Relevant Structures Research Articles

A Cadaver Study: The Relationship of Vital Organs of the Thoracolumbar Junction During a far Lateral Approach Using a T-12 Corpectomy Model.

Human cadaver study. To provide a qualitative and quantitative evaluation by demonstrating measurements of the proximity of vital structures involved and assessed injuries during a T12-corpectomy and cage implantation via a far lateral approach. Six fresh-frozen adult cadaveric specimens were dissected according to standardized protocol. A formal left-sided far lateral T12-corpectomy was carried out by trained experienced spine fellows. Upon completion of the procedure, a cage was placed between T11 and L1. We then turned the patient supine and performed a formal celiotomy and sternotomy to allow for an open anterior central inspection of all structures concerned. Vital structures as in vessels, diaphragm, pleural membranes, neural elements, important foramina of the diaphragm (Bochdalek, Morgagni) and the thoracic duct were identified. Any injuries to these structures were recorded and proximity to key relevant structures to this exposure were measured. We were able to quantify the actual diaphragm excursions and describe its origins to the spine. There was no actual diaphragm injury in any of the cadavers and there were no injuries to the neurovascular structures. We found expected parietal but no visceral pleural injuries. Our cadaver study identified the feasibility of performing a T12-corpectomy through a far lateral approach with no violation of the actual diaphragm and expected limited injuries to the parietal pleura only.

Nickel-Catalyzed O-Arylation of N-Protected Amino Alcohols with (Hetero)aryl Chlorides.

The aryloxyamine motif is a prominent pharmacophore in drug design and development. While these biologically relevant structures could in principle be sustainably assembled from the base metal-catalyzed O-arylation of inexpensive and abundant amino alcohols with (hetero)aryl chlorides, reports of such challenging C-O bond formations with useful scope are lacking. In response, we report herein the hitherto unknown Ni-catalyzed C-O cross-coupling of N-protected amino alcohols (primary, secondary, and tertiary) with (hetero)aryl chlorides. Also presented are chemoselective sequential/telescoped C-N and C-O cross-couplings of the unprotected amino alcohol prolinol to afford an unsymmetrical diarylated product.

Lower Eyelid Surgical Anatomy and the Implications for Blepharoplasty Surgery: A Systematic Review of Anatomic Studies in the Literature.

Lower eyelid blepharoplasty is a procedure to address issues arising from age-related anatomic changes of the lower eyelid. These include excess skin, fat herniation, tear trough hollowing, and midface descent. Unlike the well-defined structures of the upper eyelid, the lower eyelid's anatomy, including the retractors and surrounding ligaments, is less distinct and understudied. In addition, lower eyelid blepharoplasty has an unfavorable complication profile compared with that of the upper eyelid. This review examines relevant studies on lower eyelid anatomy, focusing on age-related structural changes and the variability of key structures involved in blepharoplasty surgery to minimize the risk of complications and achieve desirable outcomes. A literature search for relevant publications on the topic was performed through Medline and PubMed, with the appropriate data extracted, identifying 54 relevant studies. These studies demonstrate how degenerative changes to the supporting structures of the lower eyelid contribute to prolapse of the orbital fat pads, and highlight the relevant ligamentous structures, blood supply, and innervation to avoid complications during transcutaneous or transconjunctival orbital fat repositioning. With detailed knowledge of the anatomy of the lower eyelid as outlined in our review, surgeons can improve and optimize outcomes whilst minimizing complications.

A pre-biblical version of the Cain and Abel story: A subtle condemnation of a dysfunctional social structure

This article argues that, in its pre-biblical version (pre-J), the Cain and Abel story principally dealt with tensions unique to dry-farming families. According to pre-J, the main cause of these tensions was the relevant social structure. The social structure was problematic because it involved two important imbalances, one between the spouses and one between the children. Pre-J offers a novel solution to problems caused by these interfamilial imbalances: rather than accepting their pre-established social roles, people should develop a merit-based social structure. This is why Yahweh says that acceptance and honour are to be found in doing what is right. Focusing on a pre-J narrative in this way and situating the story within the broader context of sibling rivalry solves three puzzles relating to: Yahweh’s preference (God challenges unjust social institutions), Cain’s reactions (he is angry because his expectations were unmet and depressed because he thought that this was his failure), and Yahweh’s final forgiving of Cain (the conflict was not due to Cain’s wicked character).

Definition of reproductive structures in Eucalyptus for phenological data collection.

