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Striated craniofacial and limb muscles differ in their embryological origin, regulatory program during myogenesis, and innervation. In an attempt to explore the effects of these differences on the striated muscle phenotype in humans, the expression of myosin and myosin-associated thick filament proteins were studied at the single fiber level both in the human jaw-closing masseter muscle and in two limb muscles (biceps brachii and quadriceps femoris muscles). In the masseter, unique combinations of myosin heavy chain (MyHC) and myosin binding protein C (MyBP-C) isoforms were observed at the single fiber level. Compared to the limb muscles, the MyHC isoform expression was more complex in the masseter while the opposite was observed for MyBP-C. In limb muscles, a coordinated expression of three MyHC and three MyBP-C isoforms were observed, i.e., single fibers contained one or two MyHC isoforms, and up to three MyBP-C isoforms. Also, the relative content of the different MyBP-C isoforms correlated with the MyHC isoform expression. In the masseter, on the other hand, up to five different MyHC isoforms could be observed in the same fiber, but only one MyBP-C isoform was identified irrespective MyHC isoform expression. This MyBP-C isoform had a migration rate similar to the slow MyBP-C isoform in limb muscle fibers. In conclusion, a unique myofibrillar protein isoform expression was observed in the human masseter muscle fibers, suggesting significant differences in structural and functional properties between muscle fibers from human masseter and limb muscles. [ABSTRACT FROM AUTHOR]

TONGUE, MORPHOLOGY, COMPARATIVE anatomy, MUSCLES, and MOUTH

The muscle fibre composition of three human intrinsic tongue muscles, the longitudinalis, verticalis and transversus, was investigated in four anterior to posterior regions of the tongue using morphological and enzyme- and immunohistochemical techniques. All three muscles typically contained type I, IIA and IM/IIC fibres. Type I fibres expressed slow myosin heavy chain (MyHC), type II fibres fast MyHC, mainly fast A MyHC, whereas type IM/IIC coexpressed slow and fast MyHCs. Type II fibres were in the majority (60%), but regional differences in proportion and diameter of fibre types were obvious. The anterior region of the tongue contained a predominance of relatively small type II fibres (71%), in contrast to the posterior region which instead showed a majority of larger type I and type IM/IIC fibres (66%). In general, the fibre diameter was larger in the posterior region. This muscle fibre composition of the tongue differs from those of limb, orofacial and masticatory muscles, probably reflecting genotypic as well as phenotypic functional specialization in oral function. The predominance of type II fibres and the regional differences in fibre composition, together with intricate muscle structure, suggest generally fast and flexible actions in positioning and shaping the tongue, during vital tasks such as mastication, swallowing, respiration and speech.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

PLANT chemical defenses, VIGNA, and COREIDAE

The effects of secondary metabolites in different Vigna species on the development of Clavigralla tomentosicollis were investigated in an artificial seed system using different fractions of crude pod extracts, while the orientation response of this pod-bug to volatile extracts was studied using a dual-choice olfactometer. Feeding on the neutral fraction extracts, in contrast to the basic and acidic fractions, resulted in significantly higher mortalities, longer total developmental time, and lower growth index of the insects in comparison with controls. All volatile extracts elicited an avoidance reaction by C. tomentosicollis, except the volatile from the susceptible genotype IT84S-2246 which generally attracted as many insects as controls. Extracts from wild Vigna species showed higher activity than those from their cultivated relatives. The present study which has established that most secondary metabolites in cowpea pods were localized in the neutral fraction of the crude extract, could facilitate experiments on the separation and characterization of the toxic factors involved. [ABSTRACT FROM AUTHOR]

ELECTRICAL steel, ELECTRICAL engineering materials, SILICON steel, STEEL, IRON, and STEEL alloys

The results of investigation of the relation between the grain size in the intermediate stages of manufacturing electrical steel and various physical characteristics are given. The investigations are carried out for the purpose of clarifying the possibility of using these characteristics for arranging nondestructive testing of the grain size in the process of steel manufacturing. The paper contains the results of tests performed with the use of the methods of measuring the leakage magnetic fields on the grain boundaries by means of yttrium iron garnet films employed for visualization of the magnetic fields, the Barkhausen effect, the ultrasonic and eddy-current methods, the electromagnetic-acoustic conversion (EMAC) method, and the use of the relation between the grain size and the value of the coercive force. [ABSTRACT FROM AUTHOR]

