Left Halves Research Articles

Asymmetric development of the nervous system.

The human nervous system consists of seemingly symmetric left and right halves. However, closer observation of the brain reveals anatomical and functional lateralization. Defects in brain asymmetry correlate with several neurological disorders, yet our understanding of the mechanisms used to establish lateralization in the human central nervous system is extremely limited. Here, we review left-right asymmetries within the nervous system of humans and several model organisms, including rodents, Zebrafish, chickens, Xenopus, Drosophila, and the nematode Caenorhabditis elegans. Comparing and contrasting mechanisms used to develop left-right asymmetry in the nervous system can provide insight into how the human brain is lateralized. Developmental Dynamics 247:124-137, 2018. © 2017 Wiley Periodicals, Inc.

Analysing Anthropometric Measurement and Body Shape Data to Incorporate Body Asymmetry, due to Scoliosis, into Improved Clothing Sizing Systems

The purpose of this research was to improve current clothing sizing systems of female adolescents with adolescent idiopathic scoliosis (AIS). AIS is a complex, three-dimensional spinal deformity, appearing particularly among children aged 8–14 years, especially in girls (nine girls for one boy), resulting in body asymmetry that could affect a female adolescent’s appearance, compromising her health and ability to function. The study took place in Greece where today scoliosis affects at least 2.9% of the population. Measuring procedures were used that were specifically adapted for body asymmetry and that complied with the appropriate code of ethics. Using front/back and left/right arc measurements, both right and left body halves of 75 females aged 16–22 years diagnosed with AIS were measured in order to register their different body shapes and classify them into different scoliotic groups. Analysis of the measurements related to the trunk documented the asymmetry arising from the different types and degrees of spinal curvature that provided a three-dimensional classification of scoliotic deformities, according to the magnitude and type of scoliosis. As a result of this classification, different size charts were created and mathematically evaluated to correspond to different scoliotic groups.

Stereocontrolled Synthesis of Left Halves of Halichondrins.

A stereocontrolled synthesis of the left halves of halichondrins was reported. An intramolecular oxy-Michael reaction under basic conditions was used to construct the [6,6]-spiroketal in a stereocontrolled manner. With this approach, the left halves of halichondrins, homohalichondrins, and norhalichondrins were synthesized.

Unified, Efficient, and Scalable Synthesis of Halichondrins: Zirconium/Nickel-Mediated One-Pot Ketone Synthesis as the Final Coupling Reaction.

Unified, efficient, and scalable syntheses of the halichondrin natural products are reported. A newly developed Zr/Ni-mediated one-pot ketone synthesis was used to couple the two halves of the final product at a late stage in the synthesis. With the use of a slight excess of the left halves, the desired ketones were isolated in yields of 80-90 %. The halichondrins were obtained from these ketones in two steps, namely desilylation and [5,5]-spiroketal formation. The new synthetic route was effective for the total synthesis of all members in the homohalichondrin subgroup. The scalability of this process was demonstrated with halichondrin B; 150 mg of halichondrin B (68 % overall yield) were obtained from 200 mg of the right-half precursor.

Unified, Efficient, and Scalable Synthesis of Halichondrins: Zirconium/Nickel‐Mediated One‐Pot Ketone Synthesis as the Final Coupling Reaction

AbstractUnified, efficient, and scalable syntheses of the halichondrin natural products are reported. A newly developed Zr/Ni‐mediated one‐pot ketone synthesis was used to couple the two halves of the final product at a late stage in the synthesis. With the use of a slight excess of the left halves, the desired ketones were isolated in yields of 80–90 %. The halichondrins were obtained from these ketones in two steps, namely desilylation and [5,5]‐spiroketal formation. The new synthetic route was effective for the total synthesis of all members in the homohalichondrin subgroup. The scalability of this process was demonstrated with halichondrin B; 150 mg of halichondrin B (68 % overall yield) were obtained from 200 mg of the right‐half precursor.

