Trunk Segments Research Articles

Characteristics of Postural Muscle Activity in Response to A Motor-Motor Task in Elderly

The purpose of the current study was to evaluate postural muscle performance of older adults in response to a combination of two motor tasks perturbations. Fifteen older participants were instructed to perform a pushing task as an upper limb perturbation while standing on a fixed or sliding board as a lower limb perturbation. Postural responses were characterized by onsets and magnitudes of muscle activities as well as onsets of segment movements. The sliding board did not affect the onset timing and sequence of muscle initiations and segment movements. However, significant large muscle activities of tibialis anterior and erector spinae were observed in the sliding condition (p < 0.05). The co-contraction values of the trunk and shank segments were significantly larger in the sliding condition through the studied periods (p < 0.05). Lastly, heavy pushing weight did not change the timing, magnitude, sequence of all studied parameters. Older adults enhanced postural stability by increasing the segment stiffness then started to handle two perturbations. In conclusion, they were able to deal with a dual motor-motor task after having secured their balance but could not make corresponding adjustments to the level of the perturbation difficulty.

Cellular morphology of leg musculature in the water bear Hypsibius exemplaris (Tardigrada) unravels serial homologies.

Tardigrades (water bears) are microscopic, segmented ecdysozoans with four pairs of legs. Lobopodous limbs that are similar to those seen in tardigrades are hypothesized to represent the ancestral state of Panarthropoda (Tardigrada + Onychophora + Arthropoda), and their evolutionary history is important to our understanding of ecdysozoan evolution. Equally important is our understanding of the functional morphology of these legs, which requires knowledge of their musculature. Tardigrade musculature is well documented but open questions remain. For example, while the muscular organization of each trunk segment and its legs is unique, three of the four trunk segments are nevertheless relatively homonomous. To what extent, then, do leg muscles show segmental patterns? Specifically, which leg muscles are serially repeated and which are unique? The present study addresses these questions using a combination of techniques intended to visualize both the overall layout and fine structure of leg muscles in the eutardigrade Hypsibius exemplaris. In doing so, we propose serial homologies for all leg muscles in each of the four legs and reveal new details of their cellular structure and attachment sites. We compare our results to those of previous studies and address the functional implications of specialized muscle cell morphologies.

Longitudinal Development of Segmental Trunk Control in Full Term and Preterm Infants- a Pilot Study: Part I

ABSTRACTPurpose: No previous study examined trunk control development in preterm infants. The present study examined the longitudinal development of segmental trunk control from 4 to 12 months of (corrected) age in preterm infants in comparison with full-term infants.Methods: Thirty-one preterm infants and 30 full-term infants were recruited. All infants were tested monthly using the Segmental Assessment of Trunk Control and the Alberta Infant Motor Scale at 4, 8 and 12 months of age.Results: Segmental trunk control development was significantly delayed in the preterm infants. Statistically significant positive correlations were found between trunk control status and gross motor skills.Conclusion: This was first study showing that segmental trunk control development was significantly different in preterm infants. Segmental trunk control and gross motor performance were coupled in young infants. A dual focus on training upright trunk control and specific motor skills may maximise therapy outcomes for infants with motor delay.

Echinoderes ultraabyssalis sp. nov. from the Kuril-Kamchatka Trench – the first hadal representative of the Kinorhyncha (Kinorhyncha: Cyclorhagida)

A new species of echinoderid kinorhynchs, Echinoderes ultraabyssalis sp. nov. collected from oxidized brown clay at the deepest depression of the Kuril-Kamchatka Trench, North-West Pacific, is described and illustrated using light and electron microscopy. This new representative of the largest kinorhynch genus is characterized by the unique set of spines and tubules and can be easily distinguished from other congeners. The first trunk segment shows remarkably wrinkled posterior margin with parallel cuticular notches; the second trunk segment bears pair of adhesive tubules in both sexes; trunk segment 5 with pair of tubules in lateroventral position; trunk segment 8 with lateral accessory tubules; trunk segment 9 with tubules in laterodorsal position; acicular lateroventral spines on trunk segments 6–9 and two acicular middorsal spines on trunk segments 6 and 8. This species is also well recognized by the presence of tooth-like middorsal protuberance on trunk segment 11. Echinoderes ultraabyssalis sp. nov. constitutes the deepest kinorhynch species described so far (9411–9541 m) and the first hadal representative of the Kinorhyncha in the World Ocean.