In an era where global climate change is shifting plant phenology, global meta-analyses of multiple species are required more than ever. Common language or references for enhanced data compatibility are key for such analyses. Although the Plant Phenology Ontology (PPO) addresses this challenge, it does not capture several relevant reproductive structures that are critical in species with long reproductive cycles, like many Eucalyptus species. We reviewed the terminology and concepts that describe reproductive structures in eucalypts and compared them with the existing classes of the PPO to explore the PPO's potential for harmonizing disparate eucalypt datasets. We identified incongruencies within and between eucalypt terminology and the PPO. We tested the sensitivity of the PPO for capturing key eucalypt phenological structures and found it sensitive to classification of certain structures. To address these limitations, we developed the Eucalyptus Phenology Ontology (EPO), a new ontology that builds on the PPO and captures key reproductive structures using a more refined classification. The EPO integrates the relationships between reproductive structures, phenological stages, and phenological traits. The vocabulary is species-neutral so it can be applied to other taxa but specifies the synonyms and descriptions required to capture the complexity of eucalypt phenology.

Fire-Induced Multiple Changes in Electron Transfer Properties of Peat Soil Organic Matter: The Role of Functional Groups, Graphitic Carbon, and Iron.

Peatland fires induced changes in electron transfer properties and relevant electroactive structures of peat soil organic matter (PSOM) remain ambiguous, impeding comprehension of postfire biogeochemical processes. Here, we revealed temperature-dependent electron exchange capacity (EEC) of PSOM dynamics through simulated peat soil burning (150-500 °C), which extremely changed postfire microbial Fe-nanoparticles reduction and methanogenesis. EEC diminished significantly (60-75% loss) due to phenolic-quinone moieties depletion with increasing temperature, regardless of oxygen availability. The final EEC in oxic burning surpassed that of anoxic burning by 1.5 times, attributed to additional quinones from oxygen incorporation. Notably, EEC exhibited heat resistance up to 200 °C and stabilized above 350 °C. Additionally, fire reshaped the EEC-relevant redox-active moieties. Heterocyclic-N generated from burning predominantly contributed to the electron-accepting capacity (EAC) alongside quinones, while phenolic moieties and bonded Fe(II) enhanced the electron-donating capacity (EDC). However, the preferential binding of heterocyclic-N to Fe(II) restricted the EDC of Fe(II). Interestingly, the decrease in EAC declined its electron-shuttling effects in microbial Fe nanoparticle reduction, but fire-induced graphitic carbon formation increased the electrical conductivity (EC) of PSOM, promoting electron transfer. Further, enhanced EC may facilitate methanogenesis in postfire peatlands. These findings advance our understanding of elemental biogeochemical cycles and greenhouse emission mechanisms in postfire peatlands.

Global Optimization of Molybdenum Subnanoclusters on Graphene: A Consistent Approach toward Catalytic Applications.

The development of novel subnanometer clusters (SNCs) catalysts with superior catalytic performance depends on the precise control of clusters' atomistic sizes, shapes, and accurate deposition onto surfaces. The intrinsic complexity of the adsorption process complicates the ability to achieve an atomistic understanding of the most relevant structure-reactivity relationships hampering the rational design of novel catalytic materials. In most cases, existing computational approaches rely on just a few structures to draw conclusions on clusters' reactivity thereby neglecting the complexity of the existing energy landscapes thus leading to insufficient sampling and, most likely, unreliable predictions. Moreover, modeling of the actual experimental procedure that is responsible for the deposition of SNCs on surfaces is often not done even though in some cases this procedure may enhance the significance of certain (e.g., metastable) adsorption geometries. This study proposes a novel systematic approach that utilizes global search techniques, specifically, the particle swarm optimization (PSO) method, in conjunction with ab initio calculations, to simulate all stages in the beam experiments, from predicting the most relevant SNCs structures in the beam and on a surface, to their reactivity. To illustrate the main steps of our approach, we consider the deposition of Molybdenum SNC of 6 Mo atoms on a free-standing graphene surface, as well as their catalytic properties with respect to the CO molecule dissociation reaction. Even though our calculations are not exhaustive and serve only to produce an illustration of the method, they are still able to provide insight into the complicated energy landscape of Mo SNCs on graphene demonstrating the catalytic activity of Mo SNCs and the importance of performing statistical sampling of available configurations. This study establishes a reliable procedure for performing theoretical rational design predictions.

RNA adapts its flexibility to efficiently fold and resist unfolding.