Dynamics of hard rods with initial domain wall state

Inspired by recent results on the non-equilibrium dynamics of many-body quantum systems, we study the classical hard rod problem in one dimension with initial domain wall condition. Hard rods are an integrable system, in the sense that for each velocity the density of particles is locally conserved. It was proven by Boldrighini et al (1983 J. Stat. Phys. 31 577) that on the hydrodynamic space-time scale, the fluid of hard rods satisfies Euler-type equations which comprise all conservation laws. We provide the general solution to these equations on the line, with an initial condition where the left and right halves are, asymptotically, in different states. The solution is interpreted as being composed of a continuum of contact discontinuities, one for each velocity. This is a classical counterpart of the transport problem solved recently in quantum integrable systems. We also discuss the Navier–Stokes (viscous) corrections, and study its effect on the broadening of the contact discontinuity and on entropy production.

Contextual cueing in 3D visual search depends on representations in planar-, not depth-defined space.

Learning of spatial inter-item associations can speed up visual search in everyday life, an effect referred to as contextual cueing (Chun & Jiang, 1998). Whereas previous studies investigated contextual cueing primarily using 2D layouts, the current study examined how 3D depth influences contextual learning in visual search. In two experiments, the search items were presented evenly distributed across front and back planes in an initial training session. In the subsequent test session, the search items were either swapped between the front and back planes (Experiment 1) or between the left and right halves (Experiment 2) of the displays. The results showed that repeated spatial contexts were learned efficiently under 3D viewing conditions, facilitating search in the training sessions, in both experiments. Importantly, contextual cueing remained robust and virtually unaffected following the swap of depth planes in Experiment 1, but it was substantially reduced (to nonsignificant levels) following the left-right side swap in Experiment 2. This result pattern indicates that spatial, but not depth, inter-item variations limit effective contextual guidance. Restated, contextual cueing (even under 3D viewing conditions) is primarily based on 2D inter-item associations, while depth-defined spatial regularities are probably not encoded during contextual learning. Hence, changing the depth relations does not impact the cueing effect.

Compact and high-resolution optical orbital angular momentum sorter

A compact and high-resolution optical orbital angular momentum (OAM) sorter is proposed and demonstrated. The sorter comprises a quadratic fan-out mapper and a dual-phase corrector positioned in the pupil plane and the Fourier plane, respectively. The optical system is greatly simplified compared to previous demonstrations of OAM sorting, and the performance in resolution and efficiency is maintained. A folded configuration is set up using a single reflective spatial light modulator (SLM) to demonstrate the validity of the scheme. The two phase elements are implemented on the left and right halves of the SLM and connected by a right-angle prism. Experimental results demonstrate the high resolution of the compact OAM sorter, and the current limit in efficiency can be overcome by replacing with transmissive SLMs and removing the beam splitters. This novel scheme paves the way for the miniaturization and integration of high-resolution OAM sorters.

Morphological, densitometric and mechanical properties of mandible in 5-month-old Polish Merino sheep.

BackgroundAmong bones building the axial and appendicular skeleton, the mandible is characterized by unique morphological and functional traits. The aim of the study was to evaluate morphological, densitometric and mechanical properties of mandible in 5-month-old Polish Merino sheep. Using quantitative computed tomography, volumetric bone mineral density (vBMD) and calcium hydroxyapatite density of the cortical bone (CbCa-HA), mean vBMD (MvBMD) and total bone volume were determined. Using computed tomography cross-sectional scans of the mandible, cross-sectional area, second moment of inertia, mean relative wall thickness and cortical index were determined. Three-point bending test was applied to determine mechanical properties. Serum concentration of insulin-like growth factor I (IGF-I) and bone-specific alkaline phosphatase (BAP) was also measured.ResultsAll the investigated morphometric, densitometric and mechanical parameters of the right and left mandibular halves were not significantly different (P > 0.05). There was no correlation of final body weight, MvBMD, CbCa-HA, BAP and IGF-I with all the analyzed parameters of mandible (P > 0.05). However, positive correlations between the other investigated morphometric, densitometric and mechanical parameter of mandible were found (P < 0.05).ConclusionsRelationships between morphological, densitometric and mechanical parameters of the mandible indicate that the elaborated experimental model may serve for further studies on metabolic responses of skeletal system to physiological, nutritional, pharmacological, toxicological and environmental factors.

Meniscal regeneration after resection of the anterior half of the medial meniscus in mice.

