Presence Of Variations Research Articles

Clinical-applied anatomy of the carpal tunnel regarding mini-invasive carpal tunnel release.

Carpal tunnel release is a widely performed procedure. Despite a high success rate, iatrogenic neurovascular injuries can occur which lead to a painful and unsatisfying outcome. This study conducted a detailed examination of the anatomy of the carpal tunnel and the proximity of neurovascular structures that are particularly susceptible to injury, especially in the context of minimally invasive carpal tunnel release procedures. The anatomy of the carpal tunnel of 104 wrists of 52 body donors was examined. The precise anatomical location and the presence of variations were recorded for the median nerve, ulnar nerve, ulnar artery and Berrettini branch. The distance between the median nerve, the ulnar artery, the ulnar nerve, and the Berrettini branch was measured in a proximo-distal and radio-ulnar direction in relation to the distal ulnar end of the carpal tunnel. The authors identified four main dangerous anatomical situations. (1) A proximal separation of the Long-Finger/Ring-Finger branch of the median nerve together with a narrow safe-zone; (2) an ulnar take-off of the recurrent muscle branch of the median nerve with a close radio-ulnar distance to the distal ulnar end of carpal tunnel; (3) an ulnar arterial arch lying close to the transverse carpal ligament; and (4) a proximal Berrettini branch also lying close to the latter. All situations are illustrated by photographs. Additionally, the authors present a sonographic carpal tunnel assessment protocol in order to reduce the risk of injury of any neurovascular structure in the proximity of the carpal tunnel. Certain patients may inherently face an increased risk of neurovascular injuries during minimally invasive carpal tunnel releases due to their anatomical variations. Four potentially risky scenarios were clearly illustrated. Consequently, one may consider conducting a preoperative ultrasound assessment of neurovascular structures at risk, when endoscopic or ultrasound-guided tunnel release are planned. In high-risk patients, open surgery should be preferred. II.

Implementation of fuzzy logic controller for positive output LUO converter

This paper describes the fuzzy logic controller (FLC) for a positive output LUO converter (POLC), which uses a voltage controller to achieve the output voltage regulation. The fourth-order POLC DC–DC converter produces positive output voltage utilizing the voltage lift technique. Due to the converter’s switching functions and its inherently time-varying nature, it exhibits a highly nonlinear dynamic response. To enhance the dynamic performance of the converter, controllers are designed using small signal model and frequency response analysis. The closed loop is used to evaluate converter performance in the presence of variations in reference voltage, source voltage and load disturbances. The power loss analysis of the converter is performed. The comparative results show that FLC gives good dynamic response for wide range of variations than the proportional–integral (PI) controller. The prototype model is built using dsPIC (30F4011) microcontroller, and the experimental results are presented to validate the simulation results.

Multivariate analysis of morphometric traits of the horse ecotypes reared in highlands of Bale Zone, Ethiopia

This study was conducted to evaluate morphometric traits of horse ecotypes reared in four districts of the Bale highlands, southeastern Ethiopia. Twenty-seven morphometric traits were measured from 500 horses (294 males and 206 females) of both sexes. Data were analyzed using SAS 2012. This study revealed that certain traits, such as head length, loin length, bi-ischial width, and sternum height of horses were similar. However, significant differences (p < 0.0001, p < 0.01, p < 0.05) were observed in other traits across the districts. All traits were affected by age (p < 0.05) except rump width and canon perimeter. All 27 morphometric traits were subjected to STEPDISC analysis, of which 21 had the best discriminating power. The uppermost distances of 32.2 and, 28.8 were reported between the Agarfa and Dinsho and, Agarfa and Sinana horse populations, respectively. Mean separation distance among districts ranges from -1.75 to 3.57, -2.42 to 2.43, and -1.61 to 0.92 for CAN1, CAN2 and CAN3, respectively. The quadratic discriminate function classified 95.2, 94.4, 96.0, and 96.8 % of the sampled horses into source populations of the Dinsho, Agarfa, Sinana, and Goba districts, respectively. In addition, the cross-validation summary revealed reduced consistency of membership among each districts with 5 % average success rates and 4, 8, 4, and 4 % for the Dinsho, Agarfa, Sinana, and Goba districts, respectively. Therefore, the presence of variation in morphometric traits within the Bale Highland horse ecotypes has the potential for selection and further genetic interventions.

