Looping Pattern Research Articles

Assessment of the Anterior Loop and Pattern of Entry of Mental Nerve Into the Mental Foramen: A Radiographic Study of Panoramic Images.

The precise location of the mental foramina is an essential landmark in planning the position of dental implants in the anterior mandible. Injury to inferior alveolar nerve during anterior mandibular implant surgery causes altered sensation which greatly affects patient satisfaction. In this study, we assessed the prevalence of anterior loop of mental nerve and the pattern of entry of mental nerve into the mental foramen. Three hundred panoramic radiographs (600 hemimandibles) obtained from records maintained in the Department of Oral Medicine and Radiology were randomly selected for the study. The radiographs were evaluated by two independent observers for the pattern of entry of mental nerve into the mental foramen on either side of the mandible and for the presence or absence of anterior loop of mental nerve. The most prevalent pattern of mental nerve observed was Straight pattern which totals to 67.5% followed by Anterior loop pattern (18.8%) and then the Perpendicular pattern (13.7%). There was no significant association between the gender and subtypes of looping pattern on the left and right side and a highly significant association between the side of the mandible and loop pattern was observed by Chi square test. The Anterior loop pattern of mental nerve has been found in 18.8% of the population suggesting to accurate planning with three-dimensional imaging techniques to avoid injury to mental nerve during dental implant placement and other surgical procedure involving the interforaminal region of the mandible.

AOIO: Application Oriented I/O Optimization for Buffer Management

Emerging scale-out I/O intensive applications are broadly used now, which process a large amount of data in buffer/cache for reorganization or analysis and their performances are greatly affected by the speed of the I/O system. Efficient management scheme of the limited kernel buffer plays a key role in improving I/O system performance, such as caching hinted data for reuse in future, prefetching hinted data, and expelling data not to be accessed again from a buffer, which are called proactive mechanisms in buffer management. However, most of the existing buffer management schemes cannot identify data reference regularities (i.e., sequential or looping patterns) that can benefit proactive mechanisms, and they also cannot perform in the application level for managing specified applications. In this paper, we present an A pplication Oriented I/O Optimization (AOIO) technique automatically benefiting the kernel buffer/cache by exploring the I/O regularities of applications based on program counter technique. In our design, the input/output data and the looping pattern are in strict symmetry. According to AOIO, each application can provide more appropriate predictions to operating system which achieve significantly better accuracy than other buffer management schemes. The trace-driven simulation experiment results show that the hit ratios are improved by an average of 25.9% and the execution times are reduced by as much as 20.2% compared to other schemes for the workloads we used.

Reynolds stress anisotropy in flow over two-dimensional rigid dunes

Characteristics of turbulence anisotropy in flow over two-dimensional rigid dunes are analysed. The Reynolds stress anisotropy is envisaged from the perspective of the stress ellipsoid shape. The spatial evolutions of the anisotropic invariant map (AIM), anisotropic invariant function, eigenvalues of the scaled Reynolds stress tensor and eccentricities of the stress ellipsoid are investigated at various streamwise distances along the vertical. The data plots reveal that the oblate spheroid axisymmetric turbulence appears near the top of the crest, whereas the prolate spheroid axisymmetric turbulence dominates near the free surface. At the dune trough, the axisymmetric contraction to the oblate spheroid diminishes, as the vertical distance below the crest increases. At the reattachment point and one-third of the stoss-side, the oblate spheroid axisymmetric turbulence formed below the crest appears to be more contracted, as the vertical distance increases. The AIMs suggest that the turbulence anisotropy up to edge of the boundary layer follows a looping pattern. As the streamwise distance increases, the turbulence anisotropy at the edge of the boundary layer approaches the plane-strain limit up to two-thirds of the stoss-side, intersecting the plane-strain limit at the top of the crest and thereafter moving towards the oblate spheroid axisymmetric turbulence.

It's in the loop: shared sub-surface foot kinematics in birds and other dinosaurs shed light on a new dimension of fossil track diversity.

