Variation In Number Research Articles

Cytogenetic Analysis of the Fish Genus Carassius Indicates Divergence, Fission, and Segmental Duplication as Drivers of Tandem Repeat and Microchromosome Evolution.

Fishes of the genus Carassius are useful experimental vertebrate models for the study of evolutionary biology and cytogenetics. Carassius demonstrates diverse biological characteristics, such as variation in ploidy levels and chromosome numbers, and presence of microchromosomes. Those Carassius polyploids with ≥150 chromosomes have microchromosomes, but the origin of microchromosomes, especially in European populations, is unknown. We used cytogenetics to study evolution of tandem repeats (U1 and U2 small nuclear DNAs and H3 histone) and microchromosomes in Carassius from the Czech Republic. We tested the hypotheses whether the number of tandem repeats was affected by polyploidization or divergence between species and what mechanism drives evolution of microchromosomes. Tandem repeats were found in tetraploid and hexaploid Carassius gibelio, and tetraploid Carassius auratus and Carassius carassius in conserved numbers, with the exception of U1 small nuclear DNA in C. auratus. This conservation indicates reduction and/or loss in the number of copies per locus in hexaploids and may have occurred by divergence rather than polyploidization. To study the evolution of microchromosomes, we used the whole microchromosome painting probe from hexaploid C. gibelio and hybridized it to tetraploid and hexaploid C. gibelio, and tetraploid C. auratus and C. carassius. Our results revealed variation in the number of microchromosomes in hexaploids and indicated that the evolution of the Carassius karyotype is governed by macrochromosome fissions followed by segmental duplication in pericentromeric areas. These are potential mechanisms responsible for the presence of microchromosomes in Carassius hexaploids. Differential efficacy of one or both of these mechanisms in different tetraploids could ensure variability in chromosome number in polyploids in general.

Above and belowground phenotypic response to exogenous auxin across Arabidopsis thaliana mutants and natural accessions varies from seedling to reproductive maturity.

Plant hormones influence phenology, development, and function of above and belowground plant structures. In seedlings, auxin influences the initiation and development of lateral roots and root systems. How auxin-related genes influence root initiation at early life stages has been investigated from numerous perspectives. There is a gap in our understanding of how these genes influence root size through the life cycle and in mature plants. Across development, the influence of a particular gene on plant phenotypes is partly regulated by the addition of a poly-A tail to mRNA transcripts via alternative polyadenylation (APA). Auxin related genes have documented variation in APA, with auxin itself contributing to APA site switches. Studies of the influence of exogenous auxin on natural plant accessions and mutants of auxin pathway gene families exhibiting variation in APA are required for a more complete understanding of genotype by development by hormone interactions in whole plant and fitness traits. We studied Arabidopsis thaliana homozygous mutant lines with inserts in auxin-related genes previously identified to exhibit variation in number of APA sites. Our growth chamber experiment included wildtype Col-0 controls, mutant lines, and natural accession phytometers. We applied exogenous auxin through the life cycle. We quantified belowground and aboveground phenotypes in 14 day old, 21 day old seedlings and plants at reproductive maturity. We contrasted root, rosette and flowering phenotypes across wildtype, auxin mutant, and natural accession lines, APA groups, hormone treatments, and life stages using general linear models. The root systems and rosettes of mutant lines in auxin related genes varied in response to auxin applications across life stages and varied between genotypes within life stages. In seedlings, exposure to auxin decreased size, but increased lateral root density, whereas at reproductive maturity, plants displayed greater aboveground mass and total root length. These differences may in part be due to a shift which delayed the reproductive stage when plants were treated with auxin. Root traits of auxin related mutants depended on the number of APA sites of mutant genes and the plant's developmental stage. Mutants with inserts in genes with many APA sites exhibited lower early seedling belowground biomass than those with few APA sites but only when exposed to exogenous auxin. As we observed different responses to exogenous auxin across the life cycle, we advocate for further studies of belowground traits and hormones at reproductive maturity. Studying phenotypic variation of genotypes across life stages and hormone environments will uncover additional shared patterns across traits, assisting efforts to potentially reach breeding targets and enhance our understanding of variation of genotypes in natural systems.