COWPEA, LEGUMES, DEFOLIATION, PLANT canopies, SEED disinfection, EFFECT of temperature on plants, and PHYSIOLOGICAL effects of temperature

Pottedcowpea, Vigna unguiculata (L.) Walp., plants were used to determine the effects of defoliation and pod position relative to the leaf canopy on infestation and damage by the coreid pod-bugs Clavigralla tomentosicollis Stål and Anoplocnemis curvipes (F.). Temperature measurements were taken within and outside the canopy to determine whether there was a correlation to seed damage. Seed damage decreased significantly with increasing defoliation in plants infested with C. tomentosicollis; an inverse trend was observed with A. curvipes. Temperatures within the canopy increased as the number of leaves decreased. As observed in the defoliation experiment, C. tomentosicollis and A. curvipes reacted differently in a free-choice situation between pods located outside or within the canopy. Significantly higher numbers of C. tomentosicollis concealed themselves within the canopy, where they caused more severe damage to seeds, in comparison with numbers and damage outside the canopy. These trends were reversed for A. curvipes. There was a significant negative correlation between percentage of seed damage and temperature with C. tomentosicollis, and a significant positive correlation with A. curvipes, both in defoliated plants and those with pods distributed outside and within the canopy. Overall, plants with less dense canopy, and long peduncles holding pods outside the canopy showed some resistance to C. tomentosicollis, which is the most damaging pod bug on cowpea. Because such cowpea plants harbor fewer C. tomentosicollis, they are likely to suffer less overall damage from infestation by the complex of pod bugs that occur concurrently in cowpea fields. [ABSTRACT FROM AUTHOR]

HEMIPTERA, COTTON diseases & pests, and STEREOCHEMISTRY

Research was conducted to evaluate the possibility that a plant bug damaging cotton, Gossypium hirsutum L., in south Texas is actually green mind, Creontiades dillutus Stål, which is the primary plant bug pest of cotton in Australia. Molecular comparisons targeting a fragment of the COl region of mitochondrial DNA were made on Creontiades specimens collected from the Lower Rio Grande Valley of Texas and specimens of green mind and brown mind, C. pacificus Stål, collected from Queensland, Australia. The emerging south Texas cotton pest is neither of the species tested from Australia; rather it is a closely related, possibly indigenous species. Further morphological systematics work is needed to identify the Creontiades species from Texas, and collection of additional specimens from several locations where it is known to occur is ongoing. [ABSTRACT FROM AUTHOR]

ETHYLENE glycol, THERMODYNAMICS, HYDROGEN bonding, SUPRAMOLECULAR chemistry, SOLVENTS, and CHEMICAL reduction

Substitution of hydrogen bond directed supramolecular assemblies with ethylene glycol chains leads to a reduction in the association constant in apolar solvents, where the reduction of the association constant is dependent on the length of the aliphatic spacer connecting the hydrogen bonds and the ethylene glycol chain. [ABSTRACT FROM AUTHOR]

COMPARTMENT syndrome, THERAPEUTICS, ANALYSIS of variance, CAPILLARIES, CHI-squared test, COMPUTER software, EXERCISE, IMMUNOHISTOCHEMISTRY, LEG, LONGITUDINAL method, MICROCIRCULATION, MUSCLES, RESEARCH funding, STRIATED muscle, T-test (Statistics), DATA analysis, CASE-control method, ANALYTICAL chemistry, PATHOLOGY, DONOR blood supply, and FASCIAE surgery

There is a paucity of data regarding the pathogenesis of chronic exertional compartment syndrome (CECS), its consequences for the muscles and the effects of treatment with fasciotomy. We analyzed biopsies from the tibialis anterior muscle, from nine patients, obtained during a decompressing fasciotomy and during follow-up 1 year later. Control biopsies were obtained from nine normal subjects. Muscle capillarity, fiber-type composition and fiber area were analyzed with enzyme- and immunohistochemistry and morphometry. At baseline, CECS patients had lower capillary density (273 vs 378 capillaries/mm, P=0.008), lower number of capillaries around muscle fibers (4.5 vs 5.7, P=0.004) and lower number of capillaries in relation to the muscle fiber area (1.1 vs 1.5, P=0.01) compared with normal controls. The fiber-type composition and fiber area did not differ, but focal signs of neuromuscular damage were observed in the CECS samples. At 1-year follow-up after fasciotomy, the fiber area and the number of fibers containing developmental myosin heavy chains were increased, but no enhancement of the capillary network was detected. Thus, morphologically, patients with CECS seemed to have reduced microcirculation capacity. Fasciotomy appeared to trigger a regenerative response in the muscle, however, without any increase in the capillary bed. [ABSTRACT FROM AUTHOR]