The feet of ground-dwelling birds retain many features of their dinosaurian ancestry. Experiments with living species offer insights into the complex interplay among anatomy, kinematics and substrate during the formation of Mesozoic footprints. However, a key aspect of the track-making process, sub-surface foot movement, is hindered by substrate opacity. Here, we use biplanar X-rays to image guineafowl walking through radiolucent substrates of different consistency (solid, dry granular, firm to semi-liquid muds). Despite substantial kinematic variation, the foot consistently moves in a looping pattern below ground. As the foot sinks and then withdraws, the claws of the three main toes create entry and exit paths in different locations. Sampling these paths at incremental horizons captures two-dimensional features just as fossil tracks do, allowing depth-based zones to be characterized by the presence and relative position of digit impressions. Examination of deep, penetrative tracks from the Early Jurassic confirms that bipeds had an equivalent looping response to soft substrates approximately 200 Ma. Our integration of extant and extinct evidence demonstrates the influence of substrate properties on sinking depth and sub-surface foot motion, both of which are significant sources of track variation in the fossil record of dinosaurs.

Three‐Dimensional Currents in Saturn's Magnetosphere

AbstractObservations of Saturn's magnetic field from July 2004 to December 2016 have been combined to allow a numerical calculation of ∇ × B throughout the magnetosphere, thus permitting the first global mapping of Saturn's currents in three dimensions. The azimuthal ring current Jϕ dominates the magnetospheric currents, peaking near the orbit of the moon Rhea and having a total magnitude of over 10 mega‐Amperes integrated within the L‐shell of Titan. In meridional cross section, the ring current has a teardrop shape rather than a block shape. Jϕ also has a noticeable local time asymmetry, being the largest in the midnight and dawn sectors. The meridional currents Jρ and Jz are smaller than the ring current by an order of magnitude; they flow radially outward near the equator and return at higher latitudes in a looping pattern reminiscent of Hadley cell atmospheric convection. There are two such loops: one in the northern hemisphere and one in the south, flowing in opposing directions. In the noon sector, a strong Jz current may indicate the dayside cusp.

Difference in real-time magnetic image analysis of colonic looping patterns between males and females undergoing diagnostic colonoscopy.

Abstract Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy. Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator. Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern. Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha-loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands.

Innate turning preference of leaf-cutting ants in the absence of external orientation cues

Most ants use a combination of cues for orientation but how do ants find their way when all external cues are suppressed? Do they walk in a random way or are their movements spatially oriented? Here, we show for the first time that leaf-cutting ants (Acromyrmex lundii) have an innate preference for turning counter-clockwise (left) when external cues are precluded. We demonstrated this by allowing individual ants to run freely on the water surface of a newly developed treadmill. The surface tension supported medium-sized workers but effectively prevented ants from reaching the wall of the vessel, which was important to avoid wall-following behaviour (thigmotaxis). Most ants ran for minutes on the spot but also slowly turned counter-clockwise in the absence of visual cues. Reconstructing the effective path walked revealed a looping pattern which could be interpreted as a search strategy. A similar turning bias was shown for groups of ants in a symmetrical Y-maze where twice as many ants chose the left branch in the absence of optical cues. Wall-following behaviour was tested by inserting a coiled tube before the Y-fork. When ants traversed a left-coiled tube, more ants chose the left box and vice versa. Adding visual cues in the form of vertical black strips either outside the treadmill or on one branch of the Y-maze led to oriented walks towards the strips. It is suggested that both turning bias and wall following are employed as search strategies for an unknown environment which can be overridden by visual cues.

Videodermoscopy and doppler-ultrasound in spider naevi: towards a new classification?

Spider naevi (SN) are considered a subtype of telangiectasias, currently classified as low-flow vascular malformations. To describe the videodermoscopy and Doppler-ultrasound (US) features of a large group of SN. A retrospective study of cases of SN collected at our Dermatology department during the period between June 2015 and June 2017 was performed. Clinical images, dermoscopic, videodermoscopic and Doppler-US files were reviewed. For each case, the age of the patient, time since onset, size and dermoscopic pattern of the lesions were recorded. The presence of pulsatility was also evaluated visually on the videodermoscopy. Two hundred and thirty-three SN in 189 patients were included. The mean age was 39.5years (range: 10-76years). Mean size of the lesions was 4.1±2.0mm. We described three dermoscopic patterns: network, star and looping. Older age, longer time since onset and larger size were found associated with higher frequency of the looping and star patterns compared to that of network pattern (P<0.01). Pulsatility during videodermoscopy was found in 88 patients (37%). This pulsatility phenomenon was more commonly associated with the looping pattern (64.7%) than star- (40.3%) or network-like patterns (29.9%) (P<0.001). In Doppler-US studies, a high-flow with arterial biphasic waveform was found. In the light of the results, we support that SN could be reconsidered in upcoming classifications as lesions closer to the group of high-flow arteriovenous malformations.