Characterization of the diversity of barn owl's mitochondrial genome reveals high copy number variations in the control region.

Mitochondria are known to play an essential role in the cell. These organelles contain their own DNA, which is divided in a coding and non-coding region (NCR). While much of the NCR's function is unknown, tandem repeats have been observed in several vertebrates, with extreme intra-individual, intraspecific and interspecific variation. Taking advantage of a new complete reference for the mitochondrial genome of the Afro-European Barn Owl (Tyto alba), as well as 172 whole genome-resequencing; we (i) describe the reference mitochondrial genome with a special focus on the repeats in the NCR, (ii) quantify the variation in number of copies between individuals, and (iii) explore the possible factors associated with the variation in the number of repetitions. The reference mitochondrial genome revealed a long (256bp) and a short (80bp) tandem repeat in the NCR region. The re-sequenced genomes showed a great variation in number of copies between individuals, with 4 to 38 copies of the Long and 6 to 135 copies of the short repeat. Among the factors associated with this variation between individuals, the tissue used for extraction was the most significant. The exact mechanisms of the formations of these repeats are still to be discovered and understanding them will help explain the maintenance of the polymorphism in the number of copies, as well as their interactions with the metabolism, the aging and health of the individuals.

Conserved untranslated regions of multipartite viruses: Natural markers of novel viral genomic components and tags of viral evolution.

Viruses with split genomes are classified as being either segmented or multipartite based on whether their genomic segments occur within a single virion or across different virions. Despite variations in number and sequence during evolution, the genomic segments of many viruses are conserved within the untranslated regions (UTRs). In this study, we present a methodology that combines RNA sequencing with iterative BLASTn of UTRs (https://github.com/qq371260/Iterative-blast-v.1.0) to identify new viral genomic segments. Some novel multipartite-like viruses related to the phylum Kitrinoviricota were annotated using sequencing data from field plant samples and public databases. We identified potentially plant-infecting jingmen-related viruses (order Amarillovirales) and jivi-related viruses (order Martellivirales) with at least six genomic components. The number of RNA molecules associated with a genome of the novel viruses in the families Closteroviridae, Kitaviridae, and Virgaviridae within the order Martellivirales reached five. Several of these viruses seem to represent new taxa at the subgenus, genus, and family levels. The diversity of novel genomic components and the multiple duplication of proteins or protein domains within single or multiple genomic components emphasize the evolutionary roles of genetic recombination (horizontal gene transfer), reassortment, and deletion. The relatively conserved UTRs at the genome level might explain the relationships between monopartite and multipartite viruses, as well as how subviral agents such as defective RNAs and satellite viruses can coexist with their helper viruses.

Spatio-temporal usage of water sources by Black-cheeked Lovebirds Agapornis nigrigenis: implications for conservation planning

Summary The Black-cheeked Lovebird Agapornis nigrigenis has a highly restricted range in dry south-western Zambia, where its distribution is clumped and localised in association with mopane Colophospermum mopane woodland and permanent water pools. Fieldwork and monitoring over 30 months between December 2018 and October 2021 established that the lovebirds’ usage of pools for drinking was higher towards the centre of the bird’s distribution and influenced by the pools’ proximity to mopane woodlands, surrounding tree cover, and level of human activity. Of the four pool types available for use by lovebirds (i.e. mopane, grassland, river, and artificial), mopane and grassland pools were disproportionally susceptible to drying out in the dry season, hence showed greater variation in numbers of visiting birds compared with the other two types. Lovebirds showed a preference for pools with a perimeter of <50 m and tended to avoid those with a perimeter >100 m, consistent with a positive association between pool size and human activity. Convergence between humans and lovebirds in dependence on water resources and mopane woodland points to the need to find ways to overcome potential conflicts. Such ways include creating small, shallow-sided, undisturbed pools in or near mopane woodland, extending water retention in existing mopane pools, and enhancing the capacity of artificial pools to meet the needs of the lovebirds.