Ontogeny and shape change of the phacopid trilobite Calyptaulax

AbstractMajor transitions in trilobite ontogeny have historically been defined based on the number and distribution of trunk segments, and articulation between the trunk and cephalon. This study documents additional morphological change across the meraspid-holaspid transition on the Ordovician phacopid trilobiteCalyptaulax strasburgensis. An extensive dataset of silicified cranidia and pygidia collected from the mid-Ordovician Edinburg Formation of Virginia was subjected to a series of multivariate analyses, with a primary focus on the intersections and termini of furrows. Multivariate regression of partial warp scores demonstrates statistically significant change in allometric growth patterns over the course of development. These changes are concentrated in earlier instars, but are coincident in cranidia and pygidia. This sharp decrease in the rate of allometry, present in both tagmata, is expressed as significant breakpoints derived from a segmented regression, with the largest portion of allometric change found in the pre-breakpoint individuals. The term holeidos is proposed to describe the completion of form during trilobite development, independent of the completion of the thorax. The most dramatic change in shape during this period of ontogeny includes lateral glabellar expansion through deflection of the axial and palpebral furrows, possibly reflecting a change in the feeding habit during later development. Other morphological changes include the development of a more angular appearance to the anterior portion of the glabella, and anterior migration of the pygidial anterior margin. The appearance of these growth patterns inCalyptaulaxextends the temporal range of these changes, some of which have only been documented in Devonian phacopids.

Longitudinal Development of Segmental Trunk Control in Full Term and Preterm Infants- a Pilot Study: Part II

ABSTRACTPurpose: To explore the relationship between segmental trunk control and specific gross motor skills at 4, 8 and 12 months of (corrected) age in young infants.Methods: Thirty-one preterm infants and 30 full-term infants were recruited by convenience. All infants were tested using the Segmental Assessment of Trunk Control and the Alberta Infant Motor Scale at 4, 8 and 12 months of age.Results: The gross motor function in supine at 4 months and in the standing position at 12 months was significantly delayed in the preterm infants. Positive correlations were found between segmental trunk control levels and specific motor skills in prone, supine, sitting and standing positions at 8 and 12 months of age.Conclusion: This report was the first to demonstrate the association between segmental trunk control and specific gross motor skills in young infants. This new information provides clinicians with greater understanding about infant development.

Analysis of Center of Mass and Gravity-Induced Vertebral Axial Torque on the Scoliotic Spine by Barycentremetry

Study DesignRetrospective observational study. ObjectivesTo determine the mass distribution along the scoliotic trunk using barycentremetry and its relationship with vertebral axial rotation and torque. Summary of the Background DataDeformity progression in adolescent idiopathic scoliosis (AIS) is not yet fully understood, but gravity load on the spine could play a role. Barycentremetry allows to characterize body mass distribution in standing position, which could provide a better understanding the mechanisms of progression. Methods81 subjects (27 healthy adolescents and 53 AIS patients) underwent biplanar radiography and 3D reconstruction of the spine and body envelope. Position of the gravity line was estimated, as well as trunk segmental centers of mass COMs at each vertebral level and resulting axial torques to each vertebra. ResultsThe COM of all trunk segments was less than 1 cm from the gravity line in the frontal plane for healthy subjects, and less than 1.5 cm for AIS patients. Vertebral axial torque was 0.7 ± 0.5 Nm in healthy subjects, 2.9 ± 2.1 Nm at the junctional vertebrae of AIS patients and 0.5 ± 0.5 at the apex. A strong association was found between high torque and high intervertebral rotation at junctions, with low torque and low intervertebral axial rotation at the apex. ConclusionResults suggest that AIS patients can maintain the COM of each body segment close to their gravity line, irrespective of the severity and asymmetry of their deformity. Moreover, torque analysis shed some light on the importance of junctional vertebrae in the spinal deformity and, potentially, in the vicious cycle determining scoliosis progression. Level of EvidenceLevel III.