RHODNIUS, CONENOSES, CLASSIFICATION of insects, and SPECIES diversity

Tribe Rhodniini includes Rhodnius Stål and Psammolestes Bergroth. Enzymatic and molecular evidence suggest the tribe is monophyletic. Most species are wild, living in palms and bird nests. Traditionally both genera were considered related; nevertheless, molecular studies don't support the Rhodnius monophyly. The goal was to phylogenetically analyze morphometric variation in wing architecture in support of Rhodniini taxonomy and systematics. We photographed 524 wings of five representatives of Rhodniini: Psammolestes arthuri (Pinto) (n = 89), Rhodnius pictipes Stål (n = 21), R. robustus Larrousse (n = 24), R. prolixus Stål (n = 16), and R. neivai Lent (n = 22). As outgroups we studied four representatives of Triatomini: Eratyrus mucronatus Stål (n = 15), Panstrongylus rufotuberculatus (Champion) (n = 45), P. geniculatus (Latreille) (n = 183), and Triatoma maculata (Erichson) (n = 109). Landmark coordinate (x, y) configurations were registered and aligned by Generalized Procrustes Analysis. Covariance Analyses were implemented with proportions of re-classified groups and MANOVA. Then, wing shape variables (confidence intervals from relative warps) and centroid size were cladistically analysed. Statistical analyses of variance found not significant differences in wing isometric size (Kruskal-Wallis) among P. arthuri-R. neivai-R. pictipes; R. robustus-R. prolixus-T. maculata and between P. rufotuberculatus-P. geniculatus. The a posteriori re-classification was perfect in E. mucrunatus 100% and R. pictipes, followed by T. maculata 96%, R. neivai 95%, P arthuri 93.2%; R. prolixus 87.5%, P. geniculatus 87.4%, P. rufotuberculatus 84.4%, and R. robustus 76%. Cladistic analyses under parsimony selected two most parsimonious trees (L=4.461 IC=0.973 and IR=0.979), where the strict consensus showed a monophyletic group with Panstrongylus (rufotuberculatus + geniculatus) and Triatoma + Rhodniini (Rhodinus + Psammolestes), but internally it shows the paraphyly of Rhodnius regarding Psammolestes. The congruence between these results and previous molecular analyses in Rhodniini, reveal the phylogenetic information of our morphometric characters as support to systematic studies, allowing the combination of geometric morphometrics and phylogenetic methods for the first time in this group. [ABSTRACT FROM AUTHOR]

EXITIANUS, CORN diseases, LEAFHOPPERS, and INSECTS

"Corn stunt" caused by the mollicute Spiroplasma kunkelii (Whitcomb) is potentially one of the most severe diseases affecting the corn (Zea mays L.) crop in the Americas, and the leafhopper Dalbulus maidis (DeLong & Wolcott) is considered its most important vector. However, other insects seen quite frequently in corn crops might well be its vectors in Argentina. To identify any leafhoppers species other than D. maidis that can transmit S. kunkelii, transmission assays were conducted, using individuals of Exitianus obscurinervis (Stål) collected in field and reared under controlled conditions. S. kunkelii was transmitted to corn plants by E. obscurirwrvis. The pathogen was transmitted to seven of the 11 plants, which showed characteristic corn stunt symptoms, and the presence of the pathogen was confirmed by DAS-ELISA. The presence of S. kunkelii in the E. obscurinervis individuals used in transmission experiments was confirmed by polymerase chain reaction and electron microscopy. The current study shows the existence of a new experimental vector of S. kunkelii, the leafhopper E. obscurinervis, which acquired spiroplasmas from infected plants and inoculated it to healthy plants. [ABSTRACT FROM AUTHOR]

