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Resumen Introducción: Los arrecifes coralinos están entre los ecosistemas más importantes y valiosos del planeta. Sin embargo, en las últimas décadas han sufrido procesos de degradación, reduciendo su cobertura coralina y complejidad topográfica. La competencia alga-coral es un proceso ecológico importante en la dinámica de los arrecifes coralinos y estudiarla permite entender la resiliencia en estos sistemas. Objetivo: Determinar el efecto de la herbivoría sobre la competencia coral-alga bajo diferentes escenarios (empleando una combinación de enfoques descriptivos y experimentales) y dos épocas climáticas en Capurganá, Caribe colombiano (área de conservación marina, Hope Spot). Métodos: Entre julio 2018 y abril 2019, se evaluó el rol de la herbivoría, mediante un experimento de exclusión - no exclusión en 48 individuos coralinos bajo diferentes escenarios de interacción entre Siderastrea siderea y sus algas circundantes (tratamientos), la mitad de los corales juveniles se cubrieron con cajas metálicas de 2 400 cm2 fijas al bentos. Los tratamientos consistieron en: T1= Control, T2= Remoción de algas, T3= Daño coralino, T4= Juveniles en contacto con algas artificiales, T5= T2 + T3, T6= T2 + T4, T7= T3 + T4 y T8= T2 + T3 + T4. Resultados: Después de un muestreo total de nueve meses, se encontró diferencias entre escenarios con y sin exclusión (P= 0.006) y la época climática (P= 0.032), el crecimiento coralino fue mayor cuando las algas fueron removidas en presencia de herbívoros (DMS de Fisher, mean ± SE 9.871 ± 8.298) y la aparición de algas fue mayor dentro de las jaulas que fuera de ellas, mientras que el tratamiento de competencia no presentó interferencia en el crecimiento (P= 0.155). Los juveniles fueron colonizados por algas cuando su tejido fue dañado y sin herbívoros (mean ± SE 9.359 ± 3.901). Hubo diferencias en el crecimiento coralino entre épocas (época seca: Media 0.0029 ± SD 0.0243 cm2/día y época húmeda: Media 0.0022 ± SD 0.0161 cm2/día). Conclusiones: Los resultados indican que el crecimiento coralino depende de la presencia de herbívoros que regulan el crecimiento, reproducción y supervivencia de las algas; actualmente este proceso está siendo interrumpido como consecuencia de la sobrepesca en estos ecosistemas, por lo cual, es importante destacar que la reducción de la herbivoría resultó en un crecimiento más rápido de algas, demostrando la importancia crítica de la herbivoría para el resultado de la interacción competitiva. Sin embargo, algunas algas podrían ser benéficas para los juveniles coralinos cuando su abundancia es lo suficientemente grande para protegerlos de la depredación por peces y suficientemente pequeña para no reducir considerablemente su crecimiento. Estos procesos son decisivos en estos ecosistemas, particularmente en zonas donde éste es relevante desde una perspectiva ecológica, social, cultural y económica, lo cual hace que estos estudios sean importantes para la correcta implementación de manejo integrado en zonas arrecifales ayudando a la recuperación, protección y conservación del arrecife, y promoviendo la disminución de la pesca de herbívoros. Abstract Introduction: Coral reefs are among the most important and valuable ecosystems on the world. However, in recent decades they have been under siege by degradation processes reducing their coral cover and topographic complexity. The coral-algae competition is an important ecological process in the dynamics of coral reefs thus studying is pivotal for understanding the resilience in these systems. Objective: To determine the effect of herbivory on coral-algae competition under different scenarios (using a combination of descriptive and experimental approaches) and two climatic seasons in Capurganá Bay, Colombian Caribbean, in a marine conservation area (Hope Spot). Methods: Between July 2018 and April 2019, the role of herbivory was evaluated, performing an exclusion - no exclusion experiment in 48 coral individuals under different scenarios of interaction between Siderastrea siderea and its surrounding algae (treatments), half of the juvenile corals were covered with 2 400 cm2 metal boxes fixed to the benthos. The treatments consisted of : T1= No manipulation (control), T2= Algae removal, T3= Coral damage, T4= Juveniles in contact with artificial algae, T5= T2 + T3, T6= T2 + T4, T7= T3 + T4 and T8= T2 + T3 + T4. Results: After nine months of experiments, differences were found between with and without exclusion (P= 0.006) and the climatic season (P= 0.032), it was found that coral growth was higher when algae were removed in the presence of herbivores (Fisher’s LSD, mean ± SE 9.871 ± 8.298) and the appearance of algae was greater inside the cages than outside them, while the competitive treatment did not show growth interference (P= 0.155). Algae colonized juveniles when their tissue was damaged and herbivory was excluded (mean ± SE 9.359 ± 3.901). There were differences in coral growth between seasons, being higher in the dry season (Average 0.0029 ± SD 0.0243 cm2/day) than in the wet season (Average 0.0022 ± SD 0.0161 cm2/day). Conclusions: The coral growth depended on the presence of herbivores that regulate the growth, reproduction, and survival of algae; currently, this process is being interrupted as a result of overfishing in the reef ecosystems. However, some algae could be beneficial for juvenile corals when their abundance is large enough to protect them from fish predation and small enough not to significantly reduce their growth. These processes are decisive in these ecosystems, particularly in areas where it is relevant from an ecological, social, cultural and economic point of view, which makes these studies important for the correct implementation of integrated management in reef areas helping recovery, protection, and conservation of the reef promoting the decrease of herbivore fishing.

