bluuebunny/crossref_metadata_2025 huggingface dataset:
Description of a New Spotted-Thorax Drosophila (Diptera: Drosophilidae) Species and its Evolutionary Relationships Inferred by a Cladistic Analysis of Morphological Traits
Authors: Acurio Andrea , Rafael Violeta , Céspedes Diego , Ruiz Alfredo
Published: November 2013

A phylogenetic approach based on morphological characters is the only alternative applicable in cases where molecular data are unavailable. During a taxonomic inventory of Drosophilidae in 12 localities of Ecuador (South America), we discovered a new species of cactophilic spotted-thorax Drosophila Fallen that here we formally describe as Drosophila machalilla Acurio 2013. To classify this new species, we analyzed the terminalia of male and female adults, finding similarities with flies of two neotropical spotted-thorax species groups of Drosophila, namely rep leta and peruensis. Flies or DNA sequence data are unavailable for the latter species group, hindering a molecular approach. Thus, to accurately classify the new species, we carried out a maximum parsimony cladistic analysis using 52 morphological characters from nine representative taxa of virilis, willistoni, repleta, and peruensis species groups. The results indicate that D. machalilla sp. nov. belongs neither to the repleta group nor to the peruensis group and suggest that a new species group should be erected to house D. machalilla and Drosophila atalaia Vilela & Sene (1982, previously considered a member of the peruensis species group).
Morphology of Mature Larvae of Three Species of the Genus Anthrenus (Dermestidae: Megatominae: Anthrenini) with Comparisons to Related Species
Authors: Kadej Marcin , Jaroszewicz Sylwia , Tarnawski Dariusz
Published: November 2013

Description of the last larval instar (based on larvae or exuviae) of Anthrenus (Helocerus) minutus (Erichson, 1848), Anthrenus (Nathrenus) biskrensis (Reitter, 1886), and Anthrenus (Nathrenus) signatus (Erichson, 1848; Coleoptera: Dermestidae) is presented. Morphological characters of Anthrenus larvae such as general morphology of antenna, epipharynx, mandible, maxilla, ligula with labial palpi, hastisetae, legs, and terga, and condition of antecostal suture, are documented and discussed. Structural differences among mature larvae of the following Anthrenus species are compared and summarized: Anthrenus coloratus (Reitter, 1881), Anthrenus delicatus delicatus (Kiesenwetter, 1851), Anthrenus flavipes flavipes (LeConte, 1854), Anthrenus fuscus (Olivier, 1789), Anthrenus museorum (L., 1761), Anthrenus latefasciatus (Reitter, 1892), Anthrenus oceanicus (Fauvel, 1903), Anthrenus olgae (Kalík, 1946), Anthrenus picturatus makolskii (Mroczkowski, 1950), Anthrenus pimpinellae pimpinellae (F., 1775), Anthrenus sarnicus (Mroczkowski, 1963), Anthrenus scrophulariae scrophulariae (L., 1758), Anthrenus sophonisba (Beal, 1998), and Anthrenus verbasci (L., 1767).
Description of a New Species of Diastrophus (Hymenoptera: Cynipidae: “Aylacini”) from Colombia: The First Herb Gall Wasp Native to the Neotropical Region
Authors: Nieves-Aldrey José Luis , Rodríguez Pedro A , Medianero Enrique
Published: November 2013

We describe Diastrophus colombianus Nieves-Aldrey sp. nov., a gall inducer on Rubus glaucus Bentham (Rosaceae) in Colombia. This is the first reliable record of a species of Diastrophus Hartig, 1840 (Hymenoptera: Cynipidae) and of an herb gall wasp (Cynipidae: “Aylacini”) native to the Neotropical region. The phylogenetic relationships among the members of Diastrophus—D. colombianus and the species considered by a previous study—were inferred from adult morphological and gall characteristics. Our results suggest that D. colombianus is more closely related to a clade composed of Diastrophus austrior Kinsey, Diastrophus rubi (Bouché), Diastrophus fragariae Beutenmüller, and Diastrophus tumefactus Kinsey.
The Effect of Prior Chilling Exposure on Supercooling Ability and Developmental Success in Third-Instars of Eurosta solidaginis(Diptera: Tephritidae)
Authors: Robich Sarah R , Layne Jack R
Published: November 2013

The ability to initiate freezing at elevated subzero temperatures is deemed an important adaptation in freeze-tolerant insects, as this phenotype allows them to avoid potentially lethal flash freezing and to conserve both body water and stored energy. We investigated the effects of recent freeze exposure on the subsequent supercooling points (SCPs) of overwintering freeze-tolerant larvae (third instars) of the dipteran Eurosta solidaginis Fitch. This large data set also allowed us to characterize the distribution profile for SCPs and the potential impact of body size on this parameter. Larvae having recent freeze exposure maintained their seasonally elevated SCPs, with one group, 2 d postfreeze, showing a significant (P < 0.05) rise in their SCPs. Larvae that experienced supercooling to -7°C did not show a significant (P> 0.05) rise in their SCPs. Despite differences in total body water content among larvae of varying body sizes, there was not a significant (P>0.05) relationship between body mass and the initial SCP values, but there was an absence of normality (negative skewing) in the SCP values. Larvae completing their life cycles had SCPs equivalent to values for larvae that failed to complete the life cycle. Our findings demonstrate actions of potent ice nucleators such that the response is maintained and possibly enhanced following a recent freeze event. Ice nucleation in Eurosta larvae negates the impact of variation in water content, but individual variation in SCP does not have a survival consequence when gauged under laboratory conditions.
Biology and Fertility Life Table ofAganaspis pelleranoi(Hymenoptera: Figitidae) in Larvae ofAnastrepha fraterculusandCeratitis capitata(Diptera: Tephritidae)
Authors: Gonçalves R S , Nava D E , Pereira H C , Lisbôa H , Grützmacher A D , Valgas R A
Published: November 2013