Recent studies have demonstrated that the mechanisms through which biopolymers like RNA interconvert between multiple folded structures are critical for their cellular functions. A major obstacle to elucidating these mechanisms is the lack of experimental approaches that can resolve these interconversions between functionally relevant biomolecular structures. Here, we dissect the complete set of structural rearrangements executed by an ultra-stable RNA, the UUCG stem-loop, at the single-molecule level using a nano-electronic device with microsecond time resolution. We show that the stem-loop samples at least four conformations along two folding pathways leading to two distinct folded structures, only one of which has been previously observed. By modulating its flexibility, the stem-loop can adaptively select between these pathways, enabling it to both fold rapidly and resist unfolding. This paradigm of stabilization through compensatory changes in flexibility broadens our understanding of stable RNA structures and is expected to serve as a general strategy employed by all biopolymers.

Evaluation of a novel forward-looking optical coherence tomography probe for endoscopic applications: an ex vivo feasibility study.

As a result of recent advances in the development of small microelectromechanical system mirrors, a novel forward-looking optical coherence tomography (OCT) probe with a uniquely large field of view is being commercially developed. The aim of this study is to prospectively assess the feasibility of this advanced OCT probe in interpreting ex vivo images of colorectal polyp tissue and to identify necessary steps for further development. A total of 13 colorectal lesions from 9 patients, removed during endoscopic resection, were imaged ex vivo with the OCT device and compared with histopathological images that served as the gold standard for diagnostics. Normal tissue from one patient, removed during the endoscopic procedure, was imaged as a negative control. We assessed the presence of features indicative for polyp type and degree of dysplasia, by comparing OCT images to histopathological images and by evaluating the presence of OCT-specific features identified by previous studies, such as effacement (loss of layered tissue structure), a hyperreflective epithelial layer, and irregularity of the surface. As verified by corresponding histological images, tissue structures such as blood vessels and tissue layers could be distinguished in OCT images of the normal tissue sample. Detailed structures on histological images such as crypts and cell nuclei could not be identified in the OCT images. However, we did identify OCT features specific for colorectal lesions, such as effacement and a hyperreflective epithelial layer. In general, the imaging depth was about 1mm. Some relevant tissue structures could be observed in OCT images of the novel device. However, some adaptations, such as increasing imaging depth using a laser with a longer central wavelength, are required to improve its clinical value for the imaging of colorectal lesions.

Conformal bootstrap equations from the embedding space operator product expansion

We describe how to implement the conformal bootstrap program in the context of the embedding space OPE formalism introduced in previous work. To take maximal advantage of the known properties of the scalar conformal blocks for symmetric-traceless exchange, we construct tensorial generalizations of the three-point and four-point scalar conformal blocks that have many nice properties. Further, we present a special basis of tensor structures for three-point correlation functions endowed with the remarkable simplifying property that it does not mix under permutations of the external quasi-primary operators. We find that in this approach, we can write the M-point conformal bootstrap equations explicitly in terms of the standard position space cross-ratios without the need to project back to position space, thus effectively deriving all conformal bootstrap equations directly from the embedding space. Finally, we lay out an algorithm for generating the conformal bootstrap equations in this formalism. Collectively, the tensorial generalizations, the new basis of tensor structures, as well as the procedure for deriving the conformal bootstrap equations lead to four-point bootstrap equations for quasi-primary operators in arbitrary Lorentz representations expressed as linear combinations of the standard scalar conformal blocks for spin-ℓ exchange, with finite ℓ-independent terms. Moreover, the OPE coefficients in these equations conveniently feature trivial symmetry properties. The only inputs necessary are the relevant projection operators and tensor structures, which are all fixed by group theory. To illustrate the procedure, we present one nontrivial example involving scalars S and vectors V, namely ⟨SSSV⟩.

Prospects of electricity generation through the use of alternative sources such as waste tires processing products

The object of this study is a hybrid energy system that integrates the processes of recycling used tires with the use of alternative energy sources to design a sustainable and environmentally safe power generation system. The problem addressed in this study is to find effective methods for recycling waste tires for electricity generation, as traditional recycling methods are energy-intensive and lead to the loss of valuable resources. Three methods of tire processing have been considered: pyrolysis, thermal degradation, and mechanical grinding. The method of electricity generation using pyrolysis has demonstrated high environmental performance due to a significant reduction in greenhouse gas emissions and a high rate of renewable energy (80 %). According to the results of the study, the use of 5 MW pyrolysis furnaces in combination with 500 kW solar panels provides a reduction in dependence on fossil sources, reducing CO2 emissions to 50.0 kg/year. The method has high capital costs (NPC USD 4.2 million), but the cost of energy production (COE USD 0.18/kWh) makes this method competitive in the long run. Thermal degradation provides a balanced approach in terms of energy efficiency (75 %) and environmental performance. Although its CO2 emissions are higher than in pyrolysis, the method makes it possible to obtain additional products that could be used in other industries, thereby increasing economic efficiency. Mechanical shredding has the lowest average energy costs (USD 0.12/kWh) and the lowest CO2 emissions (30.0 kg/year), making it ideal for cost-conscious businesses. The study confirms the possibility of effective integration of renewable sources with tire recycling methods. The practical use of the research results is possible during the implementation of grant projects for the recycling of used tires, and in the work of relevant government structures for devising a policy for the disposal of used tires