Quantification of water exchange across the blood-brain barrier using noncontrast MR fingerprinting.

A method is proposed to quantify cerebral blood volume ( ) and intravascular water residence time ( ) using MR fingerprinting (MRF), applied using a spoiled gradient echo sequence without the need for contrast agent. An in silico study optimized an acquisition protocol to maximize the sensitivity of the measurement to and changes. Its accuracy in the presence of variations in , , and was evaluated. The optimized protocol (scan time of 19 min) was then tested in a exploratory healthy volunteer study (10 volunteers, mean age 24 3, six males) at 3 T with a repeat scan taken after repositioning to allow estimation of repeatability. Simulations show that assuming literature values for and , no variation in , while fitting only and , leads to large errors in quantification of and , regardless of noise levels. However, simulations also show that matching , , , and , simultaneously is feasible at clinically achievable noise levels. Across the healthy volunteers, all parameter quantifications fell within the expected literature range. In addition, the maps show good agreement between hemispheres suggesting physiologically relevant information is being extracted. Expected differences between white and gray matter (p < 0.0001) and (p < 0.0001) are observed, and show no significant differences, p = 0.4 and p = 0.6, respectively. Moderate to excellent repeatability was seen between repeat scans: mean intra-class correlation coefficient of , , , and . We demonstrate that regional simultaneous quantification of , , , and using MRF is feasible in vivo.

Minerals content of water sources for livestock production in Ethiopia

Minerals are essential nutrients for sustainable livestock production and productivity. Water is a source of minerals to livestock production beside of feed minerals. Presence of some minerals in water at higher levels will be toxic to animals and will affect animal health and productivity. So, it is essential to know the mineral content of water sources for livestock consumption in the country. This paper is based on a review of literature that were conducted on the mineral content and quality of water sources mainly for human consumption and other purposes in Ethiopia. Based on the literature values of the mineral content of the water sources and recommended values of minerals in livestock drinking water, the water sources were assessed for their suitability for livestock production. The review showed that the presence of variation in the mineral content of the water sources in Ethiopia. In addition, there is variation in the mineral content of the water sources between the dry and the wet season. The total dissolved solids (TDS), Calcium, magnesium, chromium and zinc content of the water sources in Ethiopia is within acceptable levels for livestock consumption. But the sodium, chloride, copper, fluoride, iron, lead and manganese content of some of the water sources (river, well and lake) in the country is beyond the maximum recommended level. This demands implementation of mitigation mechanisms to reduce the mineral contents of water sources; otherwise, it will result in deleterious effects on the health and productivity of animals. Generally, there is lack of adequate research on the mineral content of water sources for livestock production in the country. So, there is a need to conduct more research on the water sources being consumed by livestock in the country in the future.

Localized corrosion of nitrogen-doped diamond-like carbon films on the surface of 304 stainless steel

Nitrogen-doped diamond-like carbon (N-DLC) films with different nitrogen content were prepared on the surface of 304 stainless steel (SS) using plasma-enhanced chemical vapour deposition technology. Localized failure mechanisms of the N-DLC films under long-term exposure to sodium chloride solutions have been investigated. The results demonstrated that nitrogen doping significantly affected the failure behavior of the N-DLC films. When undoped, the number of pore defects in the film is high, providing a channel for the corrosive medium to attack the substrate metal. Meanwhile, due to the high internal stress within the undoped film, extensive exfoliation of the film occurred under the effect of the growth of oxides at the film-substrate interface. The DLC film on 304 SS is subject to stress corrosion cracking failure during long-term service in sodium chloride solution. However, when nitrogen doping is 10 sccm, the pH of the micro-zone solution was highly variable due to the dissolution of nitrogen in the film and the processes of formation and hydrolysis of NH4+. A large number of residual metal cations dissolved from the substrate combine with oxygen at the corrosion pits mouth to form oxides. This can aggravate the occlusion effect of the pits and severe pitting corrosion of 304 SS occurs under autocatalytic effects. The N-DLC film with 5 sccm nitrogen addition showed the excellent durability properties. The evolution mechanism of oxidation and dissolution behaviors in the presence of variations in local hydrochemistry is also discussed.

How Important Is Variation in Extrinsic Reproductive Isolation to the Process of Speciation?