Aganaspis pelleranoi (Brèthes) (Hymenoptera: Figitidae) is an important fruit fly parasitoid native to the Neotropics. We investigated the biology and constructed a fertility life table for A. pelleranoi reared on larvae of Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Parasitoid development was investigated in larvae of the two fruit fly species by recording the duration of the egg-adult period, number of offspring, sex ratio, adult weight, adult hind tibia length, and male and female longevity, and constructing a fertility life table. Parasitoids reared on An. fraterculus larvae produced more offspring, had shorter egg-adult periods, greater proportion of females and longer survival, and higher percent emergence than parasitoids reared on C. capitata larvae. Moreover, A. pelleranoi individuals reared on An. fraterculus larvae were heavier and had longer hind tibia than those reared on C. capitata. Based on life table statistics, the time required to double the population (Td) was ≈3.4 times shorter for parasitoids reared on An. fraterculus larvae. Our results show that A. pelleranoi develops better on larvae from An. fraterculus than C. capitata, indicating that this species could be used for the mass production of this parasitoid intended for augmentative biological control of fruit flies.
Differential Effects of 4-n-Nonylphenol on Glutathione, Glutathione S-Transferase, and Glutathione Peroxidase on Gonads in Different Developmental Stages in the Bombyx mori (Lepidoptera: Bombycidae)
Authors: Yuan Hong-Xia , Sima Yang-Hu , Xu Shi-Qing
Published: November 2013

Bombyx mori L. larvae were exposed to 4-n-nonylphenol (4-NP) in the laboratory, and their glutathione S-transferase, glutathione peroxidase, and corresponding mRNA levels in gonads during different developmental stages (larval, pupal, and adult) were evaluated. Developmental parameters and glutathione content were also measured. Altered patterns of pupation and adult emergence were observed after exposure to 0.05–0.4 g/kg 4-NP during the entire larval stage. When exposed to 0.4 g/kg 4-NP, the sex ratio (male/female) of the emerged adults increased rapidly from 0.91 ±0.09 to 1.96 ±0.26. A decrease in glutathione content was observed at the larval, pupal, and adult stages. In addition, at 0.05 g/kg 4-NP and higher concentrations, an increase in glutathione S-transferase, glutathione peroxidase activity, and the gene expression level of glutathione S-transferase d1 and glutathione peroxidase were detected in the larval stage, followed by a decline in glutathione S-transferase d1 and glutathione peroxidase transcript levels along with enzyme activity in the pupal and adult stages. The changing trend in mRNA levels of these enzymes was consistent with that of enzyme activity. The results suggest a relationship between 4-NP and alterations in the levels of glutathione-related detoxification enzymes in B. mori gonads.
Distribution and Differentiation ofHenosepilachna diekei(Coleoptera: Coccinellidae) on Two Host-Plant Species Across Java, Indonesia
Authors: Fujiyama Naoyuki , Ueno Hideki , Kahono Sih , Hartini Sri , Matsubayashi Kei W , Kobayashi Norio , Katakura Haruo
Published: November 2013

Divergent natural selection on different host plants may be a crucial factor in promoting the remarkable diversity of phytophagous insects, and might occur in any geographical context. Because the intensity and consequences of divergent selection on different hosts can vary depending on the degree of gene flow between conspecific insect populations, elucidating the geographical context and degree of host specificity in the incipient phase of differential host use is indispensable to understanding the diversification process in phytophagous insects. Henosepilachna diekei Jadwiszczak & Węgrzynowicz (Coleoptera: Coccinellidae) is a tropical ladybird beetle occurring mainly on two host species from different plant families, Asteraceae and Lamiaceae. We investigated the geographical distribution of H. diekei across Java, Indonesia, in relation to the availability of the two hosts, and examined the host specificity of beetles in the laboratory. We also investigated genetic relationships among local populations of beetles using mitochondrial NADH dehydrogenase subunit 2 gene sequences. Geographic variation in host use by H. diekei was largely determined by skewed geographical distributions of the hosts, although there was a synergistic effect with extremely divergent host specificity by the beetles. The molecular analyses suggested that genetic differentiation among the beetle populations has occurred and has been maintained by the effects of both geographical distance and divergent host specificity. The geographical distribution of H. diekei populations differing in host specificity suggests that geographical distance, local host-plant availability, and divergent host specificity contribute synergistically to promote the genetic differentiation and subsequent diversification of phytophagous insects on different hosts.
Adult Growth in Opilioacaridae with 1904 (Acari: Parasitiformes: Opilioacarida)
Authors: Bernardi Leopoldo Ferreira De Oliveira , Klompen Hans , Ferreira Rodrigo Lopes
Published: November 2013