Near and far effects on gene expression.

Genetic Variation The genes in the human β-globin cluster are co-regulated by a single control region or master cis-regulatory site. Surprisingly, few other master regulators have been identified, although they are suspected to be important in disease. In the past, variants in master regulatory sites have been used to identify defects in the expression of single genes. Tong et al. have expanded the reach of such studies to identify and investigate the effect of variants on the co-regulation of multiple genes. Further analysis of the three-dimensional structure of the genome showed that chromatin looping brings the master regulators adjacent to the genes that they appear to affect. The looping pattern seems to be broadly conserved among mammals. Variation in such regulatory hubs has multiple downstream effects on both genes and noncoding regions that may have shaped genome evolution and complex disease associations. PLOS Genet. 10.1371/journal.pgen.1006673 (2017).

Short-term stable isotopic composition variations of near-surface atmospheric water vapor in four semiarid areas (Binxian, Guyuan, Wujiachuan, Yuzhong) in interior northwestern China

This study used an in situ method to monitor short-term atmospheric water vapor concentrations and stable isotopic composition (δ18Ov and δDv) variations at four sites in semiarid areas of northwestern China during 2014. On a spatial scale, we distinguish a south-to-north difference in atmospheric water vapor concentration. The spatial patterns of water vapor lines (WVLs) may be associated with regional setting. Smaller slopes of WVLs in Guyuan and Yuzhong may reflect dew evaporation, and a steeper slope of WVL in Wujiachuan may be representative of atmospheric water vapor isotopic composition in equilibrium with that of precipitation. On a temporal scale, δ18Ov, δDv, and dv exhibited variable patterns, indicating various influences of entrainment, local evapotranspiration (ET), and dew evaporation. A deceasing trend of atmospheric water vapor δ18Ov and δDv in Wujiachuan indicates that the entrainment effect surpassed that of evaporation; an increasing trend in Guyuan and Yuzhong may be attributed to the effect of evaporation surpassing that of entrainment. Based on a precipitation event at Guyuan, the lateral air mass transported from Wujiachuan may be the reason for rapid recovery of atmospheric vapor isotopic composition to the baseline value and a looping pattern between atmospheric water vapor mixing ratio (w) and δ18Ov observed at Guyuan. Linear correlation coefficients of δ18Ov with w varied from 0.02 to 0.88 at four study sites. Location differences may be the reason for the capability of w to explain why the variability of atmospheric water vapor isotopic composition was greater at Wujiachuan than at Binxian. Dew evaporation after the precipitation event may be the major reason for eliminating the relationship between w and δ18Ov at Guyuan and Yuzhong. Although synoptic conditions were similar at the four sites, δv variations may be controlled by ET, entrainment, and dew formation at different sites and times.

Three Paintings by El Greco

If Sánchez Coello’s approach is essentially decorative, suggesting luxury, El Greco’s version of the court convention is restless and unbalanced, implying a forceful personality. The cardinal sits still but tensely, his drapery swept to the right, which together with the dense shadow beneath the chair suggests slight levitation. The difference between his hands (which evoke Van Dyck and Grünewald) is complemented by the forms around them, with the rectilinear section suggesting stability and the brocade agitation, as if the cardinal held within himself a holy rage. The looping pattern on the wall amplifies the thrust of his glance and the impulsive movement sensed in his left arm.50 He looks to his left, with lips slightly parted, as if reacting to some intrusion (like a Saint Anthony, who has dealt with demons before), or to impart orders, perhaps in response to the unfolded letter on the floor. At least one scholar has seen the hands as suggesting rigid implacability as opposed to the possibility of pardon.51 The accuracy of these speculations is immaterial compared to the fact that El Greco’s characterization of the sitter gives rise to them. Cardinal Niño de Guevara seems to embody the Last Judgment or the Inquisition, if not in action then in resolve.