espanolEl reclutamiento coralino permite inferir sobre elestado de salud y la resiliencia del ecosistema arrecifal. El uso de sustratos artificiales in situ facilita evidenciar la llegada de nuevos individuos y/o el repoblamiento de corales escleractinios dentro del sistema. El arrecife El Ingles, en Isla Fuerte (Caribe colombiano), esta expuesto a la influencia de los rios Sinu y Magdalena. Alli se cuantifico el reclutamiento coralino ensustrato artificial usando placas de terracota de 15 x 15 cm en tres profundidades (4-6, 12-14, 22-24 m), con recambio cada dos meses durante un ano. Asi mismo, se recolecto el sedimento depositado en la superficie de las placas en cada muestreo. Seregistraron 30 reclutas en total (1 a 6 reclutas por muestreo), con diferencias en la densidad de estos a traves del tiempo, siendomayor entre junio-agosto, lo cual coincide con la reduccion en la cantidad de sedimento, mientras que por profundidad no hubo diferencias en dicha variable. La cantidad de sedimento, por otra parte, presento variaciones en el tiempo y con la profundidad. Solo en la zona profunda del arrecife se encontro una correlacion inversa (r2=–0,34, p=0,04, n=36) entre la densidad de reclutas yla cantidad de sedimento, lo que indica que a mayor carga de sedimento, menor densidad de reclutas. El hecho de que el reclutamiento coralino registrado fuera menor en comparacion con otros arrecifes evaluados en el Caribe sugiere la vulnerabilidad de este caso concreto a la alta sedimentacion proveniente del rio Sinu, particularmente de limos+arcillas entre febrero-abril-junio. No obstante, el reclutamiento registrado sugiere que especies adultas dominantes y sobrevivientes en el arrecife, como A. tenuifolia, P. astreoides, P. poritesy S. siderea, mantienen su actividad reproductiva EnglishCoral recruitment can be used as an indicator ofthe health status and resilience of the reef ecosystem. The use of artificial substrates can be used to evaluate the recruitment of individuals and/or the system repopulation by scleractinian corals. El Ingles reef, in Isla Fuerte (Colombian Caribbean) isbeingexposed to the influence of Sinu and Magdalena rivers. Coral recruitment was quantified in artificial substrates using terracotta plates of 15 x 15 cm, at three depths (4-6, 12-14, 22-24 m) with replacement every two months for a year. Additionally,sediment deposited on plate surface was collected for each sample. A total of 30 recruits (1 to 6 recruits for sample) were registered, showing differences between the density of recruits over time, being higher between June-August coinciding with a reduction in the sediment loads. No differences in recruits density by depth were observed. The quantity ofsedimentation showed differences over time and depth; only an inverse correlation (r2=–-0.34, p=0.04, n=36) between recruits density of and sediment amount indeep areas was found in the reef, indicating that the larger load the sediments produced a negative effect on recruits. Coral recruitment registered was low compared with other reefs in the Caribbean, suggesting its vulnerability to high sedimentation by the Sinu River, particularly silt+clays during February-April-June. However, registered recruitment suggests that dominant and survival adult species in the reef asA. tenuifolia, P. astreoides, P. poritesand S. siderea, maintain their reproductive activity