Mites in the order Opilioacarida are known to undergo postimaginal molting. The process has been associated with the ability to regain lost appendages, but may also result in growth and increases in numbers of specific setae. These processes were observed in four individuals, with two of these showing increases in setal lengths ranging from 8.1 to 16.6%. Qualitative growth, in the form of an increase from 5 to 6 in the number of d-type setae on the left palp, was observed in a single individual.
Post-Embryonic Development inZaprionus indianus(Diptera: Drosophilidae)
Authors: Matavelli Cristiane , Zara Fernando José , Zuben Claudio José Von
Published: November 2013

The objectives of this study were to determine the number of instars of Zaprionus indianus Gupta, 1970, a fly that is considered a pest on fig plantations; analyze the pupation process; and characterize the morphology of the immature stages. This information would fill a gap in the knowledge regarding Z. indianus development. The post-embryonic development of this species was studied by using Dyar's rule to characterize the immature stages of the fly. In addition, the morphological structures were analyzed by scanning electron microscopy. Following Dyar's rule, Z. indianus exhibited three larval instars. Pupae were formed in higher numbers during the morning, and 5 d was the average time until adult emergence. The male:female sex ratio in this population was 1:1, with a higher emergence of females during the first 72 h. During the morphological analysis, the following structures were observed: (egg) chorionic cells, respiratory filaments, and micropyle; (larvae) body segments, intersegmental spines, antennae, the maxillary palp complex, sensilla, tubercles, and anterior and posterior spiracles; and (pupae) filaments that originated in the anterior spiracles and the presence of spines along these filaments. Some of these characteristics were slightly different from those observed in other drosophilids, which provides a taxonomic quality to these characteristics. In addition, these results may facilitate future studies on the biology, ecology, and control of this species.
Testing Developmental Plasticity in Aquatic Larvae ofCorethrella appendiculata(Diptera: Corethrellidae)
Authors: Blosser E M , Nishimura N , Lounibos L P
Published: November 2013

Insects with complex life cycles show a variety of developmental strategies when faced with low nutrient conditions requiring trade-offs in timing and nutrient storage. Previously documented strategies among insects include plasticity or canalization (fixation) of the pupation threshold, postthreshold developmental time, and adult size or stored resources. Using four models previously developed by Juliano et al. (2004), we tested the plasticity of these traits in the aquatic larvae of the frog-biting midge, Corethrella appendiculata Grabham. Rates of prey consumption and timing of pupation of fourth instar midges were compared across a range of prey densities. Model comparisons revealed that final instar C. appendiculata larvae exhibit a canalized pupation threshold followed by a canalized lengthy postthreshold period. Males entered the final instar earlier and reached a significantly lower threshold while females entered later and averaged more prey consumed daily, suggesting differing developmental strategies between sexes. Plasticity in body and egg clutch sizes of females from differing nutrient treatments was observed, but all females produced eggs autogenously. The canalized developmental pattern and long postthreshold period displayed in C. appendiculata is hypothesized to be related to the midge's preference for relatively permanent aquatic habitats.
The Fine Structure of the Spermatheca in Anopheles aquasalis (Diptera: Culicidae)
Authors: Pascini T V , Ramalho-Ortigäo J M , Martins G F
Published: November 2013

The vectorial capacity of mosquitoes is related to the reproductive output, and dependent on the ability of male spermatozoa to survive within the inseminated female. Mosquito females mate once, and immediately after mating, the male spermatozoa are transferred to and maintained in the ectodermic spermatheca. Mosquito spermathecae in culicines, especially of the yellowfever mosquito Aedes (Stegomyia) aegypti (L.), have been characterized in detail. In contrast, not much is known about this organ in anophelines. Here, the morphology of the spermatheca in the saltwater-tolerant mosquito Anopheles aquasalis Curry was investigated for the first time using a combination of light, confocal, and scanning and transmission electron microscopy. The spermatheca in An. aquasalis share many features with the three spermathecae present in Ae. aegypti, including a round-shaped reservoir and spermathecal duct glandular cells. However, differences such as the volume and cell types, as well as their numbers and distribution, were observed. The most remarkable difference seems to be the absence of a separated glandular unit as seen in Ae. aegypti. In An. aquasalis, the glandular cells are distributed along the reservoir wall, possibly representing a feature exclusive of anophelines. Together, these glandular cell units constitute the main secretory apparatus of An. aquasalis, and are the main source of secretions to nourish and maintain the viability of the gametes during the female's reproductive life span. Understanding the spermathecal organization and function will contribute to understand details of mosquito reproductive biology, and help answer questions related to the reproductive success of these major vectors of pathogens.
Functional Morphology of the Crop and Proventriculus of Sitophilus zeamais (Coleoptera: Curculionidae)
Authors: Sousa Géssica De , Scudeler Elton Luiz , Abrahão Josielle , Conte Helio
Published: November 2013

Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) is one of the most aggressive pests of stored grains, causing significant decrease in the nutritional quality of the grains and major losses in economic trade. The ability of this pest to damage grains and other products is directly related to the morphology of the alimentary canal. Considering the importance of the foregut in the digestion, this study aimed to describe the morphology of the crop and proventriculus in S. zeamais adults. The tissues were isolated, processed, and analyzed by using light microscopy, scanning electron microscopy, and transmission electron microscopy. The crop functioned as a storage organ, and its cells showed functional characteristics related to protein synthesis. High densities of prokaryotic microorganisms and spicules were found in the lumen. The proventriculus exhibited eight chitinous teeth, which were responsible for grinding and filtering food particles. This organ formed the stomodeal valve, which controlled the unidirectional flow of food through the alimentary canal. The alimentary canal is the primary surface of contact between the external environment and an insect's internal environment, and knowledge of its morphology is required to better understand the physiology of stored-grain insect pests.
A New Gynandromorph ofXylocopa frontaliswith a Review of Gynandromorphism inXylocopa(Hymenoptera: Apidae: Xylocopini)
Authors: Lucia Mariano , Gonzalez Victor H
Published: November 2013

A new case of gynandromorphism in bees is described and illustrated for the first time for Xylocopa (Neoxylocopa) frontalis (Olivier), a widely distributed carpenter bee in the neotropical region. The mixed gynandromorph, recorded from a single specimen from Paraguay, exhibits a mixture of male and female features in all tagmata. Previous literature records of gynandromorphs in Xylocopa Latreille are summarized, and the species identity of some gynandromorphs recorded for South America is revised. Including the specimen described herein, gynandromorphs are now known for a total of 12 species in Xylocopa, half of them in the neotropical subgenus Neoxylocopa.
Aphid Genotype Determines Intensity of Ant Attendance: Do Endosymbionts and Honeydew Composition Matter?
Authors: Katayama N , Tsuchida T , Hojo M K , Ohgushi T
Published: November 2013

Ant—aphid interactions are well-studied mutualisms, but surprisingly, the intraspecific variation in the degree of ant attendance of aphids has been less appreciated than interspecific variation. Honeydew composition is a key factor in determining aphids' traits in relation to the intensity of ant attendance, and composition may be altered by endosymbiotic bacteria. Here, we evaluate relationships among the intensity of ant attendance, honeydew composition, and aphids' endosymbionts. We found differences in the intensity of ant attendance and endosymbiont composition between clones of cowpea aphids (Aphis craccivora Koch). To investigate whether aphid genotype, endosymbionts, or both, influence honeydew composition, and the relative influence of these factors on the intensity of ant attendance, a secondary symbiont of the aphid, Arsenophonus, was removed from the clone exhibiting a lower degree of ant attendance. Then, the sugar and amino acid composition of honeydew were compared between different aphid genotypes and between same genotype with and without Arsenophonus. The experiments demonstrated that there was a difference in the sugar composition of honeydew between clones, but that Arsenophonus did not influence this difference. Furthermore, the intensity of ant attendance of the clone did not change after removing Arsenophonus. These results suggest that variation in the degree of ant attendance of this aphid is caused by aphid genotype, not by endosymbionts.
Resource Opportunities from the Nest of Dying Subterranean Termite (Isoptera: Rhinotermitidae) Colonies: A Laboratory Case of Ecological Succession
Authors: Chouvenc Thomas , Bardunias Paul , Efstathion Caroline A , Chakrabarti Seemanti , Elliott Monica L , Giblin-Davis Robin , Su Nan-Yao
Published: November 2013

Subterranean termites such as Coptotermes formosanus Shiraki inhabit underground nests consisting of a complex network of galleries resulting in a highly modified environment relative to the surrounding soils. A healthy colony can maintain homeostatic conditions within the nest, limiting opportunities for pathogens, parasites, and predators to exploit the termite colony as a resource. However, a stressed or senescent colony can display a lack of nest maintenance, leading to the colonization of the nest as an opportunistic niche by other organisms. In this study, we described the nest colonization by microbes and arthropods during the collapse of three dying C. formosanus laboratory colonies. The carton nest and the tunnel lining that are mostly made out of termite fecal material were invaded by a variety of fungi, and Acari and Collembolan populations quickly increased during the senescence phase of the termite colony, presumably scavenging on the fungal material. Finally, the carton colonized by fungal mycelia hosted numerous larvae of a sciarid fly, Bradysia sp. (Diptera). This fungus gnat used the decomposing carton material as a breeding site, and numerous adults of this fly were found hovering above the dying termite colony. Bradysia larvae also showed infestation by parasitic nematodes, suggesting the presence of multiple trophic levels in the resource utilization of the nest of a declining termite colony. We concluded that a dying subterranean colony represents a resource opportunity for scavenging organisms and that the nest structure represents an opening niche that initiates an ecological succession.
An Unusual Chrysopid Larva: Identification, Description, and Taxonomic Implications
Authors: Tauber Catherine A , Tauber Maurice J
Published: November 2013