Various animal studies have indicated that reduced meniscal function significantly exacerbates articular-cartilage degeneration. Despite the importance of meniscal function for joint homeostasis and prevention of osteoarthritis, the healing process after meniscal injury and the regenerative process after meniscus removal have not been studied in detail. In this study, we examined the process of meniscal regeneration and cartilage degeneration after meniscectomy in mice. The left anterior halves of the medial menisci in male C57Bl/6J mice were resected, and histological assessment of the process of meniscal regeneration was conducted on day 3 and 2, 4, and 6 weeks after the surgical procedure. Extensive macrophagic infiltration into the synovial membrane around the meniscectomized area was observed on day 3. Synovial hyperplasia was detected 2 weeks after the operation. At this stage, synovial tissue was filled with many fibroblastic cells, which underwent chondrocytic differentiation and produced cartilage matrices by 4 weeks after the operation. At 6 weeks, regenerated tissues resembled those of an intact meniscus. The articular cartilage at the interface of the resected meniscus significantly degenerated between 2 and 4 weeks after the surgical procedure, but subtle progression in cartilage degeneration was observed between 4 and 6 weeks. This finding is suggestive of a balance between meniscal regeneration and cartilage homeostasis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1958-1965, 2017.

A New Approach of Generating Object Reference Frame for Maxillary Dental Arch

One of the important steps in orthognathic surgical planning is to restore the symmetrical alignment of dental arches with the midsagittal plane (MSP) of the whole face. Analyzing dental arch symmetrical alignment requires an object reference frame: midsagittal plane (MSP) should divide the arch evenly into right and left halves; axial (occlusal) plane should evenly pass through incisal edges and occlusal cusps; and coronal plane is mutually perpendicular to the other two. Unfortunately, there is no effective method of generating such object reference frame. In the past, we developed a triangular method for our computer-aided surgical simulation (CASS). It was straightforward and easy to implement. However, this method was only reliable when a dental arch was relatively symmetrical, the teeth were relatively well aligned, and there was no partial edentulous dentition unilaterally. Therefore, in this study, we developed a new method to mathematically generate an object reference frame for maxillary dental arch, and compared it to other methods.

Convergent evolutionary reduction of atrial septation in lungless salamanders.

Nearly two thirds of the approximately 700 species of living salamanders are lungless. These species respire entirely through the skin and buccopharyngeal mucosa. Lung loss dramatically impacts the configuration of the circulatory system but the effects of evolutionary lung loss on cardiac morphology have long been controversial. For example, there is presumably little need for an atrial septum in lungless salamanders due to the absence of pulmonary veins and the presence of a single source of mixed blood flowing into the heart, but whether lungless salamanders possess an atrial septum and whether the sinoatrial aperture is located in the left or right atrium are unresolved; authors have stated opposing claims since the late 1800s. Here, we use micro‐computed tomography (μ‐CT) imaging, gross dissection and histological reconstruction to compare cardiac morphology among lungless plethodontid salamanders (Plethodontidae), salamanders with lungs, and the convergently lungless species Onychodactylus japonicus (Hynobiidae). Plethodontid salamanders have partial atrial septa and incomplete separation of the atrium into left and right halves. Partial septation is also seen in O. japonicus. Hence, lungless salamanders from two lineages convergently evolved similar morphology of the atrial septum. The partial septum in lungless salamanders can make it appear that the sinoatrial aperture is in the left atrium, but this interpretation is incorrect. Outgroup comparisons demonstrate that the aperture is located in a posterodorsal extension of the right atrium into the left side of the heart. Independent evolutionary losses of the atrial septum may have a similar developmental basis. In mammals, the lungs induce formation of the atrial septum by secreting morphogens to neighboring mesenchyme. We hypothesize that the lungs induce atrial septum development in amphibians in a similar fashion to mammals, and that atrial septum reduction in lungless salamanders is a direct result of lunglessness.

A pilot study of cardiac electrophysiology catheters to map and pace bladder electrical activity.