Lumbar epidural steroid injections are used to manage low back and leg pain (ie, sciatica). Utilization of the procedure is increasing, with Medicare spending for lumbar epidural procedures topping $175 million annually. Few prospective randomized controlled trials have clearly demonstrated the efficacy of epidural steroid injections; many have shown conflicting results. Several studies show favorable short-term outcomes with epidural steroid injection for radicular pain, but less conclusive results are achieved >6 months. Methodologic flaws limit interpretation of results from most scientific studies. As a tool for predicting surgical outcome, epidural spinal injection has been found to have a sensitivity between 65% and 100%, a specificity between 71% and 95%, and a positive predictive value as high as 95% for 1-year surgical outcome. Despite inconclusive evidence, when weighing the surgical alternatives and associated risk, cost, and outcomes, lumbar epidural steroid injections are a reasonable nonsurgical option in select patients.

The morphological plasticity and community responses of algae competing with corals have not been assessed. We evaluated eight morphological characters of four species of stoloniferous clonal filamentous turf algae (FTA), including Lophosiphonia cristata (Lc) and Polysiphonia scopulorum var. villum (Psv) and the composition and number of turf algae (TA) in competition for space with the coral Orbicella spp. under experimental and non-manipulated conditions. All FTA exhibited morphological responses, such as increasing the formation of new ramets (except for Psv when competing with O. faveolata). Opposite responses in the space between erect axes were found when Psv competed with O. faveolata and when Lc competed with O. annularis. The characters modified by each FTA species and the number and composition of TA species growing next to coral tissue differed from that of the TA growing at ≥3 cm. The specific and community responses indicate that some species of TA can actively colonise coral tissue and that fundamental competitive interactions between the two types of organisms occur within the first millimetres of the coral−algal boundary. These findings suggest that the morphological plasticity, high number and functional redundancy of stoloniferous TA species favour their colonisation of coral tissue and resistance against coral invasion.

Objective: The weight of a child’s backpack is widely thought to contribute to back pain. No studies directly support numerous general guidelines on backpack use. This study is designed to investigate the relationship between back pain and backpack weight in an American school population. Study Design: Blinded, cross-sectional, observational study. One hundred and eighty four schoolchildren in the third grade and middle school levels filled out a questionnaire on individual habits and back pain. Height, weight, and backpack weight were measured by blinded observers. Results: While there was a relationship between age and back pain (45.6% of middle schoolers, vs. 15.3% of 3rd graders, p < 0.01), the relationship between back pack weight and back pain was not significant. Those who carried other objects (musical instruments, sports bags, etc.) had have increased back pain (p = 0.019), but this relationship disappeared with age adjustment. Conclusion: Contrary to media hype, laws, and position statements, this first study of the relationship between back pack weight and pain suggests that there is no independent relationship between back pack use and back pain in American school children.