Berchmansus is a small Neotropical genus in the green lacewing tribe Leucochrysini; its larvae and biology are unknown. Adults of Berchmansus adumbratus Navás were found in samples from the Smithsonian National Museum of Natural History Upper Amazonian forest canopy project; these samples came from palms at each of two widely separated Peruvian localities. The same samples also yielded specimens of an unusual leucochrysine larva. For a variety of reasons, we conclude that the larvae are likely conspecific with the adults. If our reasoning proves correct, they would represent the first reported larvae from the genus Berchmansus. Their anatomical features are consistent with either specialized trash-carrying or a naked lifestyle. Here we describe the larvae, and because they have many attributes not previously reported from leucochrysines, we reevaluate the suite of larval features that characterize the tribe. Our analysis illustrates that in both larval morphology and perhaps trash-carrying habits, the tribe Leucochrysini displays a much broader range of variation than previously recorded.
In Reply
Authors: O'Toole Jean , Jammallo Lauren S. , Miller Cynthia L. , Skolny Melissa N. , Specht Michelle C. , Taghian Alphonse G.
Published: November 2013

This reply addresses issues raised by Dylke et al. and encourages the lymphedema community to work collaboratively toward standardization in measuring lymphedema so as to facilitate generation of the data needed to move the field forward.
High‐performance genotypes in an introduced plant: insights to future invasiveness
Authors: Matesanz Silvia , Sultan Sonia E.
Published: November 2013

Maintaining high reproductive output in diverse conditions has consistently been found to promote invasiveness in introduced taxa. Following on this key observation, studies have compared the performance across environments of invasive vs. native congeners, and of introduced vs. native populations within invasive species. Performance differences among genotypes within introduced species have received far less attention, although such genetic variation could be critical to invasive potential. If an introduced species contains genotypes that can maintain high fitness across contrasting environments, such broadly adaptive, high‐performance genotypes could promote and shape the species' immediate spread across multiple habitats. Furthermore, their presence could lead to the evolution of greater aggressiveness in the species, as these high performers increase in frequency. We investigated the existence and distribution of high‐performance genotypes in Polygonum cespitosum, a newly invasive Asian annual. We raised 416 genotypes, collected from 14 North American populations, under resource‐rich conditions to identify potential high‐performance genotypes (the top 5% in total reproductive output). We then compared their fitness, life history, and functional traits to a random group of the remaining genotypes in three contrasting environments to ask the following: (1) Do consistently high‐performance genotypes (i.e., genotypes with high relative fitness in diverse conditions) exist within introduced‐range populations? (2) If so, do these high‐performance genotypes possess distinctive life history and/or functional traits? (3) Do these genotypes occur in all populations or in only a subset of populations?

Genotypes initially identified as high‐performance in favorable conditions also had higher reproductive output in resource‐limited environments. Their fitness advantage compared with control genotypes varied in magnitude from one environment to another but was significant within all three test environments. High‐performance genotypes shared a developmental syndrome characterized by rapid and high germination, fast seedling growth, early reproductive onset, and high reproductive allocation, but they did not differ in other functional traits.

P. cespitosum includes a subset of genotypes with accelerated development and significantly greater fitness in both favorable and stressful conditions. The nonrandom distribution of these high‐performance genotypes among populations in the species' introduced range highlights the importance of genotypic and population‐level variation for invasion dynamics.
Shifts in food quality for herbivorous consumer growth: multiple golden means in the life history
Authors: Bullejos Francisco José , Carrillo Presentación , Gorokhova Elena , Medina-Sánchez Juan Manuel , Balseiro Esteban Gabriel , Villar-Argaiz Manuel
Published: November 2013

Consumer growth can be affected by imbalances between the nutrient content of the consumer and its food resource. Although ontogenetic‐driven changes in animal composition are well documented, their potential consequences for the organism's sensitivity to food quality constraints have remained elusive. Here we show that the potential growth response of the copepodMixodiaptomus laciniatus(as %RNA and RNA:DNA ratio) to the natural gradient of seston carbon (C) : nutrient ratio is unimodal and stage specific. Solution of the equation given by the first derivative function provided the optimum C : nutrient ratio for maximum stage‐specific growth, which increased during ontogeny. The peakedness of the function indicated that animal vulnerability to suboptimal food quality decreased as juveniles reached adulthood. Consistent with these results, a field experiment demonstrated that potential consumer growth responded to variations in seston C : phosphorus ratio, and that early life stages were particularly vulnerable to suboptimal food quality.
Epigallocatechin‐3‐Gallate Attenuates Porphyromonas gingivalis Lipopolysaccharide‐Enhanced Matrix Metalloproteinase‐1 Production Through Inhibition of Interleukin‐6 in Gingival Fibroblasts
Authors: Wen Wan‐Chun , Kuo Po‐Jan , Chiang Cheng‐Yang , Chin Yu‐Tang , Fu Martin M.J. , Fu Earl
Published: November 2013

Background: Recent studies have shown that epigallocatechin‐3‐gallate (EGCG), a major constituent of green tea extract, exhibits effects of anti‐inflammation and antioxidation on periodontal inflammation. The present in vitro study examines the effect of EGCG on Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS)–enhanced expression of interleukin (IL)‐6 and matrix metalloproteinase (MMP)‐1, as well as the activation of nuclear factor‐kappa B (NF‐κB). Furthermore, the role of IL‐6 on LPS‐enhanced MMP‐1 production is evaluated using human gingival fibroblasts (HGFs).

