appeared only slightly altered, in the case of brown rot wood, or enriched in aliphatic fragments, in the case of leaf and root tissue. Water extractable fractions were always selectively dominated by polyphenolics, either as demethylated lignin or tannins, and nearly devoid of aliphatic materials, despite high concentrations in the starting materials. Additionally, for plant materials with high tannin contents, such as pine needles, consumption and passage through some arthropod guts revealed what appeared to be microbially-mediated methylation of phenols, and a loss of tannins in leachates. These findings are indications for an in-situ phenol detoxification mechanism. This research provides important information regarding the links between biochemical decay and the chemical nature of organic matter removed and remaining in the soil profile.
Code of Federal Regulations, 2014 CFR
2014-04-01
... is used as an anthelmintic in cattle for treatment of the following parasites: stomach worms... used as an anthelmintic in cattle for treatment of the following parasites: stomach worms (Haemonchus... site. Cattle that are severely parasitized or maintained under conditions of constant helminth exposure...
Lepidoptera associated with western spruce budworm: introduction
Robert E. Stevens; V. M. Carolin; George P. Markin
1984-01-01
Field workers doing surveys, control operations, and research on western spruce bud worm often encounter other kinds of foliage-feeding larvae, some of which closely resemble western spruce bud worm , Workers must be able to distinguish between the different species and groups.
The Worm Guide: A Vericomposting Guide for Teachers.
ERIC Educational Resources Information Center
California Integrated Waste Management Board, Sacramento.
This guide focuses on vermicomposting of food waste. Contents include: (1) "Integrated Waste Management"; (2) "Basics of Vermicomposting"; (3) "Other Worm Bin Residents"; (4) "The Garden Connection"; (5) "Closing the Food Loop at Your School"; (6) "Fundraising"; (7) "Activities for…
Dioctophymiasis: A Rare Case Report.
Chauhan, Sapna; Kaval, Sunil; Tewari, Swati
2016-02-01
Dioctophyma renale commonly known as "giant kidney worm' is found in the kidney of carnivorous mammals. Human infestation is rare, but results in destruction of the kidneys. Very few cases have been reported worldwide. We are here reporting a case of Dioctophymiasis in a 35-year-old male patient who presented with retention of urine and subsequent passage of worm and blood in urine. The worm was confirmed as Dioctophyma renale based on its morphology and clinical presentation. This is a very rare case report and to best of our knowledge only two cases have been reported from India.
Shells, holes, worms, high-velocity gas and the z-distribution of gas in galaxies.
NASA Astrophysics Data System (ADS)
Rand, R. J.
The author gives an overview of the current observational understanding of vertically extended gas components in spiral galaxies and the various phenomena which come under such names as shells, holes, worms, and high-velocity gas. For the most part, the focus is on recent high-resolution interferometric studies. The author concentrates on cold gas, and briefly on warm ionized gas, in the Milky Way and a few nearby spirals. Along the way, it is seen how phenomena such as worms and shells may be related to the formation and maintenance of the vertically extended components.
Fernández-Gómez, Manuel J; Romero, Esperanza; Nogales, Rogelio
2011-09-15
Pesticide application in agriculture causes residues in post-harvest plant waste at different concentrations. Knowledge concerning how pesticide concentrations in such waste affect earthworms is essential for recycling greenhouse plant debris through vermicomposting. Here, we have evaluated the effects of imidacloprid (IMD) residues on earthworms (Eisenia fetida) during the vermicomposting of plant waste from greenhouse crops in Spain. Before, the effect of different IMD concentrations on earthworms was tested using cattle manure as an optimum waste for worm development. The results after using cattle manure indicate that IMD dose ≥ 5 mg kg(-1) hinders worm growth and even causes death, whereas IMD dose ≤ 2 mg IMD kg(-1) allows worm growth similar to control but impedes reproduction. The results from the vermicomposting of plant waste reveal that IMD inhibits adequate worm growth and increases mortality. Although 89% worms became sexually mature in substrate containing 2 mg IMD kg(-1), they did not produce cocoons. IMD also affected microorganisms harboured in the substrates for vermicomposting, as indicated by the reduction in their dehydrogenase activity. This enzyme activity was restored after vermicomposting. This study provides a sound basis for the vermicomposting of pesticide-contaminated plant waste. Copyright © 2011 Elsevier B.V. All rights reserved.
Dynamics of asexual reproduction in flatworms
NASA Astrophysics Data System (ADS)
Schoetz, Eva-Maria; Talbot, Jared; Dunkel, Joern
2010-03-01
Planarians (flatworms) are one of the simplest bilaterally symmetric organisms and famous for their extraordinary regenerative capabilities. One can cut a worm in 100 pieces and after a few weeks one obtains 100 new worms that have reconstructed their entire body, including a central nervous system. This amazing regenerative capability is due to a population of stem cells distributed throughout the planarian body. These stem cells do not only allow the worms to heal without scarring after wounding, they also allow for asexual reproduction: Planarians can split themselves in two, and then regenerate the missing body parts within about a week. Naively, one would think that this kind of asexual reproduction could be captured by simple models that describe cell growth in bacteria or other lower organisms. However, we find that there is much more to the story by monitoring >15 generations of many individuals, as well as the long-term behavior (> 9 months) of worm populations under different environmental conditions, such as population density, temperature, and feeding frequency. Surprisingly, we observe that reproduction decreases with increasing food supply, opposite to the relationship between food and reproduction in other asexually reproducing organisms (e.g. bacteria, yeast), and causing obese worms. Finally, our data allows us to address the question of aging in an organism that is thought to be ``forever young''.