The strength of reproductive isolation (RI) between two or more lineages during the process of speciation can vary by the ecological conditions. However, most speciation research has been limited to studying how ecologically dependent RI varies among a handful of broadly categorized environments. Very few studies consider the variability of RI and its effects on speciation at finer scales-that is, within each environment due to spatial or temporal environmental heterogeneity. Such variation in RI across time and/or space may inhibit speciation through leaky reproductive barriers or promote speciation by facilitating reinforcement. To investigate this overlooked aspect of speciation research, we conducted a literature review of existing studies of variation in RI in the field and then conducted individual-based simulations to examine how variation in hybrid fitness across time and space affects the degree of gene flow. Our simulations indicate that the presence of variation in hybrid fitness across space and time often leads to an increase in gene flow compared to scenarios where hybrid fitness remains static. This observation can be attributed to the convex relationship between the degree of gene flow and the strength of selection on hybrids. Our simulations also show that the effect of variation in RI on facilitating gene flow is most pronounced when RI, on average, is relatively low. This finding suggests that it could serve as an important mechanism to explain why the completion of speciation is often challenging. While direct empirical evidence documenting variation in extrinsic RI is limited, we contend that it is a prevalent yet underexplored phenomenon. We support this argument by proposing common scenarios in which RI is likely to exhibit variability and thus influence the process of speciation.

Nonlinear control of two-stage single-phase standalone photovoltaic system.

This paper presents a single-phase Photovoltaic (PV) inverter with its superior and robust control in a standalone mode. Initially, modeling and layout of the Buck-Boost DC-DC converter by adopting a non-linear Robust Integral Back-stepping controller (RIBSC) is provided. The controller makes use of a reference voltage generated through the regression plane so that the operating point corresponding to the maximum power point (MPP) could be achieved through the converter under changing climatic conditions. The other main purpose of the Buck-Boost converter is to act like a transformer and produce an increased voltage at the inverter input whenever desired. By not using a transformer makes the circuit size more compact and cost-effective. The proposed RIBSC is applied to an H-bridge inverter with an LC filter to produce the sinusoidal wave in the presence of variations in the output to minimize the difference between the output voltage and the reference voltage. Lyapunov stability criterion has been used to verify the stability and finite-time convergence of the overall system. The overall system is simulated in MATLAB/Simulink to test the system performance with different loads, varying climatic conditions and inverter reference voltages. The proposed methodology is compared with a back-stepping controller and Proportional Integral Derivative (PID) controller under rapidly varying climatic conditions. Results demonstrated that the proposed technique yielded a tracking time of 0.01s, a total harmonic distortion of 9.71% and a root means square error of 0.3998 in the case of resistive load thus showing superior control performance compared to the state-of-the-art control techniques.

Morphological Characterization and Diversity Assessment of Mungbean [Vigna radiata (L.) Wilczek] Genotypes using DUS Descriptors as per PPV and FRA, 2001

Background: Variety characterization is the foremost important step that should be done by breeders to classify a variety into distinct groups. A significant technique for locating and assessing several genotypes for the registration, protection and production of seeds of superior quality is the Distinctness, Uniformity and Stability (DUS) characterization. Consequently, the current investigation aimed to use DUS descriptors to describe and assess the variance present in mungbean genotypes. Methods: One hundred forty-two mungbean genotypes were examined using 21 agro-morphological qualitative DUS descriptors in a randomized block design with two replications across two seasons, kharif 2021 and kharif 2022. Result: In the twenty-one DUS traits that were examined, four characters’ plant growth habit, leaf shape, leaf size and seed size exhibited trimorphic variance. Three characters (plant habit, stem pubescence and pod pubescence) were found to be identical among all genotypes while fourteen characters displayed dimorphic variance. All of the mungbean genotypes displayed a significant degree of variance for all DUS characteristics. Based on the UPGMA method of clustering, the dendrogram classified all the one hundred forty-two genotypes into three major clusters. The presence of variation among the genotypes under study was demonstrated by the further classification of these primary clusters into five sub-clusters. The majority of the genotypes were found in cluster II (121 genotypes), which was followed by cluster I (18 genotypes) and cluster III (3 genotypes).

