bluuebunny/crossref_metadata_2025 huggingface dataset:
Low-Frequency Sound Pressure and Transtympanic Endoscopy of the Middle Ear in Assessment of “Spontaneous” Perilymphatic Fistula
Authors: Pyykkö Ilmari , Selmani Ziane , Zou Jing
Published: August 2012

This study was designed to verify an eventual perilymphatic fistula (PLF) in 264 patients with sensorineural hearing loss (SNHL) and/or vertigo. The patients were exposed to a low-frequency sound stimulation (LFS) on posturography to objectively test Tullio’s phenomenon and Hennebert's sign. Endoscopes with 5 degree and 25 degree of visual angle and an outer diameter of 1.7 mm were used. The round window niche, with its foldings, oval window with stapes superstructure, a part of the facial recess and the area in the fissula ante fenestram were examined and video recorded. In one patient, we endoscopically verified a fistula in the round window membrane (resulting from a diving accident) that was covered with a fibrinous layer. In 4 cases, there was abnormal mucosal shining in the round window but without PLF. In 7 cases, the tympanic cavity could not be visualized because of the adhesive middle ear process, the abnormal anatomy, or the prominent exostoses of the ear canal prohibited vision. In 34 patients, LFS provoked unsteadiness on posturography without PLF. In 6 cases, a postoperative middle ear infection was recorded. No permanent tympanic membrane perforation occurred. It is unlikely that disease entity of “spontaneous PLF” exists. Tympanoscopy should be regarded as the first choice when a PLF is suspected.
Tooth Surface Loss and Associated Risk Factors in Northern Saudi Arabia
Authors: Al-Zarea Bader K.
Published: August 2012

Aim. To evaluate tooth surface loss (TSL) severity and associated risk factors in a representative sample of Saudi adults. Materials and Methods. Four hundred TSL patients (200 females and 200 males) participated in this study. Each patient completed a comprehensive questionnaire interview (using a modified Tooth wear Assessment Questionnaire) and then examined for the severity of TSL (using ordinal scale). Results. Seventy-five percent of participants demonstrated attrition, 90% had erosion, 15% had abrasion, and 95% had more than one type of TSL. The most common risk factors were consumption of acidic food/drinks (78%), parafunctional habits (70%), and unilateral chewing (50%). 77% of participants demonstrated grade 2 TSL. Males demonstrated greater TSL severity (). Age, systemic disease, number of remaining teeth, acidic food/drinks, bruxism/parafunction, biting objects, facial pain/tenderness, sour taste, exposure to dust, unilateral chewing, using dental abrasives, and brushing frequency/technique had significant relationship with TSL severity (). Conclusions. TSL has a multifactorial aetiology. Parafunction, gastrointestinal problems, and diet were the most common aetiological factors reflecting changes to stressful modern life-styles, eating/drinking habits, and behaviours. Gender didn’t influence the aetiology of TSL; however males demonstrated more TSL severity. Patients’ age had significant correlation to TSL severity.
Optimization of Multiple Roughness Characteristics of Chemically Deposited Ni-P-W Coating Using Weighted Principal Component Analysis
Authors: Roy Supriyo , Sahoo Prasanta
Published: August 2012

The present investigation deals with the chemical deposition of Ni-P-W coating on mild steel substrate and optimization of multiple surface roughness characteristics on the basis of different coating process parameters. Three coating parameters which are varied to have the optimum condition are concentration of nickel source, concentration of reducing agent, and concentration of tungsten source. Five different roughness parameters, namely, centre line average (Ra), root mean square roughness (Rq), skewness (Rsk), kurtosis (Rku), and mean peak line spacing (Rsm) are considered. Weighted principal component analysis (WPCA) method is adopted to convert the multiple-response problem into a single performance index and Taguchi L27 orthogonal array is used. ANOVA is performed to find the significance of the each coating process parameters and their interactions. The EDX analysis, XRD analysis, and SEM are performed to study the composition and structural aspects.
Structure and Composition of Ba-W-Ti-O Ceramics Interface Regions Formed at Ultrasonic Vibration
Authors: Karban O. , Kanunnikova O. , Khazanov E. , Salamatov E. , Khasanov O. , Taranov A.
Published: August 2012

The study of Ba-W-Ti-O ceramics has shown that the structure and composition of their interface regions differ from those in the grain bulk owing to the diffusion of tungsten atoms to the grain surface during sintering. They are determined by the conditions of compacting of dry nanopowders (compaction pressure and power of ultrasonic action) and vary in a nonmonotonic way. Increasing the pressure during dry static compacting and exposure to ultrasound result in the formation of a complex structure of fragments and boundaries between them, increasing the acoustic density and decreasing the intergranular boundary thickness. This affects the travel time of the phonon pulse through the sample, which allows one to determine the density and thickness of the grain boundaries by the method of phonon spectroscopy.
Age Variance in the Survival of United States Pediatric Leukemia Patients (1973–2006)
Authors: Holmes L. , Opara F. , Des-Vignes-Kendrick M. , Hossain J.
Published: August 2012