Inhibition of G9a Methyltransferase in Adult Human Erythroblasts Stimulates Fetal Hemoglobin Production By Facilitating Looping Between LCR and γ-Globin Gene

Globin gene expression undergoes developmental switching from embryonic (ε) through fetal (γ) to adult (δ and β) genes. Inherited mutations or deletions at the β-gene cause beta-thalassemia. One of the most propitious strategies of treatment for the disease is forced switching from mutated β-gene to unaffected fetal γ-gene expression in adult erythroid cells. Expression of globin genes is regulated by the upstream LCR enhancer. The LCR enhancer loops to globin gene promoters utilizing the LDB1/GATA-1/TAL1/LMO2 protein complex. Additionally histone-modifying enzymes play a significant role in regulation of globin gene expression. G9a methyltransferase, responsible for establishing H3K9me2 histone modification, is involved in repressing fetal and activating adult globin gene expression in mouse erythroid cells. Moreover, inhibition of G9a methyltransferase activity by the synthetic chemical compound UNC0638 activates γ- and represses β-gene expression in adult human hematopoietic precursor CD34(+) cells. Using ex vivo differentiation of primary CD34(+) adult human cells as a model system, we investigated the effect of UNC0638 on switching from β- to γ-globin gene expression, LDB1 complex occupancy and LCR/β-gene promoter looping patterns in adult erythroblast cells.Human peripheral blood CD34(+) progenitor cells from three healthy adult donors were differentiated for 21 days in a three phase serum-free media system. Based upon dose titration studies, 1µM UNC0638 was added to the medium during the most proliferative phase of culture (days 7-14) and compared to control cells grown without UNC0638. Under these conditions, a highly significant 5-fold increase in γ-globin gene expression was observed. UNC0638 treatment also caused a pronounced (3-fold) reduction in β-globin gene expression without substantial change in α-globin. At the end of the culture period, HPLC analyses also demonstrated that UNC0638 treatment resulted in a considerable increase in the cellular fetal hemoglobin (HbF / HbA + HbF: control: 2.9 +/- 1.2%; UNC0638: 30.9 +/- 2.5%, p=0.003).Chromatin immunoprecipitation and chromosome conformation capture assays were utilized to determine if the increase of fetal hemoglobin along with activation of γ-gene expression and concomitant reduction of β-gene expression were associated with epigenetic modification of the β-globin locus. UNC0638 erased H3K9me2 histone modification in the β-globin locus and caused changes in LCR looping from interaction with the β- to the γ-globin gene. Mirroring differences in looping pattern, LDB1 containing protein complex occupancy was significantly increased at the γ-globin gene and decreased at δ- and β-gene promoters.These results support a model whereby G9a establishes conditions preventing activation of γ-gene by interacting with the LCR and facilitating LCR looping with δ- and β-gene promoters and subsequent strong activation of adult globin genes expression during differentiation of adult erythroid progenitor cells. In this view, G9a inhibition represents a promising approach for treatment of β-hemoglobinopathies. DisclosuresNo relevant conflicts of interest to declare.

MED1 mediates androgen receptor splice variant induced gene expression in the absence of ligand.

The appearance of constitutively active androgen receptor splice variants (AR-Vs) has been proposed as one of the causes of castration-resistant prostate cancer (CRPC). However, the underlying mechanism of AR-Vs in CRPC transcriptional regulation has not been defined. A distinct transcriptome enriched with cell cycle genes, e.g. UBE2C, has been associated with AR-Vs, which indicates the possibility of an altered transcriptional mechanism when compared to full-length wild-type AR (ARfl). Importantly, a recent study reported the critical role of p-MED1 in enhancing UBE2C expression through a locus looping pattern, which only occurs in CRPC but not in androgen-dependent prostate cancer (ADPC). To investigate the potential correlation between AR-V and MED1, in the present study we performed protein co-immunoprecipitation, chromatin immunoprecipitation, and cell proliferation assays and found that MED1 is necessary for ARv567es induced UBE2C up-regulation and subsequent prostate cancer cell growth. Furthermore, p-MED1 is bound to ARv567es independent of full-length AR; p-MED1 has higher recruitment to UBE2C promoter and enhancer regions in the presence of ARv567es. Our data indicate that p-MED1 serves as a key mediator in ARv567es induced gene expression and suggests a mechanism by which AR-Vs promote the development and progression of CRPC.