This is a pilot study to evaluate the feasibility of using diagnostic cardiac electrophysiology catheters for recording intrinsic urinary bladder electrical activity and for electrical pacing capture of bladder tissue. During cystoscopy, a curved quadripolar catheter was introduced and contact was made with the right and left halves of the dome and trigone in adult female patients undergoing cystoscopy. Electrical activity was recorded, using a commercially available cardiac electrophysiologic recording system, before and during pacing at 0.5-3.0 Hz. Apparent spontaneous electrical depolarizations were detected in both the trigone and the dome. The amplitude of these depolarizations was in the microVolt range. During pacing, local electrical capture was noted in the trigone, but not in the dome. Spontaneous low-amplitude electrical activity was detected in the bladder through the use of commercially available cardiac electrophysiology equipment. While these low-level signals could represent noise, the voltage, and morphology resemble detrusor muscle action potentials previously seen in animal studies. Pacing induced local electrical capture in the trigone but not the dome.

Quality Improvement of Pork Loin by Dry Aging.

This study aimed to investigate the effects of dry aging on the quality of pork loin. Longissimus lumborum muscles were dissected from the right half of five pork carcasses and were used as the control samples. The left halves of the carcasses were aged at 2±1℃ and a relative humidity of 80% for 40 d. The total aerobic bacteria count was similar between the control and dry-aged pork loin (p>0.05). Lactic-acid bacteria was absent in both the control and dry-aged pork loins. Dry-aged pork loin contained low moisture and high protein and ash compared to the controls (p<0.05). The pH was higher and cooking loss was lower in dry-aged pork loin compared to that in the control (p<0.05). Flavor related compounds, such as total free amino acid, hypoxanthine, and inosine of pork loin were higher in dry-aged pork loin; whereas, inosine 5'-monophosphate and guanosine 5'-monophosphate were low in dry-aged pork loin than control (p<0.05). There was no difference in carnosine and anserine content between dry-aged pork loin and the control (p>0.05). Dry-aged pork loin had lower hardness and shear force and received higher core in sensory evaluation than the control (p<0.05). According to the results, dry aging improved textural and sensorial quality of pork loin.

Evaluation of staining and color changes of a resin infiltration system.

To analyze the staining and color changes of a resin infiltrant system used for management of white spot lesions (WSLs). WSLs were artificially created on left buccal halves of 48 extracted human teeth. These sites were then treated with resin infiltration (RI) while the right halves of the teeth remained as nonresin (NRI) areas. Six groups were formed (n = 8 teeth/group) and were exposed to the following: red wine, coffee, orange juice, combined staining agents, accelerated aging, and distilled water for 1 week. The teeth were then polished with a prophy cup and polishing paste. Color properties were assessed using a spectrophotometer at baseline (T0), after each exposure (T1), and after polishing (T2). Color difference (ΔE*) was calculated between each time point for both halves of the teeth (RI and NRI). Data were analyzed with a two-way analysis of variance with presence of resin infiltration and staining agents as the main effects for each time point pair. Multiple comparisons were made with a Bonferroni post hoc test. The level of significance was set at P < .05. The red wine and combined staining agent groups caused the greatest color change between all intervals (P < .05). Significant interactions were recorded between resin infiltration application and staining agents at all time periods (P < .05). The presence of resin infiltration as a main effect did not affect color change between T0 and T2 (P > .05). RI areas showed higher staining susceptibility than did NRI areas. However, prophylaxis had a strong effect on reversing the discoloration of both RI and NRI areas.

A GABAergic tecto-tegmento-tectal pathway in pigeons.

Previous studies have demonstrated that the optic tecta of the left and right brain halves reciprocally inhibit each other in birds. In mammals, the superior colliculus receives inhibitory γ-aminobutyric acid (GABA)ergic input from the basal ganglia via both the ipsilateral and the contralateral substantia nigra pars reticulata (SNr). This contralateral SNr projection is important in intertectal inhibition. Because the basal ganglia are evolutionarily conserved, the tectal projections of the SNr may show a similar pattern in birds. Therefore, the SNr could be a relay station in an indirect tecto-tectal pathway constituting the neuronal substrate for the tecto-tectal inhibition. To test this hypothesis, we performed bilateral anterograde and retrograde tectal tracing combined with GABA immunohistochemistry in pigeons. Suprisingly, the SNr has only ipsilateral projections to the optic tectum, and these are non-GABAergic. Inhibitory GABAergic input to the contralateral optic tectum arises instead from a nearby tegmental region that receives input from the ipsilateral optic tectum. Thus, a disynaptic pathway exists that possibly constitutes the anatomical substrate for the inhibitory tecto-tectal interaction. This pathway likely plays an important role in attentional switches between the laterally placed eyes of birds. J. Comp. Neurol. 524:2886-2913, 2016. © 2016 Wiley Periodicals, Inc.