Background. Age at diagnosis remains an important prognostic factor in pediatric leukemia. However, it is not fully understood which prognostic factors are related to its effect on survival. This study aimed to assess the effect of age at diagnosis on pediatric leukemia survival in the United States (US). Methods. We utilized the Surveillance Epidemiology and End Results (SEER) data of the diagnosed pediatric leukemia patients (n=15215) from 1973–2006. Life table, Kaplan-Meier, log rank test, and Cox proportional hazard methods were used to examine the data.
Results. The overall 5-year survival was 67.9%. Infants and children of 18 and 19 years had the highest risk of dying, with a rapid declining risk of death at age of 1 year that continued until age of 3 years and thereafter a steady trend of increased risk of death. The increased risk of dying was associated with boys, T-cell type and more than one primary tumor, P < 0.0001. There was significant variability in survival by the age group at diagnosis. Compared to age group <1 year, children of ages 1–4 years, 5–9 years, 10–14 years, and 15–19 years were 76% (adjusted hazard ratio (AHR) = 0.24, 99% CI = 0.21–0.28), 69% (AHR = 0.31, 99% CI = 0.26–0.36), 46% (AHR = 0.54, 99% CI = 0.46–0.62), and 18% (AHR = 0.82, 99% CI = 0.70–0.95) less likely to die, respectively. Conclusion. The age at tumor diagnosis was a single most potent prognostic factor of childhood leukemia survival, with infants and children of age group 15–19 years experiencing the poorest survival. This significant variability persisted after adjustment for the effect of other covariates. Therefore, there is a need to identify other prognostic factors that are associated with age in order to provide a meaningful explanation of the impact of age on pediatric leukemia survival in the US.
Green's Second Identity for Vector Fields
Authors: Fernández-Guasti M.
Published: August 2012

The second derivative of two vector functions is related to the divergence of the vector functions with first order operators. Namely, .
Studies of Atmospheric Parameters during SW Monsoon Period Associated with Severe Cyclone Aila and Lightning Occurrence over Ranchi Region
Authors: Srivastava Abhay , Kumar Manoj , Dwivedi Arun K.
Published: August 2012

A number of events are happening every time in the atmosphere in which much of them are randomly generated. Parameters are varying daily like temperature, humidity, electric field, and wind speed. Variation on surface layer parameters, events thunderstorms, earthquake, volcanoes, cyclone, tsunami, and so forth are occurring. Study and correlation between surface layer parameter and occurrence are greatly required in current research scenario. A comparative study about atmospheric parameters has been done just after the Aila; in the day when lightning occurred and correlation coefficients between these parameters are observed.
A case of bilateral, spontaneous absorption of lenses
Authors: Ahmad Syed Shoeb , Rahim Affra Abdul , Ghani Shuaibah Abdul
Published: August 2012

Spontaneous absorption of lenses or cataracts is rare. We report a case of bilateral spontaneous lens absorption in a 36-year-old woman for which no cause could be determined despite extensive laboratory testing.
Immediate loss of vision due to retinal pigment epithelial tear after anti-angiogenesis treatment of pigment epithelial detachment
Authors: Cornish Kurt Spiteri , Harvey Robert
Published: August 2012

Intravitreal injection of ranibizumab, an antivascular endothelial growth factor (VEGF) drug, is currently the primary treatment for wet age-related macular degeneration (AMD) in the UK. Use of ranibizumab for the treatment of isolated pigment epithelial detachments (PEDs) without the presence of an occult choroidal neovascular membrane has not been studied in a randomized controlled fashion and is strictly off-label. One possible complication of intravitreal injection of the drug is retinal pigment epithelial (RPE) tear. To date, the etiology of RPE tear associated with intravitreal injection is unknown; it could be attributed to rapid contraction of the neovascular membrane by fibrosis, perhaps triggered by the drug. We report a case of an RPE tear occurring less than a minute after intravitreal injection of ranibizumab for a fibrovascular PED. To our knowledge, this is the first report of such a case.
Idiopathic pupillary capture 7 years after extracapsular cataract extraction and intraocular lens implantation
Authors: Ramos Juan , Jurado Venancio
Published: August 2012

Pupillary capture is a pathology commonly associated with traumatic or inflammatory processes of the eye. We present a case of idiopathic pupillary capture, 7 years after extracapsular cataract extraction and intraocular lens implantation. This case highlights the need for ongoing patient surveillance, especially in elderly patients who are less able to detect subtle changes in their vision.
Keratoprosthesis in congenital hereditary endothelial dystrophy after multiple failed grafts
Authors: Haddadin Ramez I. , Dohlman Claes H.
Published: August 2012

Congenital hereditary endothelial dystrophy (CHED) has historically been managed with penetrating keratoplasty (PK), with moderate success, and, more recently, with Descemet's stripping endothelial keratoplasty (DSEK). The possibility of repeated graft failures with CHED, however, makes alternative surgical procedures desirable. To our knowledge, this is the first reported use of a keratoprosthesis for management of CHED in a patient with multiple graft failures. The patient has been successfully followed for 5 years, has 20/30 vision, and no glaucoma.
Chorioretinal atrophy after electrical injury
Authors: Zablocki Gregory J. , Hagedorn Curtis L.
Published: August 2012

A 26-year-old-man who had suffered a severe electrical injury 3 years previously presented with blurred vision in his left eye caused by a posterior subcapsular cataract with nuclear sclerotic changes and peripapillary chorioretinal scarring. The pattern of retinal atrophy surrounding the optic nerve suggests a possible path of electrical current to the eye and demonstrates the selective tissue damage that may occur in electrical injuries.
Pigment deposition on the central aspect of the posterior lens capsule in pigmentary dispersion
Authors: Nagarajaiah Shubha , Shun-Shin Georges Adrien
Published: August 2012