Least Recently Used Page Replacement using Last Use Distance (LRUL)

Virtual memory technique is used in modern OS which permits the execution of a program while it is partially available in memory thus providing an illusion of very large memory to the user and freeing the user from the concern of large program size. This uses a page replacement technique such as first in first out (FIFO), least recently used (LRU), optimal etc. to replace a page in memory when a frame is needed and no free frame is available in memory. Here page replacement policy severely affects the performance of virtual memory. It has been observed that LRU approximates optimal so LRU and its variants are quite common in use in operating system as a reasonable choice of page replacement algorithm. But LRU performs very poor by generating continuous page faults while accessing looping pattern if all the pages does not fit in the memory simultaneously. This paper presents a simple modified LRU algorithm called LRUL overcoming this problem using the concept of last use distance (LUD). It is observed that the new algorithm gives better results than LRU. General Terms Operating system, page replacement algorithm.

English

Introduction The course and location of ansa cervicalis of the neck often vary. Because of its closeness with the major vessels and nerves of the neck, any variation in its pattern is of great clinical and surgical importance. This paper reports a case of an unusual looping pattern of ansa cervicalis. Case report We report here an unusual looping pattern of ansa cervicalis. The inferior root of ansa cervicalis, instead of joining the superior root as a single nerve, had both the C2 and C3 components of it joined to the superior root separately without uniting each other. Due to this, two loops of AC were formed superior and inferior. Conclusion Since the branches of ansa cervicalis are often chosen for nerve–muscle transplantation in the treatment of paralysed larynx, and some of the branches arise from the loop of the AC, an abnormal looping pattern may hinder such surgical procedures. Therefore, it is essential to the surgeons to be familiar with its unusual variations.

A Biomechanical Study of Patterning During Gut Development

In order to efficiently pack the lengthy small intestine into the body cavity, the developing vertebrate gut tube forms a reproducible looped pattern as it grows. We previously determined that gut looping morphogenesis is driven by the forces that arise from the differential growth between the gut tube and the anchoring dorsal mesenteric sheet. While the looping pattern provides an artful mechanism for fitting a longer tube into the body, undoubtedly contributing to the luminal surface area necessary for optimal nutrient absorption, one can imagine alternative mechanisms of increasing surface area such as modifying the morphology of the luminal tissue. The lumen of the intestine is covered with finger‐like projections termed villi which serve to dramatically increase the surface area of the intestine. Although very little is known about the mechanism driving villi morphogenesis, the formation of villi has previously been explored at a descriptive level in chick. During this process in chick, the intestine undergoes multiple phases of morphogenesis, beginning with the formation of longitudinally oriented ridges, which appear as an inward buckling of the luminal surface of the tube. These ridges become kinked with regular and uniform periodicity appearing as raised zigzags. These zigzags then enlarge and flatten at which point definitive villi become visible in a specific, predetermined pattern along the zigzags. We hypothesize that tissue‐level forces from the smooth muscle layers lead to these striking patterns seen in the compressed mesenchyme and attached endoderm. These same forces appear to instigate patterns of signaling necessary for outgrowth of definitive villi from the zigzag pattern. Additionally, these signaling environments delineated by tissue‐level forces may be essential for directing the location of adult intestinal stem cell markers during the morphogenesis of villi and crypts.

Variant anatomy of coronary arteries

Introduction: Wide variations exist in the size, position, and shape of various body organs, finger prints, and proteins in different individuals. Some variations are of considerable clinical importance, such as the coronary arteries. Variations of coronary arteries can cause important clinical manifestation, including sudden death of the individual. Materials and Methods: Coronary arteries were dissected in 10% formalin-fixed cadaveric hearts. The normal and variant anatomy of coronary arteries was studied. Result: In 100% of cases, the right coronary artery (RCA) and main left coronary artery (LCA) were found to arise from anterior aortic sinus and left posterior aortic sinus, respectively. In 8% of cases, the conus was found to have independent origin from the anterior aortic sinus. The RCA was found to be dominant in 90% of cases. In 66.7% of cases, the length of RCA ranged from 4.5 cm to 7 cm. The average length of LCA was found to be 7 mm. In 10% of cases, the circumflex coronary artery was found to be dominant, where the length of the artery ranged 9-11 cm. In 10% of cases, LCA trifurcated, where the obtuse marginal branch was replaced by the ramus intermedius branch. Also, 43.3% of LAD showed myocardial bridging predominantly in the middle 1/3 rd segment, and 6.7% of cases of RCA showed myocardial looping. Discussion: Coronary arteries show immense variation in their origin, termination, branching pattern, myocardial bridging, looping, and dominance pattern. This knowledge is clinically and surgically important to manage coronary artery diseases.