Dungeons and dragons: Two new species and records of Kinorhyncha from anchialine cenotes and marine lava tubes

Caves are natural laboratories to investigate evolutionary processes in the ocean. In contrast to the many described lineages of cave exclusive crustaceans and annelids, very little is known about cave scalidophorans. We here describe two new species of kinorhynchs from a lava tube in the Canary Islands and a cenote in the Yucatan Peninsula. Leiocanthus bretti sp. nov., from Tenerife, is mainly characterized by the lack of middorsal structure specializations on all trunk segment, middorsal line covered by hairs on segments 3–9, unpaired paradorsal setae on segments 2–9, middorsal seta on segment 10, and laterodorsal setae on segments 2–9 and 11. Pycnophyes kukulkan sp. nov. from Yucatan is defined by the strong denticulation in the tergal anterior margin, as a barbed comb, followed by the autapomorphic presence a pool of depressed and perforated cuticular annuli on the anterior half of the plate. The species is also defined by the combination of the following features: very long lateral terminal spines (LTS/TL above 38%), middorsal elevations on segments 2–9, unpaired paradorsal setae on segments 4, 6, 8, paired laterodorsal setae on segments 2–9, lateroventral setae on segments 2, 4, 6–8, 10 (two pairs on segment 10), ventrolateral setae on segment 5 plus ventrolateral or ventromedial setae on segments 3–8, and ventromedial ones on segment 9. The new species are discussed in reference to the diversity of cave scalidophorans, including possible adaptations to the ecological conditions found in some caves. A checklist with all the records of scalidophorans in caves is provided.

The genus Condyloderes (Kinorhyncha: Cyclorhagida) in the Mediterranean Sea, including the description of two new species with novel characters

Two new species of Kinorhyncha belonging to the genus Condyloderes (Cyclorhagida: Centroderidae) are described herein. The specimens were collected in the Gulf of Castellammare (Tyrrhenian Sea, Sicily, Southern Italy) and off Livorno (Ligurian Sea, Tuscany, Central Italy), respectively. The new taxa represent the first species of Condyloderes described from the Mediterranean basin. Condyloderes agnetis sp. nov. is distinguished from its congeners by bearing cuspidate spines on segment 3 – a character never reported before for Cyclorhagida – in subdorsal position, paradorsally and sublaterally on segment 7, an extremely short midterminal spine, and a combination of cuspidate spines in lateral accessory position on segments 2 and 9, ventrolaterally slightly displaced ventromedially on segment 5, and ventrolaterally on segment 8. Condyloderes clarae sp. nov. is characterized by a combination of cuspidate spines on segments 5, 8, and 9 only, cuspidate spines ventrolaterally on segment 8 and in a lateral accessory position on segment 9, ventromedial appendages on segments 5, 6, and 7 in females. Both species exhibit the recently described type-6 sensory spots. Furthermore, the female morphology and data on the distribution of Condyloderes multispinosus (McIntyre, 1962) within the Mediterranean Sea are reported, along with the record of the co-occurrence of different species of Condyloderes at the same site. We report a certain degree of intraspecific variation of taxonomically diagnostic characters like the presence or absence of cuspidate spines and sensory spots on some segments in C. agnetis sp. nov. and C. multispinosus. The presence of regularly arranged cuticular hairs on most trunk segments and of an acicular spine in lateral accessory position on segment 1, along with the absence of an area of micropapillae on segment 9 in females of C. agnetis sp. nov. and C. clarae sp. nov., unique within the genus, suggest the existence of distinct evolutionary lines within Condyloderes. The discovery of the two new species highlights the potential species richness of a genus considered species-poor until recently. Our findings underscore the importance of promoting further studies even in rather well investigated areas, such as the Mediterranean basin. Beyond the taxonomic and biogeographical interest, the data reported herein provides additional insights for ongoing taxonomic and phylogenetic investigations on the Centroderidae and allies, and on the whole Cyclorhagida.