We describe a case of an increasing pigmentary plaque on the posterior surface of the lens during follow-up of a case of pigment dispersion syndrome and suggest that this is a new sign of pigment dispersion.
Anterior capsular rupture following blunt ocular injury
Authors: Gremida Anas , Kassem Iris , Traish Aisha
Published: August 2012

A 10-year-old boy suffered a large, oblique anterior capsular tear following blunt injury to his right eye. The boy was followed daily for hyphema resolution and progressive traumatic cataract formation. After the hyphema had resolved, the lens was removed using an anterior approach and an intraocular lens was placed with excellent visual outcome.
A 6-week-old baby boy with discharge
Authors: Cupp David G.
Published: August 2012

A 6-week-old non-Hispanic white boy presented to the Neonatal Intensive Care team of Tulane University Medical Center with a 3-week history of yellow-grey discharge from both eyes; he was otherwise in no distress. He was born by normal vaginal delivery at 37 weeks gestational age after an uneventful pregnancy. He was in the care of foster parents, and the medical history of his biological parents was unknown. There was no other ocular history. He had no known allergies, and his immunizations were up-to-date. He had pulmonary hypertension, a patent ductus arteriosa, and had undergone repair of a diaphragmatic hernia at 1 week of age. For 4 days prior to presentation, he had been administered erythromycin elixir, 400 mg orally four times daily, without improvement in ocular discharge.
A 39-year-old woman with unilateral metamorphosias
Authors: Ribeiro Lígia , Barge Sidnei , Silva Luís , Brandão Arnaldo , Meira Dália
Published: August 2012

A 39-year-old white woman presented to the Centro Hospitalar Vila Nova de Gaia with a chief symptom of blurred vision and metamorphopsias in the left eye of several days' duration. Her past medical history was unremarkable. She was not taking any medications. She was a nonsmoker, did not use alcohol, and had no pets. Her family history was unremarkable except for her mother having hypertension.
Boston Keratoprosthesis: expanding the boundaries
Authors: Harissi-Dagher Mona
Published: August 2012

The Boston Keratoprosthesis (KPro) has enjoyed good results in the adult population, particularly through its rapid clearing of the visual axis, its excellent retention rate, and the paucity of postoperative complications in recent years. Design modifications, enhanced surgical technique, and improved postoperative management have made keratoprosthesis surgery a reality in the twenty-first century and an excellent alternative for poor PK candidates.
CD133+, CD166+CD44+, and CD24+CD44+ Phenotypes Fail to Reliably Identify Cell Populations with Cancer Stem Cell Functional Features in Established Human Colorectal Cancer Cell Lines
Authors: Muraro Manuele Giuseppe , Mele Valentina , Däster Silvio , Han Junyi , Heberer Michael , Cesare Spagnoli Giulio , Iezzi Giandomenica
Published: August 2012

Increasing evidence that cancers originate from small populations of so-called cancer stem cells (CSCs), capable of surviving conventional chemotherapies and regenerating the original tumor, urges the development of novel CSC-targeted treatments. Screening of new anticancer compounds is conventionally conducted on established tumor cell lines, providing sufficient material for high-throughput studies. Whether tumor cell lines might comprise CSC populations resembling those of primary tumors, however, remains highly debated. We have analyzed the expression of defined phenotypic profiles, including CD133+, CD166+CD44+, and CD24+CD44+, reported as CSC-specific in human primary colorectal cancer (CRC), on a panel of 10 established CRC cell lines and evaluated their correlation with CSC properties. None of the putative CSC phenotypes consistently correlated with stem cell-like features, including spheroid formation ability, clonogenicity, aldehyde dehydrogenase-1 activity, and side population phenotype. Importantly, CRC cells expressing putative CSC markers did not exhibit increased survival when treated with chemotherapeutic drugs in vitro or display higher tumorigenicity in vivo. Thus, the expression of CD133 or the coexpression of CD166/CD44 or CD24/CD44 did not appear to reliably identify CSC populations in established CRC cell lines. Our findings question the suitability of cell lines for the screening of CSC-specific therapies and underline the urgency of developing novel platforms for anticancer drug discovery.
Serum- and Stromal Cell-Free Hypoxic Generation of Embryonic Stem Cell-Derived Hematopoietic Cells In Vitro, Capable of Multilineage Repopulation of Immunocompetent Mice
Authors: Lesinski Dietrich Armin , Heinz Niels , Pilat-Carotta Sandra , Rudolph Cornelia , Jacobs Roland , Schlegelberger Brigitte , Klump Hannes , Schiedlmeier Bernhard
Published: August 2012

Induced pluripotent stem cells (iPSCs) may become a promising source for the generation of patient-specific hematopoietic stem cells (HSCs) in vitro. A crucial prerequisite will be the availability of reliable protocols for the directed and efficient differentiation toward HSCs. So far, the most robust strategy for generating HSCs from pluripotent cells in vitro has been established in the mouse model involving ectopic expression of the human transcription factor HOXB4. However, most differentiation protocols include coculture on a xenogenic stroma cell line and the use of animal serum. Involvement of any of both would pose a major barrier to the translation of those protocols to human autologous iPSCs intended for clinical use. Therefore, we asked whether long-term repopulating HSCs can, in principle, be generated from embryonic stem cells without stroma cells or serum. Here, we showed that long-term multilineage engraftment could be accomplished in immunocompetent mice when HSCs were generated in serum-free medium without stroma cell support and when hypoxic conditions were used. Under those conditions, HOXB4+ embryonic stem cell-derived hematopoietic stem and progenitor cells were immunophenotypically similar to definitive bone marrow resident E-SLAM+ (CD150+CD48−CD45+CD201+) HSCs. Thus, our findings may ease the development of definitive, adult-type HSCs from pluripotent stem cells, entirely in vitro.
Phytochemical Screening and In-Vitro Evaluation of Antioxidant Activities of Various Extracts of Leaves and Stems of Kalanchoe crenata
Authors: Manisha Bhatti  , Anjoo Kamboj  , Ajay Kumar Saluja
Published: August 2012