Methods: HGFs were primary cultured from human gingiva specimens. The cytotoxicities of EGCG and LPS were tested by cell viability tests. The cellular mRNA expression of IL‐6 was determined by reverse‐transcription polymerase chain reaction, and the protein expression of MMP‐1 and IL‐6 was examined by enzyme‐linked immunosorbent assay. The cytosol expression and nuclear translocation of NF‐κB was evaluated by immunocytochemistry followed by confocal laser scanning microscopy.

Results: Pg LPS significantly increased MMP‐1 production in HGFs, whereas adding EGCG significantly attenuated this enhanced production of MMP‐1. LPS treatment also increased the mRNA and protein expression of IL‐6 and stimulated NF‐κB activation in HGFs. However, the addition of EGCG significantly attenuated the IL‐6 expression and NF‐κB activation. Supplemental addition of IL‐6 significantly enhanced cellular MMP‐1 production, whereas anti‐IL‐6 antibody inhibited LPS‐enhanced MMP‐1 production.

Conclusion: EGCG could attenuate Pg LPS‐enhanced production of MMP‐1 in HGFs, whereas this attenuation might be due to the inhibition of IL‐6 by EGCG.
Crestal Bone Changes at Teeth and Implants in Periodontally Healthy and Periodontally Compromised Patients. A 10‐Year Comparative Case‐Series Study
Authors: Rasperini Giulio , Siciliano Vincenzo Iorio , Cafiero Carlo , Salvi Giovanni E. , Blasi Andrea , Aglietta Marco
Published: November 2013

Background: Limited data exist on the longitudinal crestal bone changes around teeth compared with implants in partially edentulous patients. This study sought to compare the 10‐year radiographic crestal bone changes (bone level [BL]) around teeth and implants in periodontally compromised (PCPs) and periodontally healthy (PHPs) patients.

Methods: A total of 120 patients were evaluated for the radiographic crestal BL around dental implants and adjacent teeth at time of implant crown insertion and at the 10‐year follow‐up. Sixty patients had a previous history of periodontitis (PCPs), and the remaining 60 were PHPs. In each category (PCP and PHP), two different implant systems were used. The mean BL change at the implant and at the adjacent tooth at the interproximal area was calculated by subtracting the radiographic crestal BL at the time of crown cementation from the radiographic crestal BL at the 10‐year follow‐up.

Results: At 10 years after therapy, the survival rate ranged from 80% to 95% for subgroups for implants, whereas it was 100% for the adjacent teeth. In all eight different patient categories evaluated, teeth demonstrated a significantly more stable radiographic BL compared with adjacent dental implants (teeth BL, 0.44 ± 0.23 mm; implant BL, 2.28 ± 0.72 mm; P <0.05). Radiographic BL changes around teeth seemed not to be influenced by the presence or absence of advanced bone loss (≥3 mm) at the adjacent implants.

Conclusions: Natural teeth yielded better long‐term results with respect to survival rate and marginal BL changes compared with dental implants. Moreover, these findings also extend to teeth with an initial reduced periodontal attachment level, provided adequate periodontal treatment and maintenance are performed. As a consequence, the decision of tooth extraction attributable to periodontal reasons in favor of a dental implant should be carefully considered in partially edentulous patients.
Magnetic Resonance to Identify Permeability in Shale Reservoirs
Authors: Smith Charles H. , Ramakrishna Sandeep , Bray Jim
Published: November 2013

Unconventional reservoirs require a rigorous set of decision principles to achieve cost-effective and efficient completions. The oilfield definition of "unconventional reservoirs" includes any that exhibit permeability in the 0.01 md and tighter range. These permeability definitions become very tight as the reservoir includes a greater component of shale. Ultimately, shale resource reservoirs have permeability in the nanodarcy range, several orders of magnitude less than other unconventional resources.

Nuclear magnetic resonance (NMR) relaxation, or T2 measurement, has been used to establish permeability by direct application of the Bray-Smith permeability. There have been numerous comparisons of these permeability calculations to laboratory permeability and production rates. These comparisons have included wells in the unconventional range. The results have been quite favorable.

This paper explores the possibility that this calculation of permeability can be extended from the millidarcy to the nanodarcy range, proving useful in shale reservoirs worldwide. The basis of work was accomplished by comparing NMR results to laboratory core results. Additional refinement to the changes of calculation was performed using comparison to production rates from wells in the study.

The results illustrate the changes required to derive a useful solution of permeability directly from the NMR data in these shale reservoirs. A comparison of core results to this calculated permeability is also included.
Challenges of Refracturing Horizontal Wells in Unconventional and Tight Reservoirs
Authors: Strother David , Valadares Rodrigo , Nakhwa Amit D. , Pitcher Jason
Published: November 2013

The use of horizontal wells and multistage fracturing that is currently common in unconventional reservoirs first became popular during the early 2000s. Since then, the effectiveness and efficiency of horizontal wells has continued to be recognized. Because of the large number of these horizontal wells, significant opportunities for refracturing exist. Restimulation of these wells can allow the operator to increase production, as well as recoverable reserves, generally more economically than by installing new laterals or by infill drilling. An important challenge in refracturing these wells is to understand the rock system in which the well and the hydraulic fracture system are placed.