Stotz, Henrik U.; Pittendrigh, Barry R.; Kroymann, Jürgen; Weniger, Kerstin; Fritsche, Jacqueline; Bauke, Antje; Mitchell-Olds, Thomas
2000-01-01
The induction of plant defenses by insect feeding is regulated via multiple signaling cascades. One of them, ethylene signaling, increases susceptibility of Arabidopsis to the generalist herbivore Egyptian cotton worm (Spodoptera littoralis; Lepidoptera: Noctuidae). The hookless1 mutation, which affects a downstream component of ethylene signaling, conferred resistance to Egyptian cotton worm as compared with wild-type plants. Likewise, ein2, a mutant in a central component of the ethylene signaling pathway, caused enhanced resistance to Egyptian cotton worm that was similar in magnitude to hookless1. Moreover, pretreatment of plants with ethephon (2-chloroethanephosphonic acid), a chemical that releases ethylene, elevated plant susceptibility to Egyptian cotton worm. By contrast, these mutations in the ethylene-signaling pathway had no detectable effects on diamondback moth (Plutella xylostella) feeding. It is surprising that this is not due to nonactivation of defense signaling, because diamondback moth does induce genes that relate to wound-response pathways. Of these wound-related genes, jasmonic acid regulates a novel β-glucosidase 1 (BGL1), whereas ethylene controls a putative calcium-binding elongation factor hand protein. These results suggest that a specialist insect herbivore triggers general wound-response pathways in Arabidopsis but, unlike a generalist herbivore, does not react to ethylene-mediated physiological changes. PMID:11080278
Rajapakse, R P V J; Iwagami, M; Wickramasinghe, S; Walker, S M; Agatsuma, T
2013-09-01
Bivitellobilharzia nairi was first recorded from an Indian elephant (Elephas maximus) in Berlin. Infections with this parasite have become increasingly important in E. maximus maximus populations in Sri Lanka. The present work is the first morphological description of this schistosome from Sri Lanka. A number of adult worms were recovered from a dead Asian elephant near the elephant orphanage, Pinnawala, in Sri Lanka. The observed clinical features of the infected elephant included emaciation, subventral oedema and anaemia. Post-mortem results indicated that the liver was enlarged and adult schistosomes were found in the blood vessels of the liver parenchyma. The total number of worms recovered from a portion of the liver was 129,870, which is an average of 22 worms per 100 g of liver. The present study uses both light microscopic and scanning electron microscope (SEM) techniques for the morphological and topographical characterization of this parasite and to permit comparison with other species of schistosomes. Morphologically, these worms correspond very well to the description of B. nairi by Dutt & Srivastava (1955). Moreover, it is clear that B. nairi is a distinctive species easily differentiated from other schistosomes. The SEM study of the tegument of male worms shows that the surface of B. nairi is smoother than in other schistosomes.
Galleria mellonella larvae as an infection model for group A streptococcus
Loh, Jacelyn MS; Adenwalla, Nazneen; Wiles, Siouxsie; Proft, Thomas
2013-01-01
Group A streptococcus is a strict human pathogen that can cause a wide range of diseases, such as tonsillitis, impetigo, necrotizing fasciitis, toxic shock, and acute rheumatic fever. Modeling human diseases in animals is complicated, and rapid, simple, and cost-effective in vivo models of GAS infection are clearly lacking. Recently, the use of non-mammalian models to model human disease is starting to re-attract attention. Galleria mellonella larvae, also known as wax worms, have been investigated for modeling a number of bacterial pathogens, and have been shown to be a useful model to study pathogenesis of the M3 serotype of GAS. In this study we provide further evidence of the validity of the wax worm model by testing different GAS M-types, as well as investigating the effect of bacterial growth phase and incubation temperature on GAS virulence in this model. In contrast to previous studies, we show that the M-protein, among others, is an important virulence factor that can be effectively modeled in the wax worm. We also highlight the need for a more in-depth investigation of the effects of experimental design and wax worm supply before we can properly vindicate the wax worm model for studying GAS pathogenesis. PMID:23652836
A new approach to modelling schistosomiasis transmission based on stratified worm burden.
Gurarie, D; King, C H; Wang, X
2010-11-01
Multiple factors affect schistosomiasis transmission in distributed meta-population systems including age, behaviour, and environment. The traditional approach to modelling macroparasite transmission often exploits the 'mean worm burden' (MWB) formulation for human hosts. However, typical worm distribution in humans is overdispersed, and classic models either ignore this characteristic or make ad hoc assumptions about its pattern (e.g., by assuming a negative binomial distribution). Such oversimplifications can give wrong predictions for the impact of control interventions. We propose a new modelling approach to macro-parasite transmission by stratifying human populations according to worm burden, and replacing MWB dynamics with that of 'population strata'. We developed proper calibration procedures for such multi-component systems, based on typical epidemiological and demographic field data, and implemented them using Wolfram Mathematica. Model programming and calibration proved to be straightforward. Our calibrated system provided good agreement with the individual level field data from the Msambweni region of eastern Kenya. The Stratified Worm Burden (SWB) approach offers many advantages, in that it accounts naturally for overdispersion and accommodates other important factors and measures of human infection and demographics. Future work will apply this model and methodology to evaluate innovative control intervention strategies, including expanded drug treatment programmes proposed by the World Health Organization and its partners.
Worm infestation and anaemia among pre-school children of peasant farmers in Calabar, Nigeria.
Anah, M U; Ikpeme, O E; Etuk, I S; Yong, K E; Ibanga, I; Asuquo, B E
2008-09-01
Worm infection and anaemia are common childhood conditions in Nigeria. We assessed the status of helminthiasis and associated anaemia among pre school children of peasant farmers aged 1-5 years living in a rubber plantation near Calabar, Nigeria. Cross sectional. Three hundred and fifty children were selected by multi-stage cluster sampling technique. Freshly passed stool was examined using Kato-Katz method while anaemia was estimated using haematocrit technique. Of the 350 children, 174 (49.7%) had intestinal helminths: Ascaris lumbricoides 64.4%, hookworms 10.9% and Trichuris trichuria 1.1%. There were 41(23.6%) children with polyparasitism, 33 of them were due to Ascaris lumbricoides and hookworms. The worm load was generally light in intensity with egg per gram of stool ranging from 24-60,960. Males (28.9%) were infected more than females (20.8%). The frequency of infection increases with age. The prevalence of anaemia among the entire study population and in those infected with worms was 56.6% and 56.9% respectively. With polyparasitism there was a relative increase in the frequency of anaemia females > males. Worm infections and anaemia are common in our children. A comprehensive control strategy involving good sanitation, sinking of bore hole for clean water supply and regular deworming exercises are recommended.
NASA Astrophysics Data System (ADS)
Jung, Jaehoon; Nakajima, Masahiro; Masaru, Takeuchi; Huang, Qiang; Fukuda, Toshio
2014-03-01
In this paper, we report on a microfluidic device with a multi-valve system to conduct several exposure tests on Caenorhabditis elegans (C. elegans) simultaneously. It has pneumatic valves and no-moving-parts (NMP) valves. An NMP valve is incorporated with a chamber and enables the unidirectional movement of C. elegans in the chamber; once worms are loaded into the chamber, they cannot exit, regardless of the flow direction. To demonstrate the ability of the NMP valve to handle worms, we made a microfluidic device with three chambers. Each chamber was used to expose worms to Cd and Cu solutions, and K-medium. A pair of electrodes was installed in the device and the capacitance in-between the electrode was measured. When a C. elegans passed through the electrodes, the capacitance was changed. The capacitance change was proportional to the body volume of the worm, thus the body volume change by the heavy metal exposure was measured in the device. Thirty worms were divided into three groups and exposed to each solution. We confirmed that the different solutions induced differences in the capacitance changes for each group. These results indicate that our device is a viable method for simultaneously analyzing the effect of multiple stimuli on C. elegans.