Many diseases are associated with oxidative stress caused by free radicals. Current research is directed towards finding naturally occurring antioxidants of plant origin. Kalanchoe crenata Andr. (Crassulaceae), commonly known as "never die" or "Dog's liver," has been traditionally used for the treatment of ailments, such as, earache, smallpox, headache, inflammation, pain, asthma, palpitations, convulsion, and general debility. The aim of present research deals with phytochemical screening and in-vitro evaluation of antioxidant activities of the leaves & stems of K.crenata. Method: Successive extracts of leaves & stems was subjected for phytochemical screening. The preliminary screening reports the presence of saponins, phytosterols, flavanoids, phenols and alkaloids in the extracts. Various extracts of K.crenata leaves & stems was studied in-vitro for total antioxidant activity, for scavenging of nitric oxide, hydrogen peroxide, the antioxidant capacity by phosphomolybdenum, reducing power determination and determination of phenolic and flavonoid content in the extracts. 1,1-Diphenyl-2-picrylhydryzyl (DPPH) scavenging activity or the hydrogen donating capacity was quantified in presence of stable DPPH radical on the basis of Blois method. Nitric Oxide (NO) radical scavenging method was performed in the presence of nitric oxide generated from sodium nitroprusside using ascorbic acid as standard in both methods. The phenolic content was determined by using Folin-Ciocalteu reagent and flavonoid content was determined by aluminum chloride. Result: The radical scavenging activity was found to dose dependent. Thus extract has been established as an antioxidant. The reducing capacity serves as significant indicator of antioxidant activity. The reducing power was found to increase with the increasing concentration of extract. The 100mg plant powder yielded 0.34, 0.49, 0.72, 0.98%w/wand 0.15, 0.23, 0.39, 0.56%w/w phenolic content in the benzene, chloroform, acetone, ethanol extracts of leaves and stems respectively using gallic acid as standard. Plant contains about 0.19, 0.29, 0.48, 0.64%w/w and 0.11, 0.17, 0.32, 0.47 %w/w of flavonoid content in the benzene, chloroform, acetone, ethanol extracts of leaves and stems respectively using quercetin as standard. Conclusion: The present study provides evidence that different extracts of K.crenata leaves and stems is potential source of antioxidant activity. The extracts were found to contain phenolic compounds which could be responsible for the antioxidant properties. So K. crenata traditional use is justified in the present research work.
What information structure tells us about individual/stage-level predicates
Authors: Jiménez-Fernández Angel
Published: August 2012

The goal of this paper is to explore the lexical-syntactic structure of copulative constructions and argument small clauses within the framework proposed by Gallego & Uriagereka (2011) for the Individual-Level/Stage-Level distinction (Carlson 1988, Kratzer 1995) and implement their theory by claiming that there is a crucial correlation between IL/SL constructions and their information structure. I argue that IL subjects are topics (and hence this is a categorical construction, following Kuroda 1972, Milsark 1977 and Raposo & Uriagereka 1995), whereas in SL constructions the topic may either be the subject or a silent spatiotemporal argument (their construction being thetic). I show the topic nature of IL subjects in contexts of specificity and subextraction. I ultimately derive the IS of IL/SL constructions from their lexical-syntactic structure and identify the type of topic here as an Aboutness-Topic (in the sense of Frascarelli & Hinterhölzl 2007, Lambrecht 1994, Erteschik-Shir 1997).

Keywords: individual-level/stage-level predicates, copulas, small clause, central-coincidence/terminal coincidence prepositions, topic, specificity, subextraction
Aspecto léxico, sentido y colocaciones: los nombres de sentimiento
Authors: Sanromán Begoña
Published: August 2012

El objetivo de este estudio es mostrar que la distinción aspectual entre predicados estativos individuales y episódicos puede aplicarse a los nombres que expresan sentimiento en español. Partimos de dos premisas: 1) los nombres de sentimiento son predicados estativos y 2) existen dos clases de nombres de sentimiento: por una parte, los nombres de causa interna (NCI), por ejemplo, respeto o envidia, denotan sentimientos que se originan en el experimentador como resultado de un pensamiento a través del cual se evalúa un objeto del mundo; por otra, los nombres de causa externa (NCE) como asombro o desesperación representan sentimientos que surgen en el experimentador como reacción a un hecho externo. Como hipótesis de trabajo defendemos la existencia de correlaciones entre las dos clases de nombres de sentimiento, NCI y NCE, de un lado, y las dos clases de predicados estativos, individuales y episódicos, de otro, de tal modo que los NCI se comportan como predicados individuales y los NCE, como predicados episódicos. Dado que la diferencia fundamental entre los predicados individuales y los episódicos viene determinada por su capacidad o incapacidad para expresar los límites espaciales y/o temporales de la situación por ellos aludida, mostraremos que solo los NCE coocurren con expresiones delimitadoras de tiempo y/o espacio. Como pruebas para diagnosticar el comportamiento aspectual de los nombres de sentimiento, utilizamos las colocaciones, codificadas por medio del aparato formal de las funciones léxicas (FFLL) de Mel’čuk (1996) y recogidas, en su mayor parte, en el Diccionario de colocaciones del español (DiCE).