The major hurdle for net returns on any restimulation is effective candidate selection. This process involves not only choosing the right well, but also choosing the best zones within that well. Often, either a well (or zone) has not produced adequately or has been prolific and is in decline. However, there is no model that can predict production as accurately from unconventional reservoirs as from conventional ones. There are, however, measurable parameters that, when analyzed together, can indicate the relative potential of one zone to another. Therefore, to perform this analysis, any available data on the reservoir should be gathered. Then, well diagnostics are run to fill in the inevitable gaps in these data.

This paper discusses using a novel combination of cased-hole logging tools to gather these data. Using this combination to log the well after the first hydraulic fracturing treatment, the optimum restimulation candidate(s) can be determined. Then, whether to use existing perforation locations or to perforate new areas to cover non-stimulated rock can be decided; thus, optimizing the refracturing process. This selectivity of both candidates and zones during the refracture design can save time, costs, and resources, increasing the economic efficiency of the operation.
Coal Fractures and Present-Day Stress: Integration of Borehole Images and Sonic Anisotropy, Bowen and Surat Basins, East Australia
Authors: Halwa Leon , Donald Adam , Jones Anthony
Published: November 2013

Operators in the Bowen and Surat basins commonly use borehole images and to a lesser degree acoustic anisotropy to infer permeability anisotropy for use in field development; however it is not until now that other information from these technologies are fully unified to have potential to predict permeability. An ongoing challenge in these wells is to understand coal fractures and their relationship to present-day stress, as these geological factors define the permeability and ultimately production.

Borehole images are used to identify near-wellbore fracture discontinuities / fractures (coal cleats, tectonic fractures, and drilling-induced fractures), which can show a high density with a wide variation in azimuth. The polarization direction of the fast shear from borehole sonic logs will be a result of the dominant mechanism of stress and fractures in the far field; which is a net result of both fractures and present-day stress. It is uncertain, however whether the anisotropy is dominated by coal fractures or in-situ stress.

An improved method to characterize the complex relationship between fracture discontinuities and stress anisotropy has been applied to define the dominant mechanism. Orientations of coal fractures (cleats, tectonic fractures, and drilling-induced features) from near-wellbore imaging are combined and used to predict the far-field shear anisotropy direction from borehole sonic, and a comparison is made to the fast shear azimuth. Discrepancies between the direction of the fast shear and the fracture directions are then used to understand the net effect of fractures and present-day stress.

Preliminary results from comparing the anisotropy direction with the directions of stress and fractures in the study have shown that where anisotropy direction matches the fracture direction, there was lower permeability compared to when the anisotropy matches the maximum stress direction. Stress-dominated anisotropy, and in particular coals with a net contribution from both stress and fractures, showed higher permeability.
CBM Development in the Qinshui Basin: Hydraulic Fracture Complexities Revealed by Modeling Analysis and Microseismic Monitoring
Authors: Wu Jianguang , Sun Hansen , Liu Xinghui , Mayerhofer Mike , Zhang Ping , Wu Xiang , Zuo Jingluan
Published: November 2013

The Qinshui basin covers an area of approximately 42,000 km2 with coal resources and is one of the important regions for coal production and coalbed methane (CBM) exploitation in China. There are two major coalbeds that are important for CBM development. These coalbeds are laminated among sand, shale, and limestone formations and are located approximately from 200 to 1100 m in depth across the basin, with an average thickness between 3 and 6 m. This paper presents a case history of fracture evaluation for a CBM development project in the basin. In this study, fracture growth behavior was evaluated using fracture modeling and microseismic monitoring techniques. The instantaneous shut-in pressure (ISIP) for some treatments in the area of this study was well above the formation overburden stress. Closure stress obtained from diagnostic injection tests was high but lower than the overburden stress. Microseismic mapping results indicated significant fracture complexities, ranging from both confined and excessive height growth to asymmetric fracture growth and multidirectional fracture growth. An abundance of microseisms were detected, but most of them were located in the brittle sand and shale formations below and above the target coalbed. The complex fracture growth is believed to be caused by complex stress regimes and geologic settings in the study area. Fracture closure stress analysis from offset wells confirmed that stress variation was the primary reason for asymmetric fracture growth. Fracture modeling revealed that viscous fluids provided better fracture conductivity in the target coalbed than KCl water, as most proppant would settle below the target coalbed because of the poor transport capacity of water when KCl water was used alone. Based on the results from this study, improvements in fracture treatment design and well spacing should be considered. This paper demonstrates the benefits of an integrated approach to understanding hydraulic fracture growth behavior, which is important for developing a new CBMreservoir.
Influence of In-Situ Stresses on Fracture Stimulations in the Surat Basin, Southeast Queensland
Authors: Flottman Thomas , Brooke-Barnett Sam , Trubshaw Rod , Naidu Sai-Krishna , Kirk-Burnnand Elliot , Paul Pijush , Busetti Seth , Hennings Peter
Published: November 2013