Short-term Effects of Crude Oil-polluted Soil on the Histomorphometry of the Femoral Cortex

Abstract Introduction: Skeletal remains are crucial in most forensic case investigations. There is therefore need to study the process of bone degradation and distortion caused by environmental factors. The aim of the study is to determine the effect of burial in a crude oil-polluted soil on long bone histomorphometry. Materials and Methods: Fragments of 1-cm diameter sections of the mid-shaft of the femur were obtained from a cadaver and divided into three groups. Group A fragments were not buried (control), Group B fragments were buried in normal clay soil, and Group C fragments were buried in crude oil-polluted soil. The bone fragments were buried for a period of 5 weeks in a crude oil-polluted soil and normal soil of pH 5.30 and 5.75, respectively. Histological sections of the bones were prepared using the modified Frost’s method of bone preparation. Photomicrographs were taken using a Leica ICC50E photomicroscope at four different regions of the slides. An ImageJ software was utilized to analyze the micrographic details. Results: Quantitative analysis showed a reduction in the Haversian canal area (HCA) and Haversian canal diameter (HCD) in the samples of bone fragments buried in the crude oil-polluted soil compared to the control. The crude oil-polluted soil showed a mean HCA and HCD of 83.52 μm and 8.91 μm as against 153.23 μm and 16.01 μm for the control. There was no statistically significant difference (P > 0.05) in HCA and HCD between the control bones and those buried in normal and crude oil-polluted soil. The variation in number of osteons was observed to be nonstatistically significant for both bone samples exposed to crude oil and those not exposed. Conclusion: The result of this study shows that crude oil-polluted soil have little or no effects on bone histomorphometry for a short period of time. This should help guide forensic investigations.

Taxonomic Evaluation of Spinacia oleracea L. Accessions by Morphological and Anatomical Markers

Spinacia oleracea L. is an edible crop and considered as super food due to high nutrient values. Due to these properties the pot-based project was designed to explore the most diverse accession of this species, 31 local S. oleracea accessions were evaluated taxonomically on the basis of morphological and anatomical markers. Seeds were sown in clay pots to evaluate different morphological characters. The germination period varied from 6 to 15 days while variation in number of leaves was observed to be from 12 to 68 leaves per plant. Moreover, abaxial and adaxial epidermal leaf analysis was examined under light microscope to study the existing anatomical variations. Substantial variations were observed among quantitative characters including number of subsidiary cells (3-5 on both abaxial and adaxial sides), stomata number per unit area (6-21 on abaxial side; 8-18 on adaxial side) and stomatal index (13.9-28.6 on abaxial side; 14.8-25.5 on adaxial side). The shape of epidermal cells varied from tetragonal to pentagonal, hexagonal and irregular. The results concluded that leaf epidermal anatomical markers could be applied considerably in delimiting the species to solve the existing taxonomic problems among them. However, for more authentic results it would be preferred to use more taxonomic tools in integration with anatomy to study intraspecific variations.

Times of trouble—seasonal variation in number and severity of attacks on sheep caused by large carnivores and eagles in Sweden

Wildlife managers and livestock owners can choose from a multitude of interventions to prevent carnivore attacks on domestic animals, ranging from light and sound deterrents to fencing and lethal control. To guide management and make the best and most cost-effective choice of interventions, knowledge about where and when these measures are needed the most is important. By identifying spatiotemporal patterns of carnivore attacks, resources can be used more efficiently to prevent such attacks. We used a Swedish nationwide, long-term data set to identify inter- and intra-seasonal variation in probability, number, and severity (number of killed or injured per attack) of large carnivore attacks on sheep. Our results show that there are specific “times of trouble”, regarding the number of attacks from golden eagle (Aquila chrysaetos) in late spring, and from brown bears (Ursus arctos), lynx (Lynx lynx), and wolves (Canis lupus) in late summer. Additionally, for brown bears and wolves, the severity of attacks varied throughout the grazing season with a peak in the latter part of the summer. The results can be used for guidance of temporal prioritisation of preventive interventions to reduce the probability, number, and severity of large carnivore attacks on sheep.