 

Palabras clave. Predicados individuales y predicados episódicos; nombres de sentimiento; colocaciones; funciones léxicas; aspecto léxico.
Galicia upwelling revisited: out-of-season events in the rias (1967–2009)
Authors: Álvarez I , Prego R , DeCastro M , Varela M
Published: August 2012

Over the last decades several studies have been conducted on upwelling along the Galician coast that have significantly improved the knowledge of this process. These investigations showed that upwelling along this coast is a frequent phenomenon during the spring and summer months, pumping colder Eastern North Atlantic Central Water into the rias. Nevertheless, several upwelling events in autumn and winter have been characterized in the Galician rias, indicating that the upwelling process along the Galician coast is not a phenomenon restricted to spring and summer. In this study the recurrence of these upwelling events has been reviewed from published articles and analyzed from 1967 to 2009 along the western and northern Galician coasts in terms of an upwelling index. The highest mean number of days under favorable upwelling conditions per month was observed during spring and summer on the western (18–26 days) and northern (12–14 days) coasts. During autumn and winter the number of days was lower (11–18 days, western coast; 8–10 days, northern coast) although not negligible, showing the possibility of observing upwelling events during this period. In fact, during these months a significant probability of observing favorable upwelling conditions along both coasts (26%) was found, though the most probable situation corresponded to unfavorable upwelling conditions (44%). The results thus revealed that these events cannot be considered isolated episodes. Upwelling processes in the rias should be observed under favorable conditions, such as prevalence of northerly wind at the adjacent western Galician shelf, independently of the season.
Gonad index and larval development of the sand dollar Dendraster excentricus (Echinodermata; Echinoidea) in Baja California, Mexico
Authors: Olivares-Bañuelos T , Figueroa-Flores S , Carpizo-Ituarte E
Published: August 2012

The sand dollar Dendraster excentricus has been extensively used in diverse studies in Baja California (Mexico). This study shows annual variations in the gonad index and describes larval development under laboratory conditions of D. excentricus. Over a period of one year, adult sand dollars (6.73 ± 0.56 cm diameter and 23.22 ± 6.90 g) were collected monthly. Both the monthly analysis of the gonad index (male and female) and the measure of mature eggs were considered to estimate the reproductive period of the sand dollar in Punta Banda Estuary (Baja California). Our results suggest that D. excentricus has two maximum reproductive peaks, one during the early spring and another during the summer, although viable gametes were obtained in the laboratory year round. Larval development took 21–23 days from fertilization to metamorphosis under laboratory conditions (19 ± 2 ºC, salinity 33.5). The blastula stage was observed 5 h postfertilization, while four-armed echinopluteus larvae, with an average size of 387.00 ± 23.25 ?m (from aboral to dorsal arms), were observed two days after fertilization. A different larval stage was attained approximately every two days. Eight-armed echinopluteus larvae were 744.60 ± 69.45 µm in size. The completely developed juvenile rudiment was detected 18 days after fertilization and metamorphosed larvae were observed 72 h after induction. These results, while not new for the species, show the reproductive behavior and larval period for the D. excentricus populations associated with an estuary at the southern limit of its distribution, and will be useful to document variation in the response of species of ample geographic distribution in global change scenarios.
Phenology and alginates of two Sargassum species from the Caribbean coast of Colombia
Authors: Camacho O , Hernández-Carmona G
Published: August 2012

The genus Sargassum (Phaeophyceae) forms large beds on rocky shores of the Colombian Caribbean, showing large seasonal fluctuations in biomass that are related to upwelling events in the area. This study describes the phenology of two benthic species of Sargassum from the Caribbean coast of Colombia, and presents a preliminary assessment of the alginate concentration and properties of viscosity and gel strength to determine their potential as an exploitable resource. Samples were collected during 2007 in the Santa Marta area. The first species was identified at genus level as Sargassum sp. The highest values of biomass and abundance of receptacles were recorded in April and the lowest between June and February. The other species was Sargassum cymosum. It showed higher biomass and persisted a longer time than Sargassum sp. In spite of this, the biomass and reproductive period of both species were markedly seasonal and low during most of the year. Alginate yield was relatively high in both species, compared to that reported for other Sargassum species. The viscosity of the alginates was very low and may thus have only few applications in the industry; however, the gel strength of the alginates of both species was competitive, compared with other commercial algal products. This study suggests that while these two species of Sargassum in Colombia are potential candidates for the commercial production of alginates in regard to some applications, the marked seasonality of the species advises caution for a sustainable exploitation.
Nutrient removal using two species of mangrove (Rhizophora mangle and Laguncularia racemosa) in experimental shrimp (Litopenaeus vannamei) culture ponds
Authors: Moroyoqui-Rojo L , Flores-Verdugo FJ , Hernández-Carmona G , Casas-Valdez M , Cervantes-Duarte R , Nava-Sánchez EH
Published: August 2012