ESSENTIAL oils, REPELLENTS, STINKBUGS, HEMIPTERA, LEMONGRASS oil, SPEARMINT oil, and METHYL benzoate

The brown marmorated stink bug ( BMSB), Halyomorpha halys ( Stål), native to Northeastern Asia, is a serious invasive pest in the United States, Canada, Switzerland, Germany and France. Several common essential oils and their compositions were tested against BMSBs as potential repellents. All the tested individual essential oils and a ternary oil blend showed significant repellency to both BMSB nymphs and adults. Clove oil, lemongrass oil, spearmint oil, ylang-ylang oil, and the ternary oil mixture (clove, lemongrass and spearmint) almost completely blocked attraction of BMSBs to the stink bug attractant-baited traps; whereas wintergreen oil, geranium oil, pennyroyal oil and rosemary oil resulted in 60-85% trap catch reductions. Over 20 BMSB antennally active compounds were identified from SPME headspace samples of the eight repellent essential oils using GC- EAD and GC- MS techniques. Among the synthetic EAD-active compounds tested in the field, eugenol, l-carvone, p/l-menthone, pulegone, methyl salicylate, trans/ cis-citral, methyl benzoate and β-caryophyllene significantly reduced trap catches of BMSBs by 72-99%; these compounds are likely responsible for the repellency of their corresponding essential oils. Surprisingly, a synthetic mixture of the predacious spined soldier bug ( SSB) [ Podisus maculiventris (Say)] aggregation pheromone ( trans-2-hexenal, α-terpineol and benzyl alcohol) also showed a significant inhibition of BMSB response to its attractants. These repellent essential oils and their active compounds, as well as the synthetic SSB pheromone, are potentially useful as part of an efficient, environmentally sound semiochemical-based IPM programme to combat this serious invasive stink bug. [ABSTRACT FROM AUTHOR]

ORGANOCATALYSIS, AMPHIPHILES, NAPHTHALIMIDES, STEREOSELECTIVE reactions, ALDOL condensation, and CYCLOHEXANONES

Here, a modular approach is reported to introduce a specific function into single-chain polymeric nanoparticles (SCPNs). Hereto, an amphiphilic polymer with pendant benzene-1,3,5-tricarboxamide (BTA) units is mixed with a 'free' BTA that contains a functional group, either a fluorescent naphthalimide or a catalytically active l-proline. Taking advantage of hydrophobic interactions and self-recognition properties of the BTA units, the 'free' BTAs are captured into the interior of the SCPN in water as evidenced by fluorescence studies. To illustrate that function can be readily introduced using a modular approach, l-proline-based BTAs are incorporated to procure a catalytically active SCPN in water. The aldol reaction between p-nitrobenzaldehyde and cyclohexanone shows good conversions at low catalyst loadings and substrate concentrations, and high stereoselectivities are obtained ( de = 91% and ee = 98%). [ABSTRACT FROM AUTHOR]

BIOLOGICAL control of plant parasites, LEPIDOPTERA, ENTOMOPHAGOUS insects, PREDATORY insects, and HORTICULTURE

Pest suppression through biological control seeks to maximize the action of the pest's natural enemies with the goal of reducing pesticide use. We present a summary of published studies and original findings on several entomophagous species as biocontrol agents of Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), a key pest of tomato crops in Argentina, with the aim to select potential candidates for its management. Spontaneously occurring T. absoluta egg parasitism was lower than that inflicted by the larval parasitoids Dineulophus phthorimaeae (De Santis, 1983) (Hymenoptera: Eulophidae) and Pseudapanteles dignus (Muesebeck, 1938) (Hymenoptera: Braconidae). These parasitoids exhibit important life history traits in laboratory conditions and produce relevant amounts of T. absoluta mortality in the field. Surveys carried out in Tucumán and Buenos Aires provinces, Argentina, revealed that D. phthorimaeae and P. dignus coexist in tomato and eggplant crops; T. absoluta- P. dignus interaction is also found on other non-cultivated solanaceous species present in horticultural farms. In addition, studies are currently under way to determine the predation ability of Zelus obscuridorsis (Stål, 1860) (Hemiptera: Reduviidae) on both larvae and adults of the pest. Finally, we discuss the prospects for implementing experimental augmentative releases of P. dignus to control the pest, a candidate selected considering various positive biological traits and because of its simple mass production and manipulation compared with other antagonists of T. absoluta. [ABSTRACT FROM AUTHOR]