Linguistic aspects of language culture: study of norms, standards and variations in speech communication

The article examines the linguistic aspects of a language culture. It describes the study of norms, standards and variations in speech communication. The relevance of this study originates from the fact that today, speech communication plays a significant role as intercultural communication intensifies. Hence, people living in the globalized world should be able to use their language to express themselves as a person. At the same time, learning norms and standards is a complex and continuous process. Moreover, the presence of variations in speech communication requires not only theoretical but also practical knowledge of the language culture. This study aims to determine some linguistic aspects of the language culture regarding learning norms, standards and variations in speech communication. The subject of the study is speech communication as an element of the language culture. The following research methods were used in this paper: description, analysis and synthesis, comparison, generalization, and linguistic analysis. The article is devoted to researching linguistic aspects of the language culture in terms of studying norms, standards and variations in speech communication. The authors defined the essence of the "language culture" concept and its main aspects. In particular, the basic linguistic norms of linguistic culture are described. These norms include the rules of quantity, quality, modality, precision, orientation, and word standardization. The article explored the peculiarities of applying linguistic norms. The specificity of using exoticisms, barbarisms, and borrowings in speech was also determined. The authors revealed linguistic standards of the language culture.

Analysis of Micro Structure, Porosity Disability and Wear Resistance with Volume Variation from Riser On the Engine Cover of Electric Motors

This research to analyze the microstructure, porosity defects, and wear resistance of aluminum casting in the presence of variations in the volume of risers. The method used is the pre-experimental method of the One-Shot Case Study type, because in this study a treatment will be carried out and the results will be observed. The treatment that will be carried out is the addition of variations not using risers, variations of riser cylinders with a volume of 2826mm3, variations of riser cylinders with a volume of 4710mm3, variations of riser cylinders with a volume of 6594mm3. Microstructure testing used the Meji Techno IM 7200 test tool. Wear testing used the Ogoshi High Speed Universal Wear Testing Machine (Type OAT-U). The data analysis used is descriptive analysis to provide an overview of the research subject based on data from the variables obtained from the group of subjects studied. The best microstructure is shown by the cast specimens with the riser volume variation of 6594mm3 as evidenced by the formation of a more dense and even structural phase. The best porosity results were shown by the specimens that were cast with a volume variation of the riser 6594mm3 of 37.97%. The best wear resistance results in variations of the volume riser 6594mm3 with wear values of 0.51x10-7mm2/kg.

A combined method based on CNN architecture for variation-resistant facial recognition

Identifying individuals from a facial image is a technique that forms part of computer vision and is used in various fields such as security, digital biometrics, smartphones, and banking. However, it can prove difficult due to the complexity of facial structure and the presence of variations that can affect the results. To overcome this difficulty, in this paper, we propose a combined approach that aims to improve the accuracy and robustness of facial recognition in the presence of variations. To this end, two datasets (ORL and UMIST) are used to train our model. We then began with the image pre-processing phase, which consists in applying a histogram equalization operation to adjust the gray levels over the entire image surface to improve quality and enhance the detection of features in each image. Next, the least important features are eliminated from the images using the Principal Component Analysis (PCA) method. Finally, the pre-processed images are subjected to a neural network architecture (CNN) consisting of multiple convolution layers and fully connected layers. Our simulation results show a high performance of our approach, with accuracy rates of up to 99.50% for the ORL dataset and 100% for the UMIST dataset.

Studies of Genetic Variability and Inter-Relationship among Some Pumpkin (Cucurbita moschata L.) Landrace of Assam, India

Thirty diverse landraces of pumpkin comprising from eight districts of Assam viz., four landraces from each district, Sivasager, Dibrugarh, Karbi Anglong, Haflong, Jorhat &amp; Majuli and three landraces from each Lakhimpur and Kokrajhar. The landraces were subjected to analyses of variance and covariance for estimation of genetic variability parameters and correlation coefficients among the 19 characters. The experiment was carried out during the rabi season of 2017-18 at the Instruction Cum and Research (ICR) Farm of Assam Agricultural University in a Randomized Block Design with three replications. From the analysis of variance, it was recorded that the presence of variation among thirty pumpkin landraces for all characters. The highest genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) was recorded for single fruit weight with 51.47 per cent and 54.88 per cent, indicating presence of greater variability for the trait. The heritability in the broad sense was recorded highest for the petiole length. The GA calculated as per cent of the mean was recorded for single fruit weight (99.44%), followed by yield per plant. In character association five traits were positively correlated with fruit yield per plant out of 18 characters.