Effects of Ringer's solution with different concentrations of alcohol on biphasic compound action potentials of frog sciatic nerve trunk

To quantitatively investigate the effects of Ringer's solution with different concentrations of alcohol (1%～80%) on biphasic compound action potentials (AP) from frog sciatic nerve trunk, and their recoveries from alcohol effects. Individual segments of frog sciatic nerve trunk with a length of 6 to 8 cm were prepared. Ringer's solution with different concentrations of alcohol (0%, 1%, 2%, 4%, 8%, 16%, 32%, 48%, 64% and 80%) was applied onto the segment of the trunk between the stimulus and ground electrodes via an agent reservoir which was newly armed in a nerve trunk shielded chamber for 5 minutes. The nerve trunk was respectively electro-stimulated to generate the biphasic compound AP which was recorded using the experimental system of BL-420F. This was followed by 5 times washout plus 5 min administration with Ringer's solution before recovery recording of AP. Compared to normal Ringer's solution, Ringer's solution with alcohol at ≤4% did not have dramatic impacts on the AP amplitude and conduction velocity, while Ringer's solution with alcohol at ≥8% there was significant decrease in these two parameters. Ringer's solution with alcohol at the conentrations of 16%, 32% and ≥48% could prevent a small proportion (30%), a large proportion (90%) and all (100%) of sciatic nerve trunks, respectively, from generating AP. Washout with normal Ringer's solution after alcohol application at the concentration of ≤32%, AP could totally recover to normal status. While alcohol at the concentration of 48%, 64% and 80%, the probabilities to regenerate APs were 90%, 40% and 0%, and the AP amplitudes were decreased to 60%, 36% and 0%, respectively. After washout, AP conduction velocity showed no difference with alcohol at the concentration of ≤8% when compared with that before washout, while it could not be recovered to normal under alcohol at ≥16%. Ringer's solution with different concentrations of alcohol exerts different effects on biphasic compound AP amplitude and conduction velocity. Hopefully, our findings could be helpful for the alcoholic usage and its recovery from alcoholic damage.

Feasibility of quantifying the physical exposure of materials handlers in the workplace with magnetic and inertial measurement units

Handling tasks can expose workers to risk factors. The objective was to describe the feasibility of using magnetic and inertial measurement units (MIMUs) to quantify the physical exposure of materials handlers in the workplace. Full-body kinematics were obtained with MIMUs on 10 handlers gathering products ordered by retailers with a pallet truck. An observer classified the visual difference (VD) of segment orientation between a MIMUs avatar and video recordings in three categories (none, minor and major) for each product transfer. The feet, arms, shoulders and head were considered similar for ≥97% of observations. The trunk segment obtained the most differences with 9% of minor VD and 5% of major VD, which were related to the duration of the magnetic disturbances of the MIMUs. Estimating parameters of the physical exposure of handlers in the workplace is feasible with kinematics and an order list, but visual verification remains important for scientific rigour.Practitioner Summary: The feasibility of measuring physical exposure with magnetic and inertial measurement units was evaluated on materials handlers in the workplace. Visual observation of the postures indicated that most of the data is considered acceptable. Magnetic disturbances can increase the measurement error, so data must be verified to ensure validity.