Специфика межличностного восприятия в условиях предъявления целого и «разделенного лица» на примере портретных изображений

&lt;p&gt;The article presents a study of the specificity of perception of expression of the whole and fragmented (divided into left and right half) face made on the example of the perception of pictorial portraits. The data obtained in the study are fully consistent with previously obtained results of the similar study of perception of facsimiles (Artemtseva, 2003, Barabanschikov, Boldyrev, 2007; Barabanschikov, Zhegallo, 2013). The right and the left side of the face and the image of a whole face have their own expressive potential, which is reflected in the use by observer of different individual psychological characteristics in their description. The expression of a whole face often has a contradictory character with overly intensified emotions and is not a simple sum of the characteristics that are used in the description of the right and left halves of the face. Thus, perception of expression of a whole face and of a &amp;ldquo;split face&amp;rdquo; brings up several different patterns of personality. The similarity of the experimental data, obtained at different stimulus material (portraits and images), speaks about the invariance of perception of human face, regardless of the method of its representation.&lt;/p&gt;

Comparative study on carcass characteristics in lambs from the Bulgarian dairy synthetic population and its F1 crosses with Ile de France and Mutton Charolais

The objective of this study was to determine the effects of the father’s breed onto the carcass characteristics in lambs from the Bulgarian Dairy Synthetic Population and its F1 crosses with Ile de France and Mutton Charolais breeds. The scientific study took place at the Sheep Farm with the Agricultural Institute of Stara Zagora, Bulgaria. Object of the study were lambs from the Bulgarian Dairy Synthetic Population and its crosses with Ile de France and Mutton Charolais breeds. After reaching a live weight of 21-24 kg, 9 male lambs of different crosses were slaughtered. Slaughter took place at a licensed slaughter house. The lamb carcasses were chilled for 24 hours. Following this, linear measurements were made on the left carcass halves. The father’s breed has a significant proven effect onto the large and small circumference of the leg (P≤ 0.001) and a proven effect onto the carcass length (P≤ 0.01). The Ile de France crosses feature 17.44% bigger leg circumference in comparison with the animals from the reference group. Similar is the situation with the Mutton Charolais crosses where we have 14.93% bigger leg circumference compared to that in the reference group. Determined is also an effect onto the weight of the chilled carcass and the carcass yield. The lambs from the trial groups have a proven bigger leg weight (P≤ 0.001), proven bigger chilled carcass weight (P≤ 0.01) and they show a trend for proving the effect on the carcass yield (P≤ 0.05).

Application of a LED-photodiode optocouple for the study of human respiratory function

Application of a LED-photodiode optocouple for the study of human respiratory function is considered. The optocouple operating in the middle-infrared part of the spectrum (with the peak of the LED emission at 4.1 μm at 300 K) was applied for monitoring changes in CO2 concentration during respiration of a human. Studies were carried out simultaneously with the measurements of pressure in the left and right halves of the nose cavity. The results of the study open possibilities for using infrared optocouples as sensitive elements in compact and cheap sensors detecting breath abnormalities associated with respiratory and other diseases.

Classification of Brain MRI Images using Computational Intelligent Techniques

MRI of brain can reveal important abnormalities and brain diseases such as brain tumours if these MRI images can be processed properly by intelligent algorithms. As the MRI images have low contrast and contain noise; it is difficult to precisely separate the region of interest between tumour and normal brain tissues. In this paper, computationally intelligent techniques have been presented to classify brain MRI images into normal and abnormal (having tumour) ones. The first method uses Gabor filters to extract the texture features from magnetic resonance brain images and then performs classification between normal and abnormal images using Support Vector Machine (SVM). A second method is also presented which uses novel histogram comparison method of left and right halves of brain based on Bhattacharya coefficient and finds bounding box as region of interest (ROI). Texture features are extracted using Gabor filters from this ROI. Finally the classification of images was performed using Artificial Neural Networks. A comparison of both the proposed methods is given at end.