Anatomical Variations and Anomalies of the Middle Cerebral Artery

Intracranial arteries have a high rate of variation, but a clear schematic overview is lacking. In this pictorial review we classify and depict all the variations and anomalies within the middle cerebral artery (MCA). PubMed was searched with the MeSH-term "Middle Cerebral Artery." Articles were selected based on their description of variants within the MCA. Cross-referencing was used to broaden the range of articles. The anatomical variants were then schematically drawn using the anteroposterior and lateral view during angiography of the internal carotid artery. A total of 29 unique medical illustrations were made, depicting variation in number of vessels; variation in vessel origin; and variation in morphology. The MCA provides vital blood supply to the frontal, parietal, temporal, and central brain structures. An overview of these variations is important to diagnose and treat patients with MCA-related pathology correctly and safely. They can aid in distinguishing pathology from normal anatomical variance; aid neurosurgeons during aneurysmal clipping or arteriovenous malformation resections; and aid interventional radiologists during thrombectomy or coiling. This article provides a summary regarding current knowledge of anatomical variations within the MCA, their prevalence and clinical relevance. A total of 29 unique illustrations were made, depicting currently known variants. We encourage all who diagnose, treat, and study the MCA to use this overview for a uniform and better understanding of its anatomy.

Debate 6: Microbiome Testing is Indicated for Implantation Failure in 2023

Motion: For Uninvestigated Recurrent Implantation Failure (RIF) has a significant cost, can waste embryos with the potential for life and leads to empirical therapies such as the use of steroids. Chronic Endometritis (CE) is a known cause of RIF is diagnosed by presence of plasma cells and worsens if steroids suppress the protective immune system response. Identifying plasma cells in endometrial tissue samples requires histological expertise, special staining and there is variation in numbers between tissue sections and microscope fields. Furthermore, culturing bacteria from low biomass environments like the endometrium is difficult and will not identify anaerobes and other fastidious organisms. The molecular technique of sequencing the 16S ribosome enables the identification of microbes that can create a hostile environment for embryos. There is clear evidence that some microbes and microbiome signatures are associated with RIF and that changing the microbiome is associated with higher implantation rates. There are established and emerging treatments for an aberrant microbiome that include antibiotic therapy, probiotics, faecal transplantation, and curettage. The more diagnostic information we can obtain to determine the cause of our patients RIF and then design specific, targeted treatments that are effective, the better their pregnancy outcomes will be. It is useful to test the microbiome and will only become more useful as this technology improves. Motion: Against The microbiome is closely related to women’s reproductive health, and therefore microbiome testing is becoming increasingly important in the field of reproductive medicine, especially in guiding assisted reproduction treatments such as infertility. The human microbiome is a collection of all microorganisms that exist on or within human tissues and fluids, as well as the corresponding anatomical sites where they are located, including the female reproductive tract, gastrointestinal tract, skin, semen, saliva, oral mucous membranes, etc., of which the ones that are most relevant to the study of female infertility mainly include the female reproductive tract flora and gastrointestinal tract flora. Several studies have shown that the composition of the microbiota in the female reproductive tract may affect embryo implantation and pregnancy success. An imbalanced or dysbiased microbiome of the female reproductive tract flora may lead to inflammation, altered immune responses, and hinder the optimal conditions needed for successful embryo implantation. Microbiome Testing can be accomplished through a variety of technologies, such as next-generation sequencing, which allows for a comprehensive analysis of microbial composition. Thus, microbiome testing that involves analyzing the microbial community in the female reproductive tract for imbalance or dysbiosis is a breakthrough point with great potential to aid in the treatment of recurrent implantation failure. For recurrent implantation failures, microbiome testing can help fertility specialists tailor a personalized treatment plan. By understanding an individual’s specific microbial profile, physicians can make informed decisions about potential interventions such as antibiotic therapy, probiotics, or other microbial modulation therapies. Of course, the use of microbiome testing should be carefully considered on a case-by-case basis and should be used in conjunction with other diagnostic tools and assessments to provide optimal treatment for patients with implantation failure.