Neuroanatomy of mud dragons: a comprehensive view of the nervous system in Echinoderes (Kinorhyncha) by confocal laser scanning microscopy.

BackgroundThe Scalidophora (Kinorhyncha, Loricifera and Priapulida) have an important phylogenetic position as early branching ecdysozoans, yet the architecture of their nervous organ systems is notably underinvestigated. Without such information, and in the absence of a stable phylogenetic context, we are inhibited from producing adequate hypotheses about the evolution and diversification of ecdysozoan nervous systems. Here, we utilize confocal laser scanning microscopy to characterize serotonergic, tubulinergic and FMRFamidergic immunoreactivity patterns in a comparative neuroanatomical study with three species of Echinoderes, the most speciose, abundant and diverse genus within Kinorhyncha.ResultsNeuroanatomy in Echinoderes as revealed by acetylated α-tubulin immunoreactivity includes a circumpharyngeal brain and ten neurite bundles in the head region that converge into five longitudinal nerves within the trunk. The ventral nerve cord is ganglionated, emerging from the brain with two connectives that converge in trunk segments 2–3, and diverge again within segment 8. The longitudinal nerves and ventral nerve cord are connected by two transverse neurites in segments 2–9. Differences among species correlate with the number, position and innervation of cuticular structures along the body. Patterns of serotoninergic and FMRFamidergic immunoreactivity correlate with the position of the brain neuropil and the ventral nerve cord. Distinct serotonergic and FMRFamidergic somata are associated with the brain neuropil and specific trunk segments along the ventral nerve cord.ConclusionsNeural architecture is highly conserved across all three species, suggesting that our results reveal a pattern that is common to more than 40% of the species within Kinorhyncha. The nervous system of Echinoderes is segmented along most of the trunk; however, posterior trunk segments exhibit modifications that are likely associated with sensorial, motor or reproductive functions. Although all kinorhynchs show some evidence of an externally segmented trunk, it is unclear whether external segmentation matches internal segmentation of nervous and muscular organ systems across Kinorhyncha, as we observed in Echinoderes. The neuroanatomical data provided in this study not only expand the limited knowledge on kinorhynch nervous systems but also establish a comparative morphological framework within Scalidophora that will support broader inferences about the evolution of neural architecture among the deepest branching lineages of the Ecdysozoa.

Spine and Lower Extremity Kinematics Exhibited During Running by Adolescent Idiopathic Scoliosis Patients With Spinal Fusion

Study DesignCase-controlled design; biomechanics laboratory setting. ObjectiveTo compare the spine and lower extremity kinematics displayed during high-effort running between individuals with spinal fusion surgery for adolescent idiopathic scoliosis (SF-AIS) and healthy controls (CON). Summary of Background DataIndividuals with SF-AIS often return to exercise and sports that include running. However, how these individuals produce the spinal rotations needed during high-effort running and thus compensate for the loss of spinal flexibility is not known. MethodsTen SF-AIS (posterior-approach spinal fusion; postoperative time: 2.0 ± 0.6 years; physically active) and 10 CON individuals, pair-matched for gender, age, mass, height, and level of physical activity participated. SF-AIS individuals ran on a treadmill at a self-selected submaximal speed perceived as “hard” (15/20 on Borg perceived-effort scale), and CON ran at the SF-AIS pair-matched speed. 3D motion capture system was used to generate trunk and pelvis segmental angles (trunk segments = upper trunk [C7–T8], middle trunk [T9–T12], lower trunk [L1–L5]), relative angles (relative angles between the two consecutive trunk segments), and lower extremity joint angles. The group differences between the SF-AIS and CON were assessed using one-way analysis of covariance (with running speed as the covariate) for trunk, lower extremity, and step kinematics. ResultsSF-AIS participants exhibited a significantly greater (6.1° greater) lower trunk and (6.3° greater) pelvis segmental axial rotation compared with CON during running. In addition, SF-AIS participants displayed a 9.2° less ankle plantarflexion during the support phase. There were no significant differences detected for step kinematics. ConclusionPossibly because of relearned compensatory mechanism, individuals with SF-AIS displayed similar patterns of spine, lower extremity, and step kinematics as healthy controls during high-effort running with some exceptions. Level of EvidenceLevel III.