Failure mechanisms of nitrogen-doped diamond-like carbon films: Exfoliation or localized attack behaviour of films under hydrochemistry evolution

Nitrogen-doped diamond-like carbon (N-DLC) films with different nitrogen content were prepared on the surface of 2024 aluminium alloy using plasma-enhanced chemical vapour deposition technology. The failure mechanisms of the N-DLC films during seawater exposure have been investigated. The results demonstrated that nitrogen doping significantly affected the failure behaviour of the DLC films in seawater. Extensive exfoliation of the DLC film was found without the addition of nitrogen. However, when the nitrogen flow rate is 10 sccm and 15 sccm, significant localized corrosion of the DLC film and the aluminium alloy substrate occurred. The difference in the thermodynamic process of corrosion of the N-DLC films was mainly due to the changes in pH value on the local solution caused by the formation and hydrolysis of NH4+. In the DLC film without nitrogen additive, large oxide particles were formed at the film-substrate interface due to the acidification of the solution. Meanwhile, the internal stress of the DLC film was high under this condition. The film was easily exfoliated and ultimately lost its protective effect on the substrate. The corrosion products could not grow sustainably due to the variable pH value when excess nitrogen was added to the DLC film. No extensive exfoliation of the DLC films with 10 sccm and 15 sccm nitrogen addition has occurred, but obvious corrosion channels were formed in the substrate because of the localized corrosion. The evolution mechanism of oxidation behaviour in the presence of variations in local hydrochemistry is also discussed.

Endodontic management of Mandibular second premolar with aberrant root and canal morphology: a case report

A proper understanding about variations in root canal anatomy and confounding nature of human pulpal system plays a significant role in success of endodontic treatment. Presence of variations should always be considered even in teeth like mandibular second premolars which show very less frequency of unusual root canal anatomy. The case report presents diagnosis and successful endodontic management of mandibular left second premolar with a very rare and peculiar type of root and canal anatomy (Vertucci type V root canal configuration). Keywords: Aberrant root, Mandibular second premolar, Root canal, Variable canal anatomy.

Response of Hypolimnetic Water and Bottom Sediment Microbial Communities to Freshwater Salinization—A Microcosm Experiment

The introduction of NaCl in freshwater caused by winter runoffs is a problem whose consequences are still little understood. We sought to analyze the effect of NaCl addition on microbial communities of the hypolimnion and bottom sediments of a Canadian lake. Using microcosms comprising a salinity gradient varying between 0.01 and 3.22 ppt (10–3220 mg/L−1) NaCl, we investigated the effect of salinity on prokaryotic absolute abundance and diversity, following a three- and six-week exposure, and detected the presence of a salinity threshold for microbial communities’ differentiation. We observed a significant decline of bacterial diversity after six weeks in hypolimnetic samples. In the sediments, no clear effect of NaCl was observed on abundance or diversity, despite the presence of variations throughout the salinity gradient. The implication of nutrient fluctuations as well as the co-occurrence of species and inter-domain interactions is likely and would strongly contribute to the development of salt-exposed prokaryotic communities. In hypolimnetic water and sediments, the archaeal and eukaryotic communities differed significantly from 0.93 ppt (930 mg/L−1), while only conclusive at 1.9 ppt (1900 mg/L−1) NaCl in bacteria, meaning that the regulations in place are possibly suitable for the protection of the microbial communities in the hypolimnion and sediment lake layers.

FACE IDENTIFICATION USING BACK-PROPAGATION ADAPTIVE MULTIWAVENET

Face Identification is an important research topic in the field of computer vision and pattern recognition and has become a very active research area in recent decades. Recently multiwavelet-based neural networks (multiwavenets) have been used for function approximation and recognition, but to our best knowledge it has not been used for face Identification. This paper presents a novel approach for the Identification of human faces using Back-Propagation Adaptive Multiwavenet. The proposed multiwavenet has a structure similar to a multilayer perceptron (MLP) neural network with three layers, but the activation function of hidden layer is replaced with multiscaling functions. In experiments performed on the ORL face database it achieved a recognition rate of 97.75% in the presence of facial expression, lighting and pose variations. Results are compared with its wavelet-based counterpart where it obtained a recognition rate of 10.4%. The proposed multiwavenet demonstrated very good recognition rate in the presence of variations in facial expression, lighting and pose and outperformed its wavelet-based counterpart.