Chan, Io Long; Rando, Oliver J; Conine, Colin C
2018-05-04
Bleaching gravid C. elegans followed by a short period of starvation of the L1 larvae is a routine method performed by worm researchers for generating synchronous populations for experiments. During the process of investigating dietary effects on gene regulation in L1 stage worms by single-worm RNA-Seq, we found that the density of resuspended L1 larvae affects expression of many mRNAs. Specifically, a number of genes related to metabolism and signaling are highly expressed in worms arrested at low density, but are repressed at higher arrest densities. We generated a GFP reporter strain based on one of the most density-dependent genes in our dataset - lips-15 - and confirmed that this reporter was expressed specifically in worms arrested at relatively low density. Finally, we show that conditioned media from high density L1 cultures was able to downregulate lips-15 even in L1 animals arrested at low density, and experiments using daf-22 mutant animals demonstrated that this effect is not mediated by the ascaroside family of signaling pheromones. Together, our data implicate a soluble signaling molecule in density sensing by L1 stage C. elegans , and provide guidance for design of experiments focused on early developmental gene regulation. Copyright © 2018 Chan et al.
Cold-adapted tubulins in the glacier ice worm, Mesenchytraeus solifugus.
Tartaglia, Lawrence J; Shain, Daniel H
2008-11-01
Glacier ice worms, Mesenchytraeus solifugus and related species, are the only known annelids that survive obligately in glacier ice and snow. One fundamental component of cold temperature adaptation is the ability to polymerize tubulin, which typically depolymerizes at low physiological temperatures (e.g., <10 degrees C) in most temperate species. In this study, we isolated two alpha-tubulin (Msalpha1, Msalpha2) and two beta-tubulin (Msbeta1, Msbeta2) subunits from an ice worm cDNA library, and compared their predicted amino acid sequences with homologues from other cold-adapted organisms (e.g., Antarctic fish, ciliate) in an effort to identify species-specific amino acid substitutions that contribute to cold temperature-dependent tubulin polymerization. Our comparisons and predicted protein structures suggest that ice worm-specific amino acid substitutions stabilize lateral contact associations, particularly between beta-tubulin protofilaments, but these substitutions occur at different positions in comparison with other cold-adapted tubulins. The ice worm tubulin gene family appears relatively small, comprising one primary alpha- and one primary beta-tubulin monomers, though minor isoforms and pseudogenes were identified. Our analyses suggest that variation occurs in the strategies (i.e., species-specific amino acid substitutions, gene number) by which cold-adapted taxa have evolved the ability to polymerize tubulin at low physiological temperatures.
Tang, Lei; Wang, Chenchen; Huang, Jiabao; Zhang, Jianhua; Mao, Zhonggui; Wang, Haiou
2013-01-15
Plant peroxidases (EC 1.11.1.7) with different isoforms catalyze various reactions in plant growth and development. However, it is difficult to elucidate the function of each isozyme in one plant. Here, we compared profiles of entire isozyme in young seedling and mature leaves of Chinese kale (Brassica alboglabra L.) on zymogram and ion exchange chromatography in order to investigate leaf growth related peroxidase isozymes. The results showed that four isozymes were constitutively expressed in kale leaves, whereas other two isozymes were induced in the mature leaves. The Mono Q ion exchange chromatography separated the six isozymes into two major groups due to the difference in their isoelectric points. The results suggested that although there were several isozymes in the leaves of Chinese kale, one isozyme functioned mainly through the leaf development. Two anionic isozymes with molecular weights lower than 32 kDa were considered mature related. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Al Farishy, D. D.; Nisyawati, Metusala, D.
2017-07-01
Nepenthes is one of carnivorous plant genera which have key characters on leaf and pitcher as the modification. However, wide varieties of morphological features on pitcher intraspecies and between species could be tough for identification process. The objective was to provide alternative characters for identification process by anatomical features. Kerinci Seblat National Park was chosen because lack of update data on wild type of species there. Whole five species were collected at Lingkat Lake and Gunung Tujuh Lake as representative lowland and highland species. Leaves collected fresh, flawless, and has grown pitcher. Each leaf was separated into the paradermal and transversal section, dehydrated by series alcohol, and stained by safranin and fast green. Sections observed by light microscope. Result show there were specific differences between species that could be potential to be key characters. That features are stomatal density, stomatal length, sessile glands surface shaped, sessile glands density, trichome distribution, adaxial cuticle thickness, adaxial hypodermic thickness, and the number of layers of adaxial hypodermis
Cambridge, M L; Zavala-Perez, A; Cawthray, G R; Mondon, J; Kendrick, G A
2017-02-15
Highly saline brines from desalination plants expose seagrass communities to salt stress. We examined effects of raised salinity (46 and 54psu) compared with seawater controls (37psu) over 6weeks on the seagrass, Posidonia australis, growing in tanks with the aim of separating effects of salinity from other potentially deleterious components of brine and determining appropriate bioindicators. Plants survived exposures of 2-4weeks at 54psu, the maximum salinity of brine released from a nearby desalination plant. Salinity significantly reduced maximum quantum yield of PSII (chlorophyll a fluorescence emissions). Leaf water potential (Ψ w ) and osmotic potential (Ψ π ) were more negative at increased salinity, while turgor pressure (Ψ p ) was unaffected. Leaf concentrations of K + and Ca 2+ decreased, whereas concentrations of sugars (mainly sucrose) and amino acids increased. We recommend leaf osmolarity, ion, sugar and amino acid concentrations as bioindicators for salinity effects, associated with brine released in desalination plant outfalls. Copyright © 2016 Elsevier Ltd. All rights reserved.