We evaluated the effects of competition for space between mixed turf algae (MTA) and the hermatypic coral Montastraea faveolata Ellis and Solander (1786) using reciprocal transplantation of 17 cm 2 cores and by measuring the response of some biological parameters of the coral: zooxanthellae density, mitotic index, chlorophyll a (Chl a) concentration, and tissue thickness. Mitotic index and Chl a zooxanthellae -1 were not significantly affected by the competition, but zooxanthellae density, Chl a cm -2 , and tissue thickness were reduced in M. faveolata tissue surrounded by algae. Lower values have been reported for these three biological parameters of scleractinian corals subjected to stress conditions. Stressed M. faveolata surrounded by MTA were completely overgrown in 6-9 months. MTA frequently formed unattached cushions before the algae were attached to the coral skeleton. The cushions could be affecting M. faveolata by shading the coral tissue beneath the algae and probably causing stress to the tissue. Trapped sediments in the cushions may also be affecting M. faveolata by trapping sediments that cause smothering or burial of coral tissue. This is the first demonstration that algae directly stress a coral species and that MTA can be superior competitors than M. faveolata under experimental conditions. M. faveolata is sensitive to algae and bacteria, and the outlook for this coral species is poor if deleterious conditions act together in the Caribbean Sea.

Cervical spondylotic myelopathy is a common cause of compressive spinal cord dysfunction. The typical course involves either a gradual or an episodic increase in symptoms and neurologic deficits, with impairment evolving over a period of months to years. Acute neurologic deterioration in conjunction with cervical spondylosis has been described almost exclusively in traumatic situations such as disk herniation. We report a case of an acute, nontraumatic onset of tetraplegia in association with cervical spondylosis. A 56-year-old man developed tetraplegia during a 1-hour nap, with loss of volitional control of his extremities, impaired sensation below the C3 dermatome, and increased muscle tone. Magnetic resonance imaging of the cervical spine revealed canal stenosis and increased T2 signal within the cord. This case report describes the rehabilitation course for this patient and reviews the clinical spectrum of onset and progression of cervical spondylotic myelopathy.

Se revisaron muestras de macroalgas de un hábitat pocas veces analizado (colindante a la parte basal del tejido vivo de los corales Acropora palmata y Diploria strigosa) y de una zona de México poco conocida florísticamente (parte Sur del Caribe mexicano), con base a lo cual se reporta a Corallophila verongiae (Rhodophyta), Derbesia fastigiata (Chlorophyta) y Hincksia onslowensis (Phaeophyta) como nuevos registros de macroalgas para la costa del Atlántico mexicano. Además, se reporta a Lophosiphonia obscura (Rhodophyta) como nuevo registro para la parte costera continental del Atlántico mexicano, ya que sólo se había registrado hace más de 40 años para Arrecife Alacranes, sitio alejado aproximadamente 180 km al norte de Puerto Progreso, Yucatán. Aunque las especies de macroalgas no presentaron estructuras reproductoras, probablemente por tener crecimiento clonal y estar invadiendo tejido coralino, los caracteres morfológicos permitieron su identificación con certeza. Con excepción de la primera especie, las otras no se habían registrado creciendo sobre corales. Tomando en cuenta estos nuevos registros, el total de especies de macroalgas registradas hasta este estudio para el Caribe mexicano es de 546, incluyendo 307 Rhodophyta, 171 Chlorophyta y 68 Phaeophyta. Esta zona tropical y la costa templada de Baja California conforman las dos zonas florísticas marinas más ricas de México.

Objective: To establish interrater reliability for paraspinal muscle needle electromyography study with both monopolar and concentric needles in symptomatic and asymptomatic persons and to further establish normative data for paraspinal needle study. Design: At a university spine center, participants with and without radiating low back pain were evaluated with the mini-paraspinal mapping paraspinal needle technique by an unblinded and a blinded electromyographer. Results: In the symptomatic group, the intraclass correlation coefficient between concentric and monopolar needles was 0.793; between monopolar needles, it was 0.876; and between concentric needles, it was 0.966. In the asymptomatic group, the mean total score was 0.25. Conclusions: The good interrater reliability with the same needle type helps support the validity of the needle electromyography study of the paraspinal muscles. The good correlation between the concentric and monopolar needles shows the data published using monopolar needle data also apply to studies using paraspinal needle electromyography with concentric needles. The low score with the asymptomatic group reaffirms that using a cutoff score of >2 as abnormal has a false-positive rate of

Combining DICOM software and internet access using desktops, an accessible and low-cost PACS system is conveniently available to the medical community.