Seismic Performance Assessment of RCC Building with Podium

With the advancements in structural engineering, seismic performance of buildings can be adjudged on the basis of performance-based techniques. This paper presents the performance based seismic evaluation of buildings with podiums for varying ratios of tower area to podium area. The structural system of the building consists of shear walls and moment resisting frames. Buildings with podiums have been designed and analysed with and without connection between the tower portion and the podium portion for Seismic Zone IV, by carrying out response spectrum analysis as per IS 1893-2016. The structural responses have been compared in terms of diaphragm forces, base shear, time period, storey stiffness, storey shear, storey displacement etc. for the variations in number of podiums i.e., single, double & three podium levels. Performance-based seismic evaluation of the buildings has been carried out with podium and tower as a connected unit with varying ratios of 0.35, 0.45, and 0.55 of tower area to podium area i.e., by keeping the tower area constant and increasing the podium extents. Pushover analysis is carried out and comparison is done for the influence of podium on the non-linear behaviour of the structures.

Habitat Utilization and Feeding Pattern of Avifauna in Goalpara College Campus, Goalpara, Assam, India

A study on habitat utilization and feeding pattern of avian diversity was carried out in Goalpara College campus of Goalpara district, Assam. A total of 44 species of birds belonging to 30 families were recorded and studied. Based on food type eaten, the birds were categorized into seven categories. Variation in number of species based on food type was tested and variation was found insignificant (p=2.22). However, insectivorous category was found to be dominating over other categories. The habitat selection of avian fauna of the campus was also analyzed, and the habitat type H-1 was found to be species rich (38.6%, 17 species) and H-4 type as species-poor habitat (13.6%, 6 species). The order of habitats in terms of species richness is H-1(38.6%, 17 species) > H-3 (27.3%, 12 species) > H-2 (20.5%, 9 species) > H-4 (13.6%, 6 species). The Shannon index for the recorded species showed highest diversity in the habitat type H-1 (H’=1.053) and least diversity in habitat type H-4 (H’=0.577). The study indicates that the college campus provide a suitable habitat for the birds species providing food materials, water, shelters, roosting, and nesting sites. Since birds play a vital role in the ecosystem as pollinators, seed dispersers and help in regeneration of flowering plants and thereby reforestation, therefore an attempt has been made to determine the avian diversity of the college campus with special reference to their habitat utilization and feeding pattern. This study highlights the role of modified habitats to maintain the urban biodiversity. This study will provide base line information on avifauna of Goalpara town which could be useful for management of their habitats.

Cytological studies reveal high variation in ascospore number and shape and conidia produced directly from ascospores in Morchella galilaea.

Spores are important as dispersal and survival propagules in fungi. In this study we investigated the variation in number, shape, size and germination mode of ascospores in Morchella galilaea, the only species of the genus Morchella known to fruit in the autumn. Based on the observation of five samples, we first discovered significant variation in the shape and size of ascospores in Morchella. One to sixteen ascospores were found in the asci. Ascospore size correlated negatively with ascospore number, but positively with ascus size, and ascus size was positively correlated with ascospore number. We noted that ascospores, both from fresh collections and dried specimens, germinated terminally or laterally either by extended germ tubes, or via the production of conidia that were formed directly from ascospores at one, two or multiple sites. The direct formation of conidia from ascospores takes place within asci or after ascospores are discharged. Using laser confocal microscopy, we recorded the number of nuclei in ascospores and in conidia produced from ascospores. In most ascospores of M. galilaea, several nuclei were observed, as is typical of species of Morchella. However, nuclear number varied from zero to around 20 in this species, and larger ascospores harbored more nuclei. One to six nuclei were present in the conidia. Nuclear migration from ascospores to conidia was observed. Conidia forming directly from ascospores has been observed in few species of Pezizomycetes; this is the first report of the phenomenon in Morchella species. Morphological and molecular data show that conidial formation from ascospores is not found in all the specimens of this species and, hence, is not an informative taxonomic character in M. galilaea. Our data suggest that conidia produced from ascospores and successive mitosis within the ascus may contribute to asci with more than eight spores. The absence of mitosis and/or nuclear degeneration, as well as cytokinesis defect, likely results in asci with fewer than eight ascospores. This study provides new insights into the poorly understood life cycle of Morchella species and more broadly improves knowledge of conidia formation and reproductive strategies in Pezizomycetes.