The nutrient removal capacity of two species of mangrove (Rhizophora mangle and Laguncularia racemosa) was assessed in shrimp (Litopenaeus vannamei) culture ponds. One pond contained R. mangle seedlings and another L. racemosa seedlings, while a third (control pond) was left without seedlings. Treatment ponds contained 20 floating platforms with 720 mangrove seedlings. Water was pumped from the estuary into the ponds. Nutrient (NO3–, NO2–, NH4+, and PO4–3) concentrations from the pond effluents were analyzed during the water exchange every 10 days. The results showed that L. racemosa removed 83.4% of dissolved inorganic nitrogen (DIN) and 45% of PO4 and R. mangle removed 79% of DIN and 40% of PO4, while 30% of DIN and 23% of PO4 was removed in the control pond. The flux of nutrients from the influent water to the ponds was 7269 g of N and 3095 g of P. In the ponds with mangroves, the nutrients were reduced to 1018–1071 g of N and 609–724 g of P. In the control pond, the effluent water nutrient concentrations were 5564 g of N and 1583 g of P. The nutrients accumulated in the mangrove tissue were 18,014–16,711 g of N and 5976–5832 g of P. Volatilization of ammonium and adsorption of phosphorus by sediments were 17,298–18,570 g of N and 6249–6268 g of P, and in the control pond, 30,022 g of N and 10,922 g of P, respectively. The final length for L. racemosa was 48 cm and the root length was 54 cm. For R. mangle, the final length was 38 cm and the root length was 46 cm. Shrimp survival was 70%, with individuals reaching 10.4 g in weight and 12.2 cm in length. We concluded that the nutrient removal percentage in ponds with mangrove seedlings was higher than in the pond without seedlings, improving water quality and reducing nutrients in the effluent.
Interannual changes in the fish community abundance on the west coast of Campeche, Mexico
Authors: Ayala-Pérez LA , Terán-González GJ , Ramos-Miranda J , Flores-Hernández D
Published: August 2012

The biodiversity and abundance of commercially important biotic resources on the west coast of Campeche (Mexico) is recognized. The main extraction activity is seabob shrimp fishing. This paper aims to analyze and discuss changes in the abundance of the fish community in two annual cycles by statistical analysis. Between February 2003 and January 2004 (cycle 1) and between February 2006 and January 2007 (cycle 2), 37 sites were visited monthly. Physical and chemical parameters were registered and nekton samples were collected by a trawl net. In cycle 1, 49,177 individuals (631.62 kg total weight) were caught and the fish community was represented by 94 species. In cycle 2, 26,386 individuals (407.07 kg total weight) and 94 species were caught. At spatial scale, the fish community abundance values were 0.01–0.23 ind m–2, 0.08–3.02 g m–2, and 7.12–45.45 g ind–1 in cycle 1, and 0.007–0.11 ind m–2, 0.13–1.71 g m–2, and 5.61–45.64 g ind–1 in cycle 2. Highest abundance was recorded during the dry season in cycle 1, but during the rainy season in cycle 2. There were no significant differences in temperature and salinity between the two cycles, but an analysis of variance revealed significant differences between seasons. Significant differences were founded when the matrix of number of individuals per species and month of both cycles was analyzed by multidimensional scaling.
Diet composition of batoids on the continental shelf off Nayarit and Sinaloa, Mexico
Authors: Navarro-González JA , Bohórquez-Herrera J , Navia AF , Cruz-Escalona VH
Published: August 2012

Since elasmobranchs are frequently apex predators in marine ecosystems, information on their diet is essential for understanding trophic relationships in these systems. Trophic similarity between six batoid species (Rhinoptera steindachneri, Rhinobatos glaucostigma, Dasyatis dipterura, Urotrygon aspidura, U. nana, and U. rogersi) was examined by analyzing the stomach contents of 140 individuals. Specimens were caught by the commercial shrimp fishery in the central Mexican Pacific. In total, 88.6% of the stomachs were completely to partially full, allowing the identification of 77 types of prey. The primary dietary components were crustaceans, followed by annelids and mollusks. Values of diet breadth for the six species indicated low diversity in prey items. Diet similarity suggested two trophic guilds: R. glaucostigma, U. nana, and U. aspidura belong to the cancritrophic guild (P < 0.05) and U. rogersi and D. dipterura to the annelidcrustacean guild. Rhinoptera steindachneri showed no evident pattern of association (feeding primarily on ophiuroids). In light of these results, we argue that a distribution of alimentary resources (niche partitioning) between the six species favors their coexistence.
Numerical modeling of seasonal and mesoscale hydrography and circulation in the Mexican Central Pacific
Authors: Pantoja DA , Marinone SG , Parés-Sierra A , Gómez-Valdivia F
Published: August 2012

Based on results from a ROMS numerical model, the dynamics of the Mexican Central Pacific was studied during three years (2003–2005). The model reproduces the mean and seasonal variability of sea surface temperature, as well as mesoscale eddies and meanders from satellite observations. The model adequately represents the main currents in the region: California Current, Mexican Coastal Current, and Gulf of California currents. The Gulf of California currents are linked to the intensificiation of the Mexican Coastal Current and interact in such a way that the lateral shear generates eddies at the entrance to the Gulf of California. The mesoscale eddies were found to have a depth of ~200 m. The eddies generated in the area (internal Rossby radius of deformation, Rd = 40 km) had a diameter L of ~300 km, an orbital speed of 20–30 cm s–1, and a westward translation speed of ~4 cm s–1. Eddies are considered from intermediate to big (L≈  7.5 Rd, Ro << 1), show geostrophic dynamics, and present a westward drift due to Coriolis variation with latitude (beta effect). The size of the eddies seems to be related to the weakening of the meridional component of wind stress during the North American monsoon.
Distribution of the Antillean manatee (Trichecus manatus manatus) in the Alvarado Lagoon System (Veracruz, Mexico)
Authors: Daniel-Rentería IC , Serrano A , Sánchez-Rojas G
Published: August 2012