STIMULANTS, LEAFHOPPERS, RICE diseases & pests, BIOLOGICAL assay, and METHANOL

A crude rice extract caused a higher probing response than did the control in the green rice leafhopper, Nephotettix nigropictus. Bioassay-guided separation led to the isolation of four active compounds, isoscoparin 2"-O-glucoside, isoscoparin 2"-O-(6"'-(E)-feruloyl)glucoside, isoscoparin 2"-O-(6"'-(E)-p-coumaroyl)glucoside, and isovitexin 2"-O-(6"'- (E)-feruloyl)glucoside from ODS 40% methanol in water faction. Each of the compounds, or any combination without one of the four compounds, caused weaker probing responses than the crude rice extract. The activity was recovered only when all the compounds were combined. [ABSTRACT FROM AUTHOR]

SOYBEAN diseases & pests, BROWN marmorated stink bug, and STINKBUGS

Sampling soybean fields for the brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), can be challenging. Both adults and nymphs have a "startle response" and drop to the ground with even the slightest disturbance. This behavior could reduce the effectiveness of the traditional sweep net and ground cloth sampling methods. In 2013 and 2014, in Virginia, Delaware, and Maryland, we evaluated a visual plant inspection method that consisted of counting the number of brown marmorated stink bug nymphs and adults seen on soybean plants in a 2-min inspection period while walking carefully between two rows. After a 30-min interval, which allowed the stink bugs to reposition in the canopy, the area was resampled using 15 sweeps with a 38-cm-diameter sweep net. In total, 76 soybean fields and 2,042 paired comparisons were used to determine a strong linear relationship between sampling methods (y = 0.984x + 0.4359, R2 = 0.6934, where y = brown marmorated stink bugs/2-min visual count and x = brown marmorated stink bugs/15 sweeps). An average visual count of 5.4 brown marmorated stink bugs in 2 min was estimated as being equivalent to the current economic threshold of 5 stink bugs per 15 sweeps. Visual inspection appears to be an effective method for assessing brown marmorated stink bug populations in soybeans. [ABSTRACT FROM AUTHOR]

RICE diseases & pests, NILAPARVATA lugens, LOCUS (Genetics), GENETIC markers in plants, and RICE breeding

Brown planthopper ( BPH), Nilaparvata lugens Stål ( Hemiptera: Delphacide), is a destructive insect pest of rice, Oryza sativa L. ( Poaceae), in rice-producing areas worldwide. Host plant resistance is a major aspect of managing this pest. In this study, a mapping population consisting of 150 F3 lines, derived from a cross of MR276 and Rathu Heenati, was used to detect and analyse quantitative trait loci ( QTLs) for the resistance to BPH. Composite Interval Mapping ( CIM) was used for QTL detection. In total 10 QTLs controlling BPH resistance were mapped on chromosomes 1, 3, 6, 7, 9, 10, and 12. Four QTLs - qBph-1-1, qBph-3-1, qBph-6-1, and qBph-7-1 - were mapped on chromosomes 1, 3, 6, and 7 in the standard seedbox screening test, explaining 41% of the phenotypic variance. Two QTLs, qBph-6-1 and qBph-9-1, were detected on chromosomes 6 and 9 in the honeydew test, accounting for 32% of the total phenotypic variance. Moreover, four QTLs - qBph-3-1, qBph-6-1, qBph-10-1, and qBph-12-1 - were identified on chromosomes 3, 6, 10, and 12 expressing antixenosis to BPH and explaining 41% of the phenotypic variance. QTL qBph-3-1 was located in the chromosomal region between markers RM231 and RM3872 on chromosome 3, and QTL qBph-6-1 was located in the region between RM588 and RM204 on chromosome 6, indicating that these regions have a major effect in controlling the resistance to BPH in the population studied. The molecular markers linked to QTLs that are identified will be useful in the development of varieties resistant to BPH. Our study contributes to the development of genetic material for breeding programmes and marker-assisted selection ( MAS) in rice to improve BPH resistance. [ABSTRACT FROM AUTHOR]