Leaf water stress detection utilizing thematic mapper bands 3, 4 and 5 in soybean plants
NASA Technical Reports Server (NTRS)
Holben, B. N.; Schutt, J. B.; Mcmurtrey, J., III
1983-01-01
The total and diffuse radiance responses of Thematic Mapper bands 3 (0.63-0.69 microns), 4 (0.76-0.90 microns), and 5 (1.55-1.75 microns) to water stress in a soybean canopy are compared. Polarization measurements were used to separate the total from the diffuse reflectance; the reflectances were compared statistically at a variety of look angles at 15 min intervals from about 09.00 until 14.00 hrs EST. The results suggest that remotely sensed data collected in the photographic infrared region (TM4) are sensitive to leaf water stress in a 100 percent canopy cover of soybeans, and that TM3 is less sensitive than TM4 for detection of reversible foliar water stress. The mean values of TM5 reflectance data show similar trends to TM4. The primary implication of this study is that remote sensing of water stress in green plant canopies is possible in TM4 from ground-based observations primarily through the indirect link of leaf geometry.
USDA-ARS?s Scientific Manuscript database
During 2011-2013 plants of the invasive weed species Alliaria petiolata (garlic mustard) were observed with virus-like disease symptoms in three separate locations in Ramsey and Anoka counties, Minnesota. Symptoms consisted of conspicuous mosaic, leaf deformation and stunting. Numerous virus-like pa...
NASA Astrophysics Data System (ADS)
Calderer, Antoni; Neal, Douglas; Prevost, Richard; Mayrhofer, Arno; Lawrenz, Alan; Foss, John; Sotiropoulos, Fotis
2015-11-01
Secondary flows in a rotating flow in a cylinder, resulting in the so called ``tea leaf paradox'', are fundamental for understanding atmospheric pressure systems, developing techniques for separating red blood cells from the plasma, and even separating coagulated trub in the beer brewing process. We seek to gain deeper insights in this phenomenon by integrating numerical simulations and experiments. We employ the Curvilinear Immersed boundary method (CURVIB) of Calderer et al. (J. Comp. Physics 2014), which is a two-phase flow solver based on the level set method, to simulate rotating free-surface flow in a cylinder partially filled with water as in the tea leave paradox flow. We first demonstrate the validity of the numerical model by simulating a cylinder with a rotating base filled with a single fluid, obtaining results in excellent agreement with available experimental data. Then, we present results for the cylinder case with free surface, investigate the complex formation of secondary flow patterns, and show comparisons with new experimental data for this flow obtained by Lavision. Computational resources were provided by the Minnesota Supercomputing Institute.
Cai, Di; Li, Ping; Luo, Zhangfeng; Qin, Peiyong; Chen, Changjing; Wang, Yong; Wang, Zheng; Tan, Tianwei
2016-07-01
To investigate the effect of dilute alkaline pretreatment on different parts of biomass, corn stalk was separated into flower, leaf, cob, husk and stem, which were treated by NaOH in range of temperature and chemical loading. The NaOH-pretreated solid was then enzymatic hydrolysis and used as the substrate for batch acetone-butanol-ethanol (ABE) fermentation. The results demonstrated the five parts of corn stalk could be used as potential feedstock separately, with vivid performances in solvents production. Under the optimized conditions towards high product titer, 7.5g/L, 7.6g/L, 9.4g/L, 7g/L and 7.6g/L of butanol was obtained in the fermentation broth of flower, leaf, cob, husk and stem hydrolysate, respectively. Under the optimized conditions towards high product yield, 143.7g/kg, 126.3g/kg, 169.1g/kg, 107.7g/kg and 116.4g/kg of ABE solvent were generated, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kielar, Kayla N; Mok, Ed; Hsu, Annie; Wang, Lei; Luxton, Gary
2012-10-01
The dosimetric leaf gap (DLG) in the Varian Eclipse treatment planning system is determined during commissioning and is used to model the effect of the rounded leaf-end of the multileaf collimator (MLC). This parameter attempts to model the physical difference between the radiation and light field and account for inherent leakage between leaf tips. With the increased use of single fraction high dose treatments requiring larger monitor units comes an enhanced concern in the accuracy of leakage calculations, as it accounts for much of the patient dose. This study serves to verify the dosimetric accuracy of the algorithm used to model the rounded leaf effect for the TrueBeam STx, and describes a methodology for determining best-practice parameter values, given the novel capabilities of the linear accelerator such as flattening filter free (FFF) treatments and a high definition MLC (HDMLC). During commissioning, the nominal MLC position was verified and the DLG parameter was determined using MLC-defined field sizes and moving gap tests, as is common in clinical testing. Treatment plans were created, and the DLG was optimized to achieve less than 1% difference between measured and calculated dose. The DLG value found was tested on treatment plans for all energies (6 MV, 10 MV, 15 MV, 6 MV FFF, 10 MV FFF) and modalities (3D conventional, IMRT, conformal arc, VMAT) available on the TrueBeam STx. The DLG parameter found during the initial MLC testing did not match the leaf gap modeling parameter that provided the most accurate dose delivery in clinical treatment plans. Using the physical leaf gap size as the DLG for the HDMLC can lead to 5% differences in measured and calculated doses. Separate optimization of the DLG parameter using end-to-end tests must be performed to ensure dosimetric accuracy in the modeling of the rounded leaf ends for the Eclipse treatment planning system. The difference in leaf gap modeling versus physical leaf gap dimensions is more pronounced in the more recent versions of Eclipse for both the HDMLC and the Millennium MLC. Once properly commissioned and tested using a methodology based on treatment plan verification, Eclipse is able to accurately model radiation dose delivered for SBRT treatments using the TrueBeam STx.
[Latitudinal Changes in Plant Stoichiometric and Soil C, N, P Stoichiometry in Loess Plateau].
Li, Ting; Deng, Qiang; Yuan, Zhi-you; Jiao, Feng
2015-08-01
Field investigations and sampling were conducted in Loess Plateau, including Fu County, Ganquan County, Ansai County, Jingbian County and Hengshan County and Yuyang District. Our objective was to examine changes of leaf and soil stoichiometry characteristics along latitudinal gradient in Loess Plateau, and to provide references for the prediction of soil nutrient status of the ecosystem and constraints of plant nutrition elements in Loess Plateau. The results showed that (1) Across the 35.95 degrees-38.36 degrees N latitude gradient, leaf C, N and P stoichiometry were ranging from 336.95 to 477.38 mg x g(-1) for C, from 18.09 to 33.173 mg x g(-1) for N and from 1.07 to 1.73 mg x g(-1) for P, the arithmetic means were 442.9 mg x g(-1), 25.79 mg x g(-1) and 1.37 mg x g(-1), separately, the variation coefficients were 11.9%, 17.4% and 13.3%. There were obvious correlation between leaf C, N, P and latitude, leaf C, C : N ratio and C: P ratio significantly decreased with the increasing latitude, while leaf N and P significantly increased with the increasing latitude. The relationship between N: P ratio and latitude was not significant. (2) The content of soil organic C and soil total N decreased with increasing latitude and soil layer. In contrast, with the increase of latitude, soil P increased and then decreased. In the 0-10 cm, 10-20 cm soil layers, soil C: N ratio did not change significantly with latitude, while in the 20-40 cm layer, C: N ratio decreased obviously, but soil C: P and N: P ratios decreased with the increasing latitude in all soil layers. (3) Leaf C, C: N and C: P ratios were correlated to soil organic C, soil total N and soil total P in all soil layers, leaf N and P were correlated to soil organic C and soil total N, while leaf N: P ratio was not correlated to soil organic C, soil total N and soil total P. There was a certain correlation between the leaf C, N, P and latitude, however, the correlations between leaf and soil C, N, P were inconsistent. These results demonstrate that the plants were under P limitation in Loess Plateau.