The Antillean manatee (Trichechus manatus manatus) is considered endangered in Mexico. Local extinctions have been documented in the northern Gulf of Mexico, and the only remaining population with a northern distribution is found in the Alvarado Lagoon System (ALS). The objective of this study was to determine manatee distribution in ALS. The system covers an area of 267,010 ha and includes hundreds of lagoons, floodable areas, and dozens of rivers. To detect manatees, systematic line transects were done in a boat 7.6 m in length, totaling 332.6 h of search effort with an average of 7.38 h d–1 in 45 surveys. There was a total of 13 manatee sightings: seven direct sightings, five with hydrophones, and one with a side-scan sonar. For each record the geographical coordinates were taken and integrated in a geographical information system to analyze their distribution. Manatee distribution was not uniform throughout the study area. Manatees were sighted in very specific areas of ALS considered part of their habitat, mainly in areas with inland water bodies, in some estuarine and marshy areas, and in some wetlands with vegetation generally in appropriate condition. This lagoon system is very important for manatee conservation since it is the last site with viable populations in Veracruz and the northern Gulf of Mexico.
An In Situ Experimental‐Numerical Approach for Characterization and Prediction of Interface Delamination: Application to CuLF‐MCE Systems
Authors: Kolluri Murthy , Hoefnagels Johan P. M. , Samimi Mohammad , van Dommelen Hans , van der Sluis Olaf , Geers Marc G. D.
Published: August 2012

Prevention of delamination failures by improved design calls for accurate characterization and prediction of mixed‐mode interface delamination. In this paper, a combined in situ experimental‐numerical approach is presented to fully characterize the interface behavior for delamination prediction. The approach is demonstrated on two types of industrially‐relevant interface samples – coated copper lead frame‐black molding compound epoxy and uncoated copper lead frame‐white molding compound epoxy, – for which the delamination behavior is characterized in detail using a miniaturized in situ SEM mixed‐mode bending setup and simulated using a newly developed self‐adaptive cohesive zone (CZ) finite element framework. To this end, mixed‐mode load‐displacement responses, fracture toughness versus mode angle trends, and real‐time microscopic observations of the delamination front are analyzed to determine all CZ parameters. The various simulation results are found to be in agreement with experiments for the range of mode mixities accessible, demonstrating the ability of the characterization procedure to accurately obtain the cohesive properties of different interfaces, as well as the stability and efficiency of the self‐adaptive CZ framework.
Following Chemical Charge Trapping in Pentacene Thin Films by Selective Impurity Doping and Wavelength‐Resolved Electric Force Microscopy
Authors: Smieska Louisa M. , Pozdin Vladimir A. , Luria Justin L. , Hennig Richard G. , Hines Melissa A. , Lewis Chad A. , Marohn John A.
Published: August 2012

Charge trapping is one of several factors that limit the performance of organic electronic materials, yet even in pentacene, a prototypical small‐molecule semiconductor, the precise chemical nature of charge trapping remains poorly understood. Here the effects of three chemical trap‐precursor candidates are examined by layering thin‐film pentacene transistors with different pentacene defect species. The resulting charge trapping is studied in each device via scanning‐probe electric force microscopy coupled with variable‐wavelength sample illumination. Firstly, it is found that layering with pentacen‐6(13H)‐one (PHO) readily produces uniform charge trapping everywhere in the transistor channel, as expected for an active blanket‐deposited trap‐precursor. However, layering with 6,13‐dihydropentacene (DHP) produces fewer, more‐isolated traps, closely resembling the surface potential distribution in pristine pentacene thin films. Secondly, the rates of trap‐clearing versus illuminating wavelength (trap‐clearing spectra) are measured, revealing enhanced trap‐clearing rates at wavelengths assigned to the absorption of either pentacene or the charged trap species. The trap‐clearing spectrum for the PHO‐layered sample closely resembles the spectrum obtained from pentacene aged in a working transistor, while the trap‐clearing spectrum for the DHP‐layered sample resembles the spectrum observed in pristine pentacene. We conclude that PHO competently creates traps in pentacene that match the expected trap‐clearing spectrum for degraded pentacene, while DHP does not, and that the chemical trap species in aged pentacene is very likely PHO+.
Simulation studies on a rotating ring disk electrode system: Role of supporting electrolyte in determination of relevance of ionic migration
Authors: Guha Sirshendu
Published: August 2012