Cardiac coronary tomography angiography (CCTA) use across geographical regions in the USA and the UK: a cross-sectional study

ObjectiveIncreased use of CT imaging has been identified as a key component of unsustainable rising healthcare costs in the USA and globally. Understanding evidence and its relation to imaging coverage...

Controlling coherent perfect absorption via long-range connectivity of defects in three-dimensional zero-index media

Abstract Coherent perfect absorption (CPA), as time-reversed lasing, arises from appropriate wave interference within absorbers, offering flexible control over wave absorption. Typically, this control involves tuning the phase difference between two counter-propagating incident beams. Here, we elucidate the critical role of defect connectivity within three-dimensional zero-index media for realizing and controlling CPA. Specifically, the realization of CPA critically depends on the establishment of long-range connectivity of defects in a specific direction. Once the long-range connectivity is established, the CPA exhibits remarkable resilience against defects’ deformation, changes in size and shape of the zero-index media, as well as variations in number and orientation of incident channels. Notably, a minor disruption to this connectivity will result in a complete reduction of absorption to zero, highlighting an ultra-sensitive absorption property in response to connectivity perturbations. Our findings not only unveil a physical mechanism for realizing CPA but also open up promising avenues for advanced CPA control with versatile functionalities.

A decade of hibernating bat communities along the periphery of a region of white‐nose syndrome

AbstractLong‐term monitoring programs are necessary to assess populations for conservation planning and management decisions. Hibernating bats in North America have declined because of numerous natural and human‐induced disturbances. White‐nose syndrome (WNS) has become the most serious threat to North American cave‐dwelling bats, leading to significant population declines in several species. We examined trends in hibernating bat populations at 11 hibernacula in northern Georgia and Alabama, USA, from 2013–2022, beginning when WNS was first detected in the region. Although we observed interannual variation in numbers of the federally endangered gray bat (Myotis grisescens), mean counts remained stable over time. In contrast, the tricolored bat (Perimyotis subflavus) and the federally endangered northern long‐eared bat (M. septentrionalis) declined by >90% in the first 5 years after WNS detection in the region. Although no northern long‐eared bats have been reported since 2019, tricolored bat counts stabilized following initial declines. Understanding changes in bat populations as WNS continues to spread, and determining the extent of population declines, is necessary for making appropriate management decisions. Our findings elucidate the status of cave‐dwelling bat species along the periphery of the white‐nose syndrome endemic region and highlight the importance of monitoring bat communities on a regional scale to develop effective conservation strategies.

Tidal Variations of Fish Larvae Measured Using a 15-Day Continuous Ichthyoplankton Survey in Subei Shoal: Management Implications for the Red-Crowned Crane (Grus japonensis) Population in Yancheng Nature Reserve.

The National Yancheng Rare Birds Nature Reserve is a vitally important staging habitat for the wild population of red-crowned cranes (Grus japonensis) in China. The population relies on local high-protein food sources, such as fish juveniles, to fuel their migratory journeys. However, little is known about the ecology of the fish larvae and juveniles that migrate to the inshore area via tidal rhythm in Subei Shoal, which is adjacent to the reserve. Therefore, we used a fixed study station (32°55'1.2″ N, 121°19'58.8″ E) to conduct a continuous 15-day ichthyoplankton survey at 2 h intervals beginning at 05:00 on 25 April and ending at 03:00 on 10 May 2019. We identified the tidal variations in the number of fish larvae and juveniles and the number at various developmental stages and assessed how they were related to environmental variables such as sea surface temperature, salinity, turbidity, and tidal height in the Dafeng Sea area of Subei Shoal. We found that the number of species and larval individuals were highest and lowest, respectively, at the highest and lowest tidal height, and they obviously increased and decreased with the rising and ebb tide, respectively. Our findings indicate that the variation in numbers of the larvae and juveniles depends on species and developmental stage. The species Acanthogobius ommaturus, Pholis fangi, Cynoglossus joyneri, Liza haematocheila, and Lateolabrax japonicus and the total number of larvae were most influenced by tidal height. These results provide a better understanding of the habitat of prey species of the red-crowned crane wild population as well as scientific data that can be applied to manage the wild population in the reserve sustainably.