The feasibility of predicting ground reaction forces during running from a trunk accelerometry driven mass-spring-damper model.

BackgroundMonitoring the external ground reaction forces (GRF) acting on the human body during running could help to understand how external loads influence tissue adaptation over time. Although mass-spring-damper (MSD) models have the potential to simulate the complex multi-segmental mechanics of the human body and predict GRF, these models currently require input from measured GRF limiting their application in field settings. Based on the hypothesis that the acceleration of the MSD-model’s upper mass primarily represents the acceleration of the trunk segment, this paper explored the feasibility of using measured trunk accelerometry to estimate the MSD-model parameters required to predict resultant GRF during running.MethodsTwenty male athletes ran at approach speeds between 2–5 m s−1. Resultant trunk accelerometry was used as a surrogate of the MSD-model upper mass acceleration to estimate the MSD-model parameters (ACCparam) required to predict resultant GRF. A purpose-built gradient descent optimisation routine was used where the MSD-model’s upper mass acceleration was fitted to the measured trunk accelerometer signal. Root mean squared errors (RMSE) were calculated to evaluate the accuracy of the trunk accelerometry fitting and GRF predictions. In addition, MSD-model parameters were estimated from fitting measured resultant GRF (GRFparam), to explore the difference between ACCparam and GRFparam.ResultsDespite a good match between the measured trunk accelerometry and the MSD-model’s upper mass acceleration (median RMSE between 0.16 and 0.22 g), poor GRF predictions (median RMSE between 6.68 and 12.77 N kg−1) were observed. In contrast, the MSD-model was able to replicate the measured GRF with high accuracy (median RMSE between 0.45 and 0.59 N kg−1) across running speeds from GRFparam. The ACCparam from measured trunk accelerometry under- or overestimated the GRFparam obtained from measured GRF, and generally demonstrated larger within parameter variations.DiscussionDespite the potential of obtaining a close fit between the MSD-model’s upper mass acceleration and the measured trunk accelerometry, the ACCparam estimated from this process were inadequate to predict resultant GRF waveforms during slow to moderate speed running. We therefore conclude that trunk-mounted accelerometry alone is inappropriate as input for the MSD-model to predict meaningful GRF waveforms. Further investigations are needed to continue to explore the feasibility of using body-worn micro sensor technology to drive simple human body models that would allow practitioners and researchers to estimate and monitor GRF waveforms in field settings.

Head, trunk and pelvic kinematics in the frontal plane in un-mounted horseback riders rocking a balance chair from side-to-side

For efficient rider-horse communication, the rider needs to maintain a balanced position on the horse, allowing independent and controlled movements of the rider’s body segments. The rider’s balance will most likely be negatively affected by postural asymmetries. The aims of this study were to evaluate inter-segmental symmetry of movements of the rider’s pelvis, trunk, and head segments in the frontal plane while rocking a balance chair from side to side and to compare this to the rider’s frontal plane symmetry when walking. Frontal plane rotations (roll) of the pelvis, trunk and head segments and relative translations between the segments were analysed in twenty moderately-skilled riders seated on a balance chair and rocking it from side to side. Three-dimensional kinematic data were collected using motion capture video. Principal component analysis and linear regression were used to evaluate the data. None of the riders displayed a symmetrical right-left pattern of frontal plane rotation and translation in any of their core body segments. The intersegmental pattern of asymmetries varied to a high degree between individuals. The first three principal components explained the majority of between-rider variation in these patterns (89%). A significant relationship was found indicating that during walking, when foot eversion was present on one side, pelvic/trunk roll during rocking the chair was asymmetric and larger to that same side (P=0.02, slope=0.95 in degrees). The inter-individual variation in the rider’s intersegmental strategies when rocking a balance chair was markedly large. However, there was a significant association to the rider’s foot pattern while walking, suggesting consistent intra-individual patterns over multiple situations. Although further studies are needed to confirm associations between the findings in this study and rider asymmetry while riding, riders’ postural control can likely be improved and this may enhance their sport performance.