Inferring the Mean Thickness of the Outer Ice Shell of Enceladus From Diurnal Crustal Deformation

AbstractThe thickness of the outer ice shell plays an important role in several geodynamical processes at ocean worlds. Here, we show that observations of tidally driven diurnal surface displacements can constrain the mean ice shell thickness, . Such estimates are sensitive to any significant structural features that break spherical symmetry such as faults and lateral variation in ice shell thickness and structure. We develop a finite‐element model of Enceladus to calculate diurnal tidal displacements for a range of values in the presence of such structural heterogeneities. Consistent with results from prior studies, we find that the presence of variations in ice shell thickness can significantly amplify deformation in thinned regions. If major faults are also activated by tidal forcing—such as Tiger Stripes on Enceladus—their characteristic surface displacement patterns could easily be measured using modern geodetic methods. Within the family of Enceladus models explored, estimates of that assume spherical symmetry a priori can deviate from the true value by as much as ∼41% when structural heterogeneities are present. Additionally, we show that crustal heterogeneities near the South Pole produce differences of up to 35% between Love numbers evaluated at different spherical harmonic orders. A ∼41% range in estimates of from Love numbers is smaller than that found with approaches relying on static gravity and topography (∼250%) or analyzing diurnal libration amplitudes (∼85%) to infer at Enceladus. As such, we find that analysis of diurnal tidal deformation is a relatively robust approach to inferring mean crustal thickness.

Modified Tracer Gas Injection for Measuring Stream Gas Exchange Velocity in the Presence of Significant Temperature Variation

AbstractGas exchange between streams and overlying air is an important physical‐chemical environmental process that is typically determined by injecting a tracer gas into a stream at a steady rate and sampling steady‐state tracer gas concentrations in the stream water. Previous modes of tracer gas injection allow gas‐water partitioning of the tracer gas, making the rate of gas injection and thus the measured gas transfer velocity potentially sensitive to temperature variation. Presented here is a modification to the tracer solution injection method in which a tracer gas solution was prepared in Tedlar® bags from which all headspace was removed before injecting the solution into the stream. Along with four other strategies to prevent a headspace from forming in the bags during tracer injection in the field, this zero‐headspace tracer solution method prevents gas‐water partitioning anywhere in the injection system, allowing a steady delivery of tracer gas to the stream even in the presence of variation in air and/or stream water temperature. A field test of the method in Nebraska yielded a gas transfer velocity of 4.1 m/day, within the range found in the literature for similarly‐sized streams.

Rapid evolution, rearrangements and whole mitogenome duplication in the Australian stingless bees Tetragonula (Hymenoptera: Apidae): A steppingstone towards understanding mitochondrial function and evolution

The extreme conservation of mitochondrial genomes in metazoans poses a significant challenge to understanding mitogenome evolution. However, the presence of variation in gene order or genome structure, found in a small number of taxa, can provide unique insights into this evolution. Previous work on two stingless bees in the genus Tetragonula (T. carbonaria and T. hockingsi) revealed highly divergent CO1 regions between them and when compared to the bees from the same tribe (Meliponini), indicating rapid evolution. Using mtDNA isolation and Illumina sequencing, we elucidated the mitogenomes of both species. In both species, there has been a duplication of the whole mitogenome to give a total genome size of 30,666 bp in T. carbonaria; and 30,662 bp in T. hockingsi. These duplicated genomes present a circular structure with two identical and mirrored copies of all 13 protein coding genes and 22 tRNAs, with the exception of a few tRNAs that are present as single copies. In addition, the mitogenomes are characterized by rearrangements of two block of genes. We believe that rapid evolution is present in the whole Indo-Malay/Australasian group of Meliponini but is extraordinarily elevated in T. carbonaria and T. hockingsi, probably due to founder effect, low effective population size and the mitogenome duplication. All these features - rapid evolution, rearrangements, and duplication - deviate significantly from the vast majority of the mitogenomes described so far, making the mitogenomes of Tetragonula unique opportunities to address fundamental questions of mitogenome function and evolution.