The Arterial Risk Posed by the Posterolateral Approach to the Ankle: An Anatomical Cadaveric Observational Study

Category: Ankle; Trauma Introduction/Purpose: The most commonly used approach for posterior malleolar access is the posterolateral approach. This approach gives good access to the fibula and lateral aspect of the posterior tibia, however; there is little known on the vascular risks with this approach. Methods: The aim of this study was to assess and describe the anatomy of the peroneal artery and its branches at the ankle region. Methodology: Eleven cadaveric foot and ankle specimens were dissected in layers, preserving the peroneal artery, anterior tibial artery (ATA) and posterior tibial artery (PTA). Results: The peroneal artery was consistently found between the peroneal compartment and deep muscular compartment of the posterior leg. A wide range of anatomical variation was found in the peroneal artery, in its location, muscular branches, anastomosis and anterior perforating branch. The peroneal artery was the largest diameter artery in one specimen. There was great variation in number and location of muscular branches. The mean proximal distance between the medial malleolus and the posterior communicating branch of the peroneal artery was 37.93mm (range: 19.03- 85.43mm). The mean proximal distance from the medial malleolus to the anterior peroneal perforating artery was 44.23mm (range:35.44-62.32mm). Distal to the anterior perforating branch of the peroneal artery, the peroneal artery was immobile. Conclusion: Understanding the common variations within the ankle’s arterial anatomy can help surgeons protect these vessels from damage during the surgical approach. The posterolateral surgical approach, specifically puts the peroneal artery at risk and knowledge of its anatomy and variability is important when undertaking this approach.

Anatomical Variations of Flexor Muscles in Sole

Variations in the intrinsic muscles of sole are relatively uncommon. There are 18 intrinsic and 4 extrinsic tendons in the sole of foot. These muscles are subjected to variations which are usually encountered during surgery or cadaveric dissections. During routine cadaveric dissection we came across a combination of variations in sole dissection. There was variation in number of flexor digitorum brevis and variation in the origin of flexor digitorum accessorius. The intertendinous connection between flexor digitorum longus and flexor hallucis longus was also observed. The flexor digitorum brevis muscle, in particular its fourth slip, has a significant clinical and surgical importance in medical practice. The knowledge of the frequency of flexor digitorum brevis fourth slip agenesis and variations in relation to the demographic characteristics of patients is of importance for tendon repair, tendon transfer or soft tissue reconstruction in foot surgery. The exact anatomical knowledge of crossing of Flexor Digitorum Longus and Flexor Hallucis Longus in the foot is essential to facilitate tendon harvesting with less morbidity and explain possible reasons for postoperative functional loss. The understanding of variations of sole muscle is very useful to orthopedic surgeons, radiologists and podiatrists for analyzing foot function and for biomechanical modeling of the foot.

Magnetic resonance angiography in assessment of anomalies of anterior cerebral artery in adults.

Anomalies of anterior cerebral artery (ACA) include aplasia, hypoplasia and variations in number. Magnetic resonance angiography (MRA) is a non-invasive diagnostic technique for assessment of anomalies of cerebral arteries. The aim of the study was to determine the role of MRA in detection of variants of ACA in adults. This study is an observational retrospective study. This study included forty-nine adult cases (28 males and 21 females), mean age 48±12.9 SD with anomalies of ACA in MRA. Magnetic resonance imaging of the brain and MRA were done to all patients. Cerebral MRA and magnetic resonance images were evaluated for frequency and distribution of variants of anterior cerebral arteries, associated aneurysms and infarctions. Odds ratios (ORs) and relative risk were calculated to determine risk of occurrence of cerebral infarctions in patients with anomalies of ACA. Hypoplasia of ACA was the commonest anomaly of ACA (51% of cases). Risk of occurrence of cerebral infarctions was higher in cases with azygos variant (OR, 3.3; P=0.35) than in those with hypoplastic ACA (OR, 2; P=0.58). MRA was highly reliable in identification of different variants of ACA and concomitant vascular changes.