The contribution investigates the relationship between in situ stress regimes, natural fracture systems and the propagation of induced hydraulic fractures in APLNG's (Australia Pacific Liquid Natural Gas) acreage within the Jurassic to Cretaceous Surat Basin in southeast Queensland. On a regional scale the data suggest that large basement fault systems have significant influence on the lateral and vertical interplay between geomechanical components which ultimately control permeability distribution in the area. At a local scale we show several case studies of significant in-situ stress variations (changes in tectonic regime from reverse to strike-slip, changes in horizontal stress orientation as well as changes in differential horizontal stress magnitude) which are identified from wireline image log interpretations and geomechanical models constructed from wireline sonic and density data. These variations are reflected in hydraulic fracture propagation, which is monitored through microseismic monitoring, tiltmeter monitoring. Reverse stress regimes result in the propagation of horizontal fractures; in areas of higher differential stress linear hydraulic fracture orientations are common, whereas in regions of lower differential stress the orientation of hydraulic fractures appears influenced by both stress and pre-existing fractures. The paper is relevant for fracture simulation in areas with complex in-situ stress regimes. The major technical contribution of the study is the use of geomechanical modelling for predicting hydraulic fracture propagation styles.
Knowing Where To Start: Assessment of Methane Resources with Petroleum Systems Modeling
Authors: Neber Alexander , Fuchs Thomas , Hantschel Thomas , Kadir Zailani , Rottke Wolf , Wygrala Björn
Published: November 2013

Gas hydrates are typically pressure- and temperature-controlled accumulations of mostly methane that occur in sediments at relatively shallow depths. They contain significant amounts of gas, perhaps more than any other conventional or unconventional source, and could ensure energy supplies for many years. Their production has not yet proved to be commercial, but recent progress in developing appropriate production methods is encouraging. There is, therefore, an increasing need to understand and predict gas hydrate distributions and resources; this can be done using a new module developed for industry-recognized petroleum systems modeling software.

Petroleum systems modeling software was designed to simulate the generation, expulsion, migration, accumulation, and loss of hydrocarbons in conventional petroleum systems. Recent technological advances in this software have produced a new hydrate module that can be applied to assess unconventional hydrocarbon resources. Pressure and temperature modeling is the core task of petroleum systems models, so they are also obviously suited to gas hydrate modeling.

The numerical simulation of accumulations in marine and permafrost environments is done with algorithms describing (1) the physical, thermodynamic, and kinetic properties of gas hydrates; (2) a kinetic model for the microbially mediated, low-temperature degradation of particulate organic carbon in sediments; and (3) the transport of dissolved and free-phase constituents in the pore fluid. In contrast to the resolution of conventional resource assessments, the temporal and spatial resolutions have been increased to enable simulation timesteps of 100 years and a minimum cell thickness of one decimeter.

The gas hydrate module was tested on the petroleum systems model of the Alaska North Slope region, where the hydrates have been drilled in fine-grained sand layers in marine and permafrost environments. Hydrate saturations and the methane source rock are well known in the drilled well. Simulations were run to predict the thickness of the Gas Hydrate Stability zone, the generation and migration of biogenic and thermogenic methane gas, the formation and dissociation of gas hydrates under marine and permafrost conditions, and the evolution of these properties over the geological past. The module is now being used by E&P companies and gas hydrate research centers in Japan, Korea, China, Germany, Norway, and the USA.
Characterisation of Fracture Permeability at Cow Lagoon-1, McArthur Basin, Northern Territory, Australia and Recommendations for Development of the Greater Cow Lagoon Structure
Authors: Mildren Scott , Clark Rachael , Holford Simon , Titus Luke
Published: November 2013

Resistivity image log interpretation of Armour Energy's Cow Lagoon-1 well in the Batten Trough of the McArthur Basin identified conductive and resistive fractures and faults throughout the interval. The 423 fracture surfaces and 55 faults interpreted display a dominant strike direction approximately 150°N and secondary fracture populations striking east-west around 060°N. Two borehole breakouts were also determined from image logs and used to constrain the mean maximum horizontal stress direction to 133°N. Contemporary stress distribution in the well is variable and fundamentally linked to the elastic properties of the sampled stratigraphy. Both strike-slip and extensional regimes are represented by the data.

Fracture susceptibility models indicate that the minimum ∆P to initiate a fracture is relatively high in all formations and generally exceeds 25 MPa. This reflects high strength calculated for these units and implies that creation of new fractures under the contemporary stress conditions is unlikely. Reactivation of existing fracture planes is more likely, with minimum ∆P exceeding 7 MPa in each model generated. Observations imply that many of the fractures are optimally oriented to be open or hydraulically conductive in the far field stress field.

Fracture density was shown to vary across the interpreted interval and also strongly correlates with stratigraphy. Steeper bedding dips consistently correlate with an increase in fracture density. Fault count was attributed to the stress conditions and modes of failure. Low fault count correlates with tensile failure, whilst high fault count implies shear failure.

Systematic analysis of the Cow Lagoon-1 data concludes that NNW striking fractures are critically oriented for shear reactivation in the far field stress environment. Such fractures correspond with high fault density and preferentially occur within low strength, low Young's Modulus, low differential stress units.