Local Dynamic Stability of the Locomotion of Lower Extremity Joints and Trunk During Backward Upslope Walking

Backward slope walking was considered as a practical rehabilitation and training skill. However, its gait stability has been hardly studied, resulting in its limited application as a rehabilitation tool. In this study, the effect of walking direction and slope grade were investigated on the local dynamic stability of the motion of lower extremity joints and trunk segment during backward and forward upslope walking (BUW/FUW). The local divergence exponents (λS) of 16 adults were calculated during their BUW and FUW at grades of 0%, 5%, 10%, and 15%. Mean standard deviation over strides (MeanSD) was analyzed as their gait variability. Backward walking showed larger λS for the abduction-adduction and rotational angles of knee and ankle on inclined surface than forward walking, while λS for hip flexion-extension angle at steeper grades was opposite. No grade effect for any joint existed during BUW, while λS increased with the increasing grade during FUW. As to the trunk, walking direction did little impact on λS. Still, significant larger λS for its medial-lateral and vertical motion were found at the steeper grades during both FUW and BUW. Results indicate that during BUW, the backward direction may influence the stability of joint motions, while the trunk stability was challenged by the increasing grades. Therefore, BUW may be a training tool for the stability of both upper and lower body motion during gait.

Parasemnoderes intermedius gen. n., sp. n.—the First Abyssal Representative of the Family Semnoderidae (Kinorhyncha: Cyclorhagida)

A new genus and new species of semnoderid kinorhynchs, Parasemnoderes intermedius gen. nov., sp. nov. collected from the abyssal plane at the south border of the Kuril-Kamchatka Trench at the depth 5348 m is described and illustrated using light and electron microscopy. This new representative of the family Semnoderidae is characterized by the structure of the first trunk segment consisting of externally closed cuticular ring with indistinct intracuticular tergosternal junctions. Cuticular ring of the first trunk segment is with deep and narrow middorsal incision and much broader midventral incision filled by midventral placid. Lateroventral spines aciculate, on trunk segments 3–9. Lateroventral accessory spines are minute, only on trunk segment 5. Laterodorsal spines on trunk segment 10. Parasemnoderes intermedius gen. nov, sp. nov. constitutes the third genus the Semnoderidae described so far (Semnoderes and Sphenoderes) and the first species of this family described from the abyssal depth. The total species number of the family Semnoderidae has been increased up to 6. A key to the species of the family Semnoderidae is proposed.

Características de los troncos de palma aceitera para la crianza de Rhynchophorus palmarum (Coleoptera: Curculionidae) en la Amazonía peruana

Introduction: In the Peruvian Amazon, felled oil palm (Elaeis guineensis Jacq.) trunks are usually burned to prevent the increase of these residues. These trunks are also used for the rearing of Rhynchophorus palmarum (Linnaeus, 1758) Csiki E., 1936 larvae, which locals use as a food source. Objective: To establish the relationship between the characteristics of the cut E. guineensis trunks and the rearing of R. palmarum larvae. Materials and methods: The research was conducted in three districts (San Pedro-Campo Verde, Tahuayo-Neshuya and Maronal-Curimana) of the department of Ucayali, Peru. The correlation between the number of R. palmarum larvae and the length and diameter of the trunk’s central cylinder was analyzed using the Spearman coefficient (rs ). In addition, the soil texture class was determined and the correlation with the number of larvae was established. Results and discussion: The length and diameter of the felled oil palm trunks were different (P < 0.05) in the three sites evaluated. There is no relationship between the number of R. palmarum larvae and the length and diameter of the trunk segments. By contrast, the soil’s clay loam texture is positively correlated with the number of larvae (rs = 1.00, P < 0.01). The number of larvae was higher in the Tahuayo-Neshuya district samples (145.67 ± 39.67; P Conclusion: Characteristics of the oil palm trunk are not associated with the development of R. palmarum.