Most of the past theoretical works with the rotating ring disk electrode (RRDE) system have been restricted to situations where supporting electrolyte concentration is large enough so that the effects of migration of ionic species in the solution becomes negligible. In this work, effects of ionic migration have been investigated for a RRDE system by solving the differential equations describing mass transfer in presence of ionic migration using numerical technique. Two cases were considered for simulation, presence and absence of migration of ionic species. Results indicate that in presence of migration, collection efficiency of a RRDE system increases for all electrode geometries and concentration boundary layer thickness reduces. Results also indicate that collection efficiency is dependent on electrode geometries. The system chosen for simulation is copper sulfate solution of 0.1 (M) concentration with little supporting electrolyte. It is also noticed that migration effect remains important for supporting electrolyte concentration as high as 0.1 (M). Limiting current condition was assumed. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1390–1399, 2013
Cognitive impairment and cortical degeneration in neuromyelitis optica
Authors: Saji Etsuji , Arakawa Musashi , Yanagawa Kaori , Toyoshima Yasuko , Yokoseki Akiko , Okamoto Kouichirou , Otsuki Mika , Akazawa Kohei , Kakita Akiyoshi , Takahashi Hitoshi , Nishizawa Masatoyo , Kawachi Izumi
Published: August 2012

Objective:

Neuromyelitis optica spectrum disorder (NMOsd) is an inflammatory and demyelinating syndrome characterized by optic neuritis and myelitis. Several magnetization transfer magnetic resonance imaging (MRI) studies have revealed abnormalities in normal‐appearing gray matter in NMOsd. The aim of this study is to elucidate the characteristics and pathogenesis of cognitive impairment and neurodegeneration in NMOsd brains.

Methods:

Fourteen Japanese patients with serologically verified NMOsd, 17 patients with multiple sclerosis (MS), and 37 healthy controls were assessed with the Rao's Brief Repeatable Battery of Neuropsychological Tests (BRBN). Using 128 tissue blocks from 6 other cases of NMOsd, 3 cases of MS, and 4 controls without central nervous system involvement, we performed quantitative analysis of cortical neuronal loss and layer‐specific changes in NMOsd.

Results:

In BRBN assessments, 57% of NMOsd patients and 47% of MS patients had impaired performance on at least 3 cognitive tests. Cognitive impairment in NMOsd was common even in the limited form of disease, indicating that NMOsd may progress insidiously from early stages of disease. Neuropathological assessments showed neuronal loss in cortical layers II, III, and IV, with nonlytic reaction of aquaporin‐4 (AQP4)‐negative astrocytes in layer I, massive activated microglia in layer II, and meningeal inflammation in NMOsd brains. All NMO cases showed no evidence of cortical demyelination.

Interpretation:

We demonstrate cognitive impairment and substantial cortical neuronal loss with unique AQP4 dynamics in astrocytes in NMOsd. These data indicate pathological processes consisting not only of inflammatory demyelinating events characterized by pattern‐specific loss of AQP4 immunoreactivity but also cortical neurodegeneration in NMOsd brains. ANN NEUROL 2013.
Knee laxity after staircase exercise predicts radiographic disease progression in medial compartment knee osteoarthritis
Authors: Miyazaki Tsuyoshi , Uchida Kenzo , Sato Mitsuhiko , Watanabe Shuji , Yoshida Ai , Wada Makoto , Shimada Seiichiro , Kuiper Jan Herman , Baba Hisatoshi
Published: August 2012

Objective

To evaluate whether increased laxity of the knee during daily physical activities such as stair climbing is associated with progression of knee joint osteoarthritis (OA).

Methods

During the years 2001–2003, 136 patients with bilateral primary medial compartment knee joint OA were enrolled in this prospective study. Baseline data collected were body mass index (BMI), muscle power, radiographic joint space width, mechanical axis on standing radiography, and anteroposterior (AP) knee laxity before and after physical exercise. After 8 years of followup, 84 patients were reexamined to assess radiographic changes. Radiographic disease progression was defined as progression of >1 grade on the Kellgren/Lawrence scale.

Results

AP knee laxity increased significantly after stair climbing. Patients with OA progression and those without progression did not differ significantly in age, sex, baseline quadriceps muscle strength, mechanical axis, joint space width, and AP knee laxity before exercise. The 2 groups of patients did, however, differ significantly in baseline BMI and change in AP knee laxity due to exercise. The risk of progression of knee OA increased 4.15‐fold with each millimeter of increase in the change in AP knee laxity due to exercise and 1.24‐fold with each point increase in the BMI.

Conclusion

Our results indicate that patients with OA progression have significantly greater changes in knee joint laxity during physical activities and a higher BMI than patients without OA progression. These findings suggest that larger changes in knee laxity during repetitive physical activities and a higher BMI play significant roles in the progression of knee OA.
Tipping the lysine methylation balance in disease
Authors: Black Joshua C. , Whetstine Johnathan R.
Published: August 2012

Genomic instability is a major contributing factor to the development and onset of diseases such as cancer. Emerging evidence has demonstrated that maintaining the proper balance of histone lysine methylation is critical to preserve genomic integrity. Genome‐wide association studies, gene sequencing, and genome‐wide mapping approaches have helped identify mutations, copy number changes, and aberrant gene regulation of lysine methyltransferases (KMTs) and demethylases (KDMs) associated with cancer and cognitive disorders. Structural analysis of KMTs and KDMs has demonstrated the drugability of these enzymes and has led to the discovery of small molecule inhibitors. Use of these inhibitors has allowed better understanding of the biochemical properties of KMTs and KDMs and demonstrated potential for therapeutic use. This review will highlight the methyl modifications, KMTs and KDMs associated with cancer and neurological disorders and how KMT and KDM and the potential for treatment of these conditions with small molecule inhibitors. © 2012 Wiley Periodicals, Inc. Biopolymers 99: 127–135, 2013.