Kazi, S; Shultz, J; Afzal, J; Johnson, J; Njiti, V N; Lightfoot, D A
2008-05-01
Soybean [Glycine max (L.) Merr.] cultivars show differences in their resistance to both the leaf scorch and root rot of sudden death syndrome (SDS). The syndrome is caused by root colonization by Fusarium virguliforme (ex. F. solani f. sp. glycines). Root susceptibility combined with reduced leaf scorch resistance has been associated with resistance to Heterodera glycines HG Type 1.3.6.7 (race 14) of the soybean cyst nematode (SCN). In contrast, the rhg1 locus underlying resistance to Hg Type 0 was found clustered with three loci for resistance to SDS leaf scorch and one for root infection. The aims of this study were to compare the inheritance of resistance to leaf scorch and root infection in a population that segregated for resistance to SCN and to identify the underlying quantitative trait loci (QTL). "Hartwig", a cultivar partially resistant to SDS leaf scorch, F. virguliforme root infection and SCN HG Type 1.3.6.7 was crossed with the partially susceptible cultivar "Flyer". Ninety-two F5-derived recombinant inbred lines and 144 markers were used for map development. Four QTL found in earlier studies were confirmed. One contributed resistance to leaf scorch on linkage group (LG) C2 (Satt277; P = 0.004, R2 = 15%). Two on LG G underlay root infection at R8 (Satt038; P = 0.0001 R2 = 28.1%; Satt115; P = 0.003, R2 = 12.9%). The marker Satt038 was linked to rhg1 underlying resistance to SCN Hg Type 0. The fourth QTL was on LG D2 underlying resistance to root infection at R6 (Satt574; P = 0.001, R2 = 10%). That QTL was in an interval previously associated with resistance to both SDS leaf scorch and SCN Hg Type 1.3.6.7. The QTL showed repulsion linkage with resistance to SCN that may explain the relative susceptibility to SDS of some SCN resistant cultivars. One additional QTL was discovered on LG G underlying resistance to SDS leaf scorch measured by disease index (Satt130; P = 0.003, R2 = 13%). The loci and markers will provide tagged alleles with which to improve the breeding of cultivars combining resistances to SDS leaf scorch, root infection and SCN HG Type 1.3.6.7.
Telford, Maximilian J; Copley, Richard R
2016-04-25
The phylogenetic affinities of Xenacoelomorpha - the phylum comprising Xenoturbella bocki and acoelomorph worms - are debated. Two recent studies conclude they represent the earliest branching bilaterally symmetrical animals, but additional tests may be needed to confirm this notion. Copyright © 2016 Elsevier Ltd. All rights reserved.
Predicting path from undulations for C. elegans using linear and nonlinear resistive force theory
NASA Astrophysics Data System (ADS)
Keaveny, Eric E.; Brown, André E. X.
2017-04-01
A basic issue in the physics of behaviour is the mechanical relationship between an animal and its surroundings. The model nematode C. elegans provides an excellent platform to explore this relationship due to its anatomical simplicity. Nonetheless, the physics of nematode crawling, in which the worm undulates its body to move on a wet surface, is not completely understood and the mathematical models often used to describe this phenomenon are empirical. We confirm that linear resistive force theory, one such empirical model, is effective at predicting a worm’s path from its sequence of body postures for forward crawling, reversing, and turning and for a broad range of different behavioural phenotypes observed in mutant worms. Worms recently isolated from the wild have a higher effective drag anisotropy than the laboratory-adapted strain N2 and most mutant strains. This means the wild isolates crawl with less surface slip, perhaps reflecting more efficient gaits. The drag anisotropies required to fit the observed locomotion data (70 ± 28 for the wild isolates) are significantly larger than the values measured by directly dragging worms along agar surfaces (3-10 in Rabets et al (2014 Biophys. J. 107 1980-7)). A proposed nonlinear extension of the resistive force theory model also provides accurate predictions, but does not resolve the discrepancy between the parameters required to achieve good path prediction and the experimentally measured parameters. We confirm that linear resistive force theory provides a good effective model of worm crawling that can be used in applications such as whole-animal simulations and advanced tracking algorithms, but that the nature of the physical interaction between worms and their most commonly studied laboratory substrate remains unresolved.
WormSizer: high-throughput analysis of nematode size and shape.
Moore, Brad T; Jordan, James M; Baugh, L Ryan
2013-01-01
The fundamental phenotypes of growth rate, size and morphology are the result of complex interactions between genotype and environment. We developed a high-throughput software application, WormSizer, which computes size and shape of nematodes from brightfield images. Existing methods for estimating volume either coarsely model the nematode as a cylinder or assume the worm shape or opacity is invariant. Our estimate is more robust to changes in morphology or optical density as it only assumes radial symmetry. This open source software is written as a plugin for the well-known image-processing framework Fiji/ImageJ. It may therefore be extended easily. We evaluated the technical performance of this framework, and we used it to analyze growth and shape of several canonical Caenorhabditis elegans mutants in a developmental time series. We confirm quantitatively that a Dumpy (Dpy) mutant is short and fat and that a Long (Lon) mutant is long and thin. We show that daf-2 insulin-like receptor mutants are larger than wild-type upon hatching but grow slow, and WormSizer can distinguish dauer larvae from normal larvae. We also show that a Small (Sma) mutant is actually smaller than wild-type at all stages of larval development. WormSizer works with Uncoordinated (Unc) and Roller (Rol) mutants as well, indicating that it can be used with mutants despite behavioral phenotypes. We used our complete data set to perform a power analysis, giving users a sense of how many images are needed to detect different effect sizes. Our analysis confirms and extends on existing phenotypic characterization of well-characterized mutants, demonstrating the utility and robustness of WormSizer.