Identifying patterns of change in traffic flows’ parameters depending on the organization of public transport movement

This study examines the issue of traffic organization on sections of city streets, in which there are public transport stop zones of different configurations (with a drive-in pocket and along a traffic lane). Accordingly, the object of research is the parameters of traffic flows; the subject is the regularities in their change on such specific sections of the street-road network, taking into account the configuration of stops, the number of traffic lanes, and priority conditions for the movement of public transport. The task addressed in this work was the quantitative assessment of the efficiency of traffic management in public transport stop zones. It was also important to compare different configurations of street segments in terms of their impact on delays of private and public transport. As a result of the research, the speed and time characteristics of the traffic flow and their dependence on its composition and intensity for different number and specialization of traffic lanes, as well as the location of the public transport stop, were determined. The resulting quantitative indicators of delays of all types of transport for each modeling option made it possible to determine the best of them according to the criterion of minimal time loss. This applies to both private and public transport, as the values of delays may differ from each other by 10–50 %. An applied aspect related to using the scientific result is the possibility of justifying the number of traffic lanes, or their allocation for public transport, as well as determining the appropriate configuration of stops. This constitutes the prerequisites for the transfer of the scientific results to the relevant interested structures in the field of transport, which are responsible for the organization and safety of traffic under urban conditions

Zirconium-catalyzed one-pot synthesis of benzoxazoles using reaction of catechols, aldehydes and ammonium acetate

In this study, an efficient method for the synthesis of benzoxazoles by coupling catechols, aldehydes and ammonium acetate using ZrCl4 as catalyst in ethanol is reported. A wide range of benzoxazoles (59 examples) are smoothly produced in high yields (up to 97%). Other advantages of the method include large-scale synthesis and the use of oxygen as an oxidant. The mild reaction conditions allowed late-stage functionalization, facilitating access to several derivatives with biologically relevant structures such as β-lactam and quinoline heterocycles.

Can Random Friends Seed More Buzz and Adoption? Leveraging the Friendship Paradox

A critical element of word of mouth (WOM) or buzz marketing is to identify seeds, often central actors with high degree in the social network. Seed identification typically requires data on the relevant network structure, which is often unavailable. We examine the impact of WOM seeding strategies motivated by the friendship paradox, which can obtain more central nodes without knowing network structure. Higher degree nodes may be less effective as seeds if these nodes communicate less with neighbors or are less persuasive when they communicate; therefore, whether friendship paradox–motivated seeding strategies increase or reduce WOM and adoption remains an empirical question. We develop and estimate a model of WOM and adoption using data on microfinance adoption across village social networks in India. Counterfactuals show that the proposed strategies with limited seeds are about 13%–30% more effective in increasing adoption relative to random seeding. These strategies are also on average 5%–11% more effective than the firm’s leader seeding strategy. We also find these strategies are relatively more effective when we have fewer seeds. This paper was accepted by Juanjuan Zhang, marketing. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2024.4991 .

Grating-based phase-contrast computed tomography for breast tissue at an inverse compton source

The introduction of mammography screening programs has significantly reduced breast cancer mortality rates. Nevertheless, some lesions remain undetected, especially in dense breast tissue. Studies have shown that phase-contrast imaging can improve breast cancer diagnosis by increasing soft tissue contrast. Furthermore, grating-based phase-contrast imaging enables the simultaneous acquisition of absorption, phase-contrast, and scattering, so-called dark-field images. The latter allows the classification of microcalcifications. In addition, breast computed tomography (BCT) systems can identify and discriminate overlapping but clinically relevant structures. This study investigates the benefit of combining grating-based phase-contrast with BCT. We explore the potential of grating-based phase-contrast breast computed tomography (gbpc-BCT) with a breast phantom and a freshly dissected fibroadenoma. Improved image contrast could be achieved with radiation doses comparable to those used in clinical BCT.

Highly efficient image navigator based 3D whole-heart cardiac MRA at 0.55T.