Description of an ultrasound-guided thoracic paravertebral block technique and the spread of dye in dog cadavers

ObjectivesTo describe an ultrasound-guided thoracic paravertebral block and determine the distribution after injection of two volumes of methylene blue in dog cadavers. Study designProspective experimental cadaveric study. AnimalsTwelve dog cadavers weighing 11 ± 3 kg. MethodsUltrasound-guided injections aimed at the fifth thoracic (T5) paravertebral space were performed in randomized order using 0.1 or 0.3 mL kg–1 dye solution (six dogs for each volume). Anatomic dissections determined dye spread characteristics, including the presence and degree of staining of spinal nerves, and the presence of intercostal and sympathetic trunk spread. Staining of mediastinum, epidural, intrapleural and contralateral thoracic paravertebral space was recorded. ResultsThere was no significant difference in dye distribution between groups. The use of anatomic landmarks resulted in the inaccurate identification of the T5 paravertebral space. The T4, T5 and T6 paravertebral spaces were injected in four, five and three of 12 dogs, respectively. Complete staining of the spinal nerve of the thoracic paravertebral space injected was observed in 11 of 12 dogs, and partial staining in one dog in the low-volume group. Multisegmental distribution was demonstrated with staining of contiguous spinal nerves in one dog in the high-volume group, and multiple segments of intercostal (three dogs) and sympathetic trunk (four dogs) spread in both groups. No mediastinal, epidural, intrapleural or contralateral thoracic paravertebral space staining was observed. Conclusions and clinical relevanceUltrasound-guided injection at the thoracic paravertebral space resulted in staining of the spinal nerve in all dogs. However, T5 paravertebral space was not accurately identified using anatomic landmarks. Dye distribution was not significantly different between the two groups; therefore, the use of the lower-volume and multiple-site injections would be potentially necessary in clinical cases to achieve ipsilateral blockade of the thoracic wall.

Reliability of posturographic measures obtained during instrumental assessment of trunk control using inertial sensors in individuals with spinal cord injury

The seated position is the most frequent and fundamental for patients with Spinal Cord Injury (SCI). There are tests for clinically assessing seated postural control in SCI, most of them rely on distance related parameters. However, clinical assessment of trunk control in SCI is not enough sensitive to detect and/or describe a possible improvement. Hence, there is a need for practical, objective and reliable assessment tools to demonstrate the efficacy of different interventions in clinical practice. Therefore our objective was to establish the reliability of distance related measures obtained from inertial sensors (IMUs) to assess trunk control in SCI subjects. A cross-cutting study was performed where 15 non SCI subjects and 22 SCI subjects who fulfilled inclusion criteria were recruited. After signature of informed consent, there was held a concurrent application of the trunk control test (TCT) and the instrumental assessment (using IMUs attached to head and trunk of subjects) with repeated measures three times of static and dynamic control selected items, in an interleaved and random manner. IMUs 3D orientation was obtained during all time. Distance related parameters on transverse plane were obtained after applying IMUs 3D orientation to a biomechanical model of head and trunk segments. Dimensions were normalized to body segments. One hundred twenty-four distance related measures were calculated. Test-retest reliability was measured by intraclass correlation coefficients (ICC) of items with repeated measures. High reliability (ICC > 0.5) was found on 10 distance related measures in both areas of static and dynamic equilibrium of TCT, measured on both the head and the trunk of SCI and non SCI subjects. It was demonstrated that the IMU usage has high reliability when measuring distance related parameters of static and dynamic control of the trunk.