Tunnicliffe, Verena; St Germain, Candice; Hilário, Ana
2014-01-01
We examine the nature of variation in a hot vent tubeworm, Ridgeia piscesae, to determine how phenotypes are maintained and how reproductive potential is dictated by habitat. This foundation species at northeast Pacific hydrothermal sites occupies a wide habitat range in a highly heterogeneous environment. Where fluids supply high levels of dissolved sulphide for symbionts, the worm grows rapidly in a "short-fat" phenotype characterized by lush gill plumes; when plumes are healthy, sperm package capture is higher. This form can mature within months and has a high fecundity with continuous gamete output and a lifespan of about three years in unstable conditions. Other phenotypes occupy low fluid flux habitats that are more stable and individuals grow very slowly; however, they have low reproductive readiness that is hampered further by small, predator cropped branchiae, thus reducing fertilization and metabolite uptake. Although only the largest worms were measured, only 17% of low flux worms were reproductively competent compared to 91% of high flux worms. A model of reproductive readiness illustrates that tube diameter is a good predictor of reproductive output and that few low flux worms reached critical reproductive size. We postulate that most of the propagules for the vent fields originate from the larger tubeworms that live in small, unstable habitat patches. The large expanses of worms in more stable low flux habitat sustain a small, but long-term, reproductive output. Phenotypic variation is an adaptation that fosters both morphological and physiological responses to differences in chemical milieu and predator pressure. This foundation species forms a metapopulation with variable growth characteristics in a heterogeneous environment where a strategy of phenotypic variation bestows an advantage over specialization.
Tunnicliffe, Verena; St. Germain, Candice; Hilário, Ana
2014-01-01
We examine the nature of variation in a hot vent tubeworm, Ridgeia piscesae, to determine how phenotypes are maintained and how reproductive potential is dictated by habitat. This foundation species at northeast Pacific hydrothermal sites occupies a wide habitat range in a highly heterogeneous environment. Where fluids supply high levels of dissolved sulphide for symbionts, the worm grows rapidly in a “short-fat” phenotype characterized by lush gill plumes; when plumes are healthy, sperm package capture is higher. This form can mature within months and has a high fecundity with continuous gamete output and a lifespan of about three years in unstable conditions. Other phenotypes occupy low fluid flux habitats that are more stable and individuals grow very slowly; however, they have low reproductive readiness that is hampered further by small, predator cropped branchiae, thus reducing fertilization and metabolite uptake. Although only the largest worms were measured, only 17% of low flux worms were reproductively competent compared to 91% of high flux worms. A model of reproductive readiness illustrates that tube diameter is a good predictor of reproductive output and that few low flux worms reached critical reproductive size. We postulate that most of the propagules for the vent fields originate from the larger tubeworms that live in small, unstable habitat patches. The large expanses of worms in more stable low flux habitat sustain a small, but long-term, reproductive output. Phenotypic variation is an adaptation that fosters both morphological and physiological responses to differences in chemical milieu and predator pressure. This foundation species forms a metapopulation with variable growth characteristics in a heterogeneous environment where a strategy of phenotypic variation bestows an advantage over specialization. PMID:25337895
The antibody response to Dracunculus medinensis in an endemic human population of northern Ghana.
Bloch, P; Simonsen, P E; Vennervald, B J
1993-03-01
The serum antibody response (total, and isotypes IgG1, IgG4, IgM, IgA and IgE) to Guinea worm infection was examined in humans from a highly endemic area of northern Ghana by ELISA and SDS-PAGE/Western blot techniques using an adult D. medinensis antigen. Sera were obtained early and late in the peak transmission period, from persons with patent and postpatent infections, as well as from persons from the same endemic area who claimed never to have had Guinea worm infection. To observe for potential cross-reactions in the tests, sera were also obtained from areas with no transmission of Guinea worm from patients with hookworm, O. volvulus and W. bancrofti infections, and from non-infected controls. Sera from persons living in the Guinea worm endemic area reacted extensively with Guinea worm antigen in both tests, and large numbers of bands were produced in the Western blots (up to 35 identified for some sera). For most antibody isotypes, the ELISA absorbance values obtained with sera from the same individuals varied between the two transmission seasons, with the highest titres present towards the end of the peak transmission period. The mean antibody titres for persons in the patent and postpatent infection categories were not significantly different when sera were obtained at the same season of the year. Persons from the endemic area, who claimed never to experience patent infections, also had antibodies to Guinea worm, although at significantly lower mean levels than for the patent and postpatent categories. The highest specificity in the ELISA and the most homogenous Western blots were obtained when detecting for antibodies of the IgG4 isotype.
Wippler, Juliane; Kleiner, Manuel; Lott, Christian; Gruhl, Alexander; Abraham, Paul E; Giannone, Richard J; Young, Jacque C; Hettich, Robert L; Dubilier, Nicole
2016-11-21
The gutless marine worm Olavius algarvensis has a completely reduced digestive and excretory system, and lives in an obligate nutritional symbiosis with bacterial symbionts. While considerable knowledge has been gained of the symbionts, the host has remained largely unstudied. Here, we generated transcriptomes and proteomes of O. algarvensis to better understand how this annelid worm gains nutrition from its symbionts, how it adapted physiologically to a symbiotic lifestyle, and how its innate immune system recognizes and responds to its symbiotic microbiota. Key adaptations to the symbiosis include (i) the expression of gut-specific digestive enzymes despite the absence of a gut, most likely for the digestion of symbionts in the host's epidermal cells; (ii) a modified hemoglobin that may bind hydrogen sulfide produced by two of the worm's symbionts; and (iii) the expression of a very abundant protein for oxygen storage, hemerythrin, that could provide oxygen to the symbionts and the host under anoxic conditions. Additionally, we identified a large repertoire of proteins involved in interactions between the worm's innate immune system and its symbiotic microbiota, such as peptidoglycan recognition proteins, lectins, fibrinogen-related proteins, Toll and scavenger receptors, and antimicrobial proteins. We show how this worm, over the course of evolutionary time, has modified widely-used proteins and changed their expression patterns in adaptation to its symbiotic lifestyle and describe expressed components of the innate immune system in a marine oligochaete. Our results provide further support for the recent realization that animals have evolved within the context of their associations with microbes and that their adaptive responses to symbiotic microbiota have led to biological innovations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsue, S.Y.; Xu, S.T.; He, Y.X.