Cardiac specific ATP-sensitive K+ channel (KATP) overexpression results in embryonic lethality

Transgenic mice overexpressing SUR1 and gain of function Kir6.2[∆N30, K185Q] KATP channel subunits, under cardiac α-myosin heavy chain (αMHC) promoter control, demonstrate arrhythmia susceptibility and premature death. Pregnant mice, crossed to carry double transgenic progeny, which harbor high levels of both overexpressed subunits, exhibit the most extreme phenotype and do not deliver any double transgenic pups. To explore the fetal lethality and embryonic phenotype that result from KATP overexpression, wild type (WT) and KATP overexpressing embryonic cardiomyocytes were isolated, cultured and voltage-clamped using whole cell and excised patch clamp techniques. Whole mount embryonic imaging, Hematoxylin and Eosin (H&E) and α smooth muscle actin (αSMA) immunostaining were used to assess anatomy, histology and cardiac development in KATP overexpressing and WT embryos. Double transgenic embryos developed in utero heart failure and 100% embryonic lethality by 11.5days post conception (dpc). KATP currents were detectable in both WT and KATP-overexpressing embryonic cardiomyocytes, starting at early stages of cardiac development (9.5dpc). In contrast to adult cardiomyocytes, WT and KATP-overexpressing embryonic cardiomyocytes exhibit basal and spontaneous KATP current, implying that these channels may be open and active under physiological conditions. At 9.5dpc, live double transgenic embryos demonstrated normal looping pattern, although all cardiac structures were collapsed, probably representing failed, non-contractile chambers. In conclusion, KATP channels are present and active in embryonic myocytes, and overexpression causes in utero heart failure and results in embryonic lethality. These results suggest that the KATP channel may have an important physiological role during early cardiac development.

Relationship between the deep peroneal nerve and dorsalis pedis artery in the foot: A cadaveric study

The aim of our work was to study the relationship between deep peroneal nerve (DPN) and dorsalis pedis artery (DPA) so that the frequency of these variations can be kept in mind by the angiographers and surgeons to ensure safe surgical approach during flap surgery. Ninety-two legs in 46 cadavers were dissected to study the relationship between DPN and DPA on the dorsum of the foot. The relationship of neurovascular bundle of the dorsum of the foot was classified into four types. Type I: division of the DPN distal to the midpoint between the two malleoli (observed in 26 limbs). In Type II, the division of the DPN was midway between the two malleoli (seen in 20 limbs). Both Type I and II are further divided into two subtypes (a and b) depending upon the crossing pattern of terminal branches of the DPN over DPA. In Type III, multiple branches of DPN were noted in two limbs. In Type IV, the looping pattern of DPN around the DPA was considered and was seen in eight limbs. Awareness of possible variations in the relationship of the DPA to DPN on the dorsum of the foot is important for vascular and reconstructive surgeons. Because it might help in decreasing confusion when considering treatment options like microvascular anastomosis in reconstruction of the leg.

Complex sexual courtship displays by luminescent male marine ostracods

In the western Caribbean Sea, about an hour after the sun sets, a complex and ritualized light show of precise, vertically placed luminescent pulses erupts over shallow grassbeds. These are among the most complex displays known in marine systems. Displays consist of repeated trains of secreted bioluminescent pulses in a specific pattern ejected into the water column as courtship signals by male Vargula annecohenae, which are small (<2 mm) myodocopid ostracod crustaceans. Although these animals display in near darkness, we have used image intensification and infrared videography and three-dimensional analysis in the lab to demonstrate that each luminescent display train, which can be up to 60 cm long, consists of two distinct luminescent and swimming phases. The first, or 'stationary,' phase consists of three (usually) bright, longer pulses placed close together, with the male swimming in a looping pattern. We hypothesize that this pattern acts as an attention-grabbing signal for receptive females. The stationary phase is followed by the 'helical phase,' which consists of about a dozen evenly placed dimmer, shorter pulses secreted by an individual male rapidly spiraling upward in a helical pattern. We hypothesize that this phase, which has very uniform interpulse intervals and distances, helps an approaching female target and intercept the rapidly moving male. Here we provide details of these two phases, and produce a three-dimensional model of a multiply-displaying male.