1984-09-01
Vaccination of Chinese bovines (cattle and buffaloes) against Schistosomiasis japonica with 36 kR gamma-irradiated schistosomula was done for laboratory challenge and for field trials in China. Altogether, 61 bovines were used. All experimental animals were vaccinated 2-3 times with 10,000 irradiated schistosomula per time. For the laboratory challenge, all experimental and control cattle were challenged with 500 normal cercariae and each buffalo, with 2,000 cercariae. The laboratory-challenged bovines were killed after 54-57 days of challenge; the bovines for the field trial in the lightly endemic area, after 5 months in the field; and the bovines for the field trial inmore » the heavily endemic area, after 58-63 days. When the animals were killed, the number of mature worms in the vaccinated (experimental) and non-vaccinated (control) animals was recorded and the percentage of worm reduction in each group was calculated. The first group, consisting of three vaccinated and three non-vaccinated cattle, was given a laboratory challenge; the worm reduction was 71.6%. The second group, consisting of two vaccinated and three non-vaccinated buffaloes, was also given a laboratory challenge; the worm reduction was 74.4%. The third group, consisting of seven vaccinated and eight non-vaccinated buffaloes, was utilized in a field trial in a lightly endemic area; the worm reduction was 75.6%. The fourth group, consisting of eight vaccinated and nine non-vaccinated cattle, and the fifth group, consisting of nine vaccinated and nine non-vaccinated buffaloes, were pastured in a heavily endemic area. The worm reduction was 65.1% in the fourth group and 75.7% in the fifth group.« less
Arctic Climate during Eocene Hyperthermals: Wet Summers on Ellesmere Island?
NASA Astrophysics Data System (ADS)
Greenwood, D. R.; West, C. K.; Basinger, J. F.
2012-12-01
Previous work has shown that during the late Paleocene to middle Eocene, mesothermal conditions (i.e., MAT ~12-15° C) and high precipitation (MAP > 150cm/yr) characterized Arctic climates - an Arctic rain forest. Recent analyses of Arctic Eocene wood stable isotope chemistry are consistent with the annual and seasonal temperature estimates from leaf physiognomy and nearest living relative analogy from fossil plants, including the lack of freezing winters, but is interpreted as showing that there was a summer peak in precipitation - modern analogs are best sought on the summer-wet east coasts (e.g., China, Japan, South Korea) not the winter-wet west coasts of present-day northern temperate continents (e.g., Pacific northwest of North America). Highly seasonal 'monsoon-type' summer-wet precipitation regimes (i.e., summer precip./winter precip. > 3.0) seem to characterize Eocene hyperthermal conditions in several regions of the earth, including the Arctic and Antarctic, based on both climate model sensitivity experiments and the paleoclimate proxy evidence. The leaf physiognomy proxy previously applied to estimate Arctic Paleogene precipitation was leaf area analysis (LAA), a correlation between mean leaf size in woody dicot vegetation and annual precipitation. New data from modern monsoonal sites, however demonstrates that for deciduous-dicot dominated vegetation, summer precipitation determines mean leaf size, not annual totals, and therefore that under markedly seasonal precipitation and/or light regimes that summer precipitation is being estimated using LAA. Presented here is a new analysis of a leaf macrofloras from 3 separate florules of the Margaret Formation (Split Lake, Stenkul Fiord and Strathcona Fiord) from Ellesmere Island that are placed stratigraphically as early Eocene, and likely fall within Eocene thermal maximum 1 (ETM1; = the 'PETM') or ETM2. These floras are each characterized by a mix of large-leafed and small-leafed dicot taxa, with overall mean leaf size across all leaf morphotypes comparable to that previously reported for late Paleocene to middle Eocene floras from Ellesmere and Axel Heiberg islands of Nunavut. Applying the conventional leaf area analysis to the putatively ETM1 floras yielded estimates of mean annual precipitation 100-200cm/yr, consistent with the previous reports for the late Paleocene to middle Eocene. CLAMP analysis applied to these floras yields growing season precipitation comparable to the annual precipitation estimate from leaf area analysis. These data are interpreted as reflecting high summer precipitation in the Arctic during the late Paleocene to middle Eocene, including ETM1, as precipitation in the dark polar winter months will have had no effect on leaf size while the trees were dormant, corroborating the results from Eocene wood chemistry. High summer precipitation (i.e., light-season = wettest season) in the Eocene Arctic during hyperthermals would have contributed to regional warmth.
Effects of foliage clumping on the estimation of global terrestrial gross primary productivity
NASA Astrophysics Data System (ADS)
Chen, Jing M.; Mo, Gang; Pisek, Jan; Liu, Jane; Deng, Feng; Ishizawa, Misa; Chan, Douglas
2012-03-01
Sunlit and shaded leaf separation proposed by Norman (1982) is an effective way to upscale from leaf to canopy in modeling vegetation photosynthesis. The Boreal Ecosystem Productivity Simulator (BEPS) makes use of this methodology, and has been shown to be reliable in modeling the gross primary productivity (GPP) derived from CO2flux and tree ring measurements. In this study, we use BEPS to investigate the effect of canopy architecture on the global distribution of GPP. For this purpose, we use not only leaf area index (LAI) but also the first ever global map of the foliage clumping index derived from the multiangle satellite sensor POLDER at 6 km resolution. The clumping index, which characterizes the degree of the deviation of 3-dimensional leaf spatial distributions from the random case, is used to separate sunlit and shaded LAI values for a given LAI. Our model results show that global GPP in 2003 was 132 ± 22 Pg C. Relative to this baseline case, our results also show: (1) global GPP is overestimated by 12% when accurate LAI is available but clumping is ignored, and (2) global GPP is underestimated by 9% when the effective LAI is available and clumping is ignored. The clumping effects in both cases are statistically significant (p < 0.001). The effective LAI is often derived from remote sensing by inverting the measured canopy gap fraction to LAI without considering the clumping. Global GPP would therefore be generally underestimated when remotely sensed LAI (actually effective LAI by our definition) is used. This is due to the underestimation of the shaded LAI and therefore the contribution of shaded leaves to GPP. We found that shaded leaves contribute 50%, 38%, 37%, 39%, 26%, 29% and 21% to the total GPP for broadleaf evergreen forest, broadleaf deciduous forest, evergreen conifer forest, deciduous conifer forest, shrub, C4 vegetation, and other vegetation, respectively. The global average of this ratio is 35%.
21 CFR 520.1195 - Ivermectin liquid.
Code of Federal Regulations, 2014 CFR
2014-04-01
... micrograms (mcg) per kilogram (/kg) of body weight as a single dose by stomach tube or as an oral drench. (ii...): Trichostrongylus axei; Large mouth Stomach Worms (adults): Habronema muscae; Bots (oral and gastric stages... larvae)); Hairworms (Trichostongylus axei(adult)); Large mouth Stomach Worms (Habronema muscae (adult...
21 CFR 520.1195 - Ivermectin liquid.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) Amount. 200 micrograms (mcg) per kilogram (/kg) of body weight as a single dose by stomach tube or as an...): Trichostrongylus axei; Large mouth Stomach Worms (adults): Habronema muscae; Bots (oral and gastric stages... larvae)); Hairworms (Trichostongylus axei(adult)); Large mouth Stomach Worms (Habronema muscae (adult...
21 CFR 520.1195 - Ivermectin liquid.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) Amount. 200 micrograms (mcg) per kilogram (/kg) of body weight as a single dose by stomach tube or as an...): Trichostrongylus axei; Large mouth Stomach Worms (adults): Habronema muscae; Bots (oral and gastric stages... larvae)); Hairworms (Trichostongylus axei(adult)); Large mouth Stomach Worms (Habronema muscae (adult...
Enterobius vermicularis in the male urinary tract: a case report
Zahariou, Athanasios; Karamouti, Maria; Papaioannou, Polyanthi
2007-01-01
Enterobius vermicularis is an intestinal nematode of humans. Adults usually have low worm burdens and are asymptomatic. Ectopic infections in the pelvic area or urinary tract rarely occur in women. We report a case of the patient with mild voiding difficulties such as urgency, frequency, nocturia, dysuria, mild low back pain or perineal discomfort. The patient's prostatic secretions showed a large number of inflammatory cells and several eggs. The size and the shape of the eggs identified them as a group of E. vermicularis. On examination we found a soft palpable material which was 5 mm diameter in size and spherical shape. Palpation gave the impression of a tissue than a stone. An incision was performed and a 4 mm long living worm was found. The microscopic examination identified the worm as E- vermicularis. It is an extremely rare manifestation of enterobius vermicularis infection since an intestinal-breeding worm is rarely found in the male genital tract. PMID:18001478
Sakamoto, Mitsuo; Sato, Fumiya; Mizuno, Yasutaka; Komatsuzaki, Makoto; Yoshikawa, Koji; Yoshida, Masaki; Shiba, Kohya; Onodera, Shoichi; Hosoya, Tatsuo; Kumagai, Masahiro
2004-05-01
We report a patient with gnathostomiasis in whom a specific diagnosis of Gnathostoma spinigerum infestation was made morphologically upon removal of the worm. A 47-Year-old Japanese male on a business trip to Vietnam ate fried frog with a Vietnamese friend in January 2002, the friend was diagnosed with gnathostomiasis in June 2002. The patient noted swelling of the right leg with migration to the right arm, prompting him to our hospital in February 2003. Hematologic examination showed eosinophilia, and specific anti-gnathostome antibody was detected by a dot enzyme-linked immunosorbent assay (Dot ELISA) in the serum. He was diagnosed as gnathostomiasis, and was given albendazole 400 mg b.i.d. On day 11 of therapy the patient removed a larval worm from the right palmar lesion by pinching with his nails. The worm was identified as G. spinigerum based on morphologic characteristics including number of hooklets on its head-bulb. When gnathostomiasis is suspected, albendazole should be administered before incision of the skin lesion.
The growth and development of Schistosoma mansoni in mice exposed to sublethal doses of radiation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aitken, R.; Wilson, R.A.
1989-12-01
The maturation of Schistosoma mansoni was studied in mice exposed to various sublethal doses of radiation. Although the treatment of mice with 500 rads of radiation prior to infection did not alter parasite maturation, doses in excess of 500 rads led to a reduction in worm burden. This could not be attributed to a delay in the arrival of parasites in the hepatic portal system. Worms developing in mice treated with 800 rads commenced egg-laying about 1 wk later than worms in intact mice, and the rate of egg deposition appeared to be lower in irradiated hosts. The data demonstratemore » that exposure of C57BL/6 mice to doses of radiation in excess of 500 rads impairs their ability to carry infections of S. mansoni. The findings do not support the hypothesis that primary worm burdens in the mouse are controlled by a host immune response.« less
Yamaguchi, Nobuo; Yoshinaga, Masafumi; Kamino, Kei; Ueki, Tatsuya
2016-06-01
Polychaete fan worms and ascidians accumulate high levels of vanadium ions. Several vanadiumbinding proteins, known as vanabins, have been found in ascidians. However, no vanadium-binding factors have been isolated from the fan worm. In the present study, we sought to identify vanadiumbinding proteins in the branchial crown of the fan worm using immobilized metal ion affinity chromatography. A nucleoside diphosphate kinase (NDK) homolog was isolated and determined to be a vanadium-binding protein. Kinase activity of the NDK homologue, PoNDK, was suppressed by the addition of V(IV), but was unaffected by V(V). The effect of V(IV) on PoNDK precedes its activation by Mg(II). This is the first report to describe the relationship between NDK and V(IV). PoNDK is located in the epidermis of the branchial crown, and its distribution is very similar to that of vanadium. These results suggest that PoNDK is associated with vanadium accumulation and metabolism in P. occelata.
Worms under Pressure: Bulk Mechanical Properties of C. elegans Are Independent of the Cuticle
Gilpin, William; Uppaluri, Sravanti; Brangwynne, Clifford P.
2015-01-01
The mechanical properties of cells and tissues play a well-known role in physiology and disease. The model organism Caenorhabditis elegans exhibits mechanical properties that are still poorly understood, but are thought to be dominated by its collagen-rich outer cuticle. To our knowledge, we use a novel microfluidic technique to reveal that the worm responds linearly to low applied hydrostatic stress, exhibiting a volumetric compression with a bulk modulus, κ = 140 ± 20 kPa; applying negative pressures leads to volumetric expansion of the worm, with a similar bulk modulus. Surprisingly, however, we find that a variety of collagen mutants and pharmacological perturbations targeting the cuticle do not impact the bulk modulus. Moreover, the worm exhibits dramatic stiffening at higher stresses—behavior that is also independent of the cuticle. The stress-strain curves for all conditions can be scaled onto a master equation, suggesting that C. elegans exhibits a universal elastic response dominated by the mechanics of pressurized internal organs. PMID:25902429