To develop and evaluate a highly efficient free-breathing and contrast-agent-free three-dimensional (3D) whole-heart Cardiac Magnetic Resonance Angiography (CMRA) sequence at 0.55T. Free-breathing whole-heart CMRA has been previously proposed at 1.5 and 3T. Direct application of this sequence to 0.55T is not possible due to changes in the magnetic properties of the tissues. To enable free-breathing CMRA at 0.55T, pulse sequence design and acquisition parameters of a previously proposed whole-heart CMRA framework are optimized via Bloch simulations. Image navigators (iNAVs) are used to enable nonrigid respiratory motion-correction and 100% respiratory scan efficiency. Patch-based low-rank denoising is employed to accelerate the scan and account for the reduced signal-to-noise ratio at 0.55T. The proposed approach was evaluated on 11 healthy subjects. Image quality was assessed by a clinical expert (1: poor to 5: excellent) for all intrapericardiac structures. Quantitative evaluation was performed by assessing the vessel sharpness of the proximal right coronary artery (RCA). Optimization resulted in an imaging flip angle of , fat saturation flip angle of , and six k-space lines for iNAV encoding. The relevant cardiac structures and main coronary arteries were visible in all subjects, with excellent image quality (mean ) and minimal artifacts (mean ), with RCA vessel sharpness ( ) comparable to previous studies at 1.5T. The proposed approach enables 3D whole-heart CMRA at 0.55T in a 6-min scan ( ), providing excellent image quality, minimal artifacts, and comparable vessel sharpness to previous 1.5T studies. Future work will include the evaluation of the proposed approach in patients with cardiovascular disease.

Relationship between implementation of sustainable human resource practices and corporate market value

Orientation: The sustainable development goals (SDGs) were the context for examining the human resource (HR) expertise required in the boardroom. Achievement of SDGs depends on how boards are structured and whether members have the appropriate expertise to implement key HR practices to maximise corporate market value.Research purpose: This study aimed to critically examine the mediation effect of HR expertise in the boardroom on the relationship between implementation of human resource practices (HRPs) and market value.Motivation for the study: The study investigated whether HR expertise in the boardroom contributes to the implementation of key HRPs to achieve employee-related SDGs.Research approach/design and method: A randomised experimental design was performed through a bootstrap procedure to examine mediation. Data were collected from corporate annual reports through a self-constructed measurement instrument or disclosure index.Main findings: Overall, no evidence of a mediation was found, except in the case of HR expertise in the board and HR and/or remuneration committee, which yielded a statistically significant mediation effect on the implementation of some initiatives with confidence intervals close to zero.Practical/managerial implications: Human resource expertise in the boardroom plays a crucial role in achieving the SDGs, and the lack thereof affects the company’s market value. Therefore, the board of directors (BoDs) must prioritise sufficient HR expertise in the relevant structures to facilitate implementation of HRPs to achieve the SDGs.Contribution/value-add: This study is the first attempt of its kind in South Africa, and the results demonstrate the absence of a mediation effect, signalling that a lack of HR expertise in the boardroom could affect organisations’ achievement of the SDGs.

An automatic tracking method to measure the mandibula movement during real time MRI

Mandibular movement is complex and individual due to variations in the temporomandibular joint (TMJ). Consequently, patient-centered dentistry should incorporate patients’ specific anatomy and condylar function in treatment planning. Real-time magnetic resonance imaging (rt-MRI) visualizes relevant structures and tracks mandibular movement. However, current assessments rely on qualitative observations or time-consuming manual tracking, lacking reliability. This study developed an automatic tracking algorithm for mandibular movement in rt-MRI using least mean square registration (LMS) and compared it to manual tracking (MT) during mouth opening. Ten participants with skeletal class I underwent rt-MRI (10 frames/s). The same operator tracked the condylar pathway for the two methods, setting 2000 landmarks (2 landmarks x100 frames x10 participants) for MT and 210 landmarks (3 landmarks x7 frames x10 participants) for LMS. Time required, superimposition error, and the distance between tracked condylar pathways were compared between methods. LMS tracking was 76% faster and showed significantly better superimposition (0.0289 ± 0.0058) than MT (0.059 ± 0.0145) (p = 0.002). During one-third of the movement, the pathways tracked by both methods were more than 1 mm and 1° apart. These findings highlight the benefits of automatic condylar movement tracking in rt-MRI, laying the groundwork for more objective and quantitative observation of TMJ function.

Vitality structures in ‘addictive’ game design

For decades, research on technology use and mental health has been based on the assumption that identifiable structures of ‘design’ are psychologically relevant for their users. This has been central especially for the nosological emergence of ‘behavioural addictions’, which currently include two formal diagnoses on technology use: problems related to playing gambling games (gambling disorder) and videogames (gaming disorder). Alas, the research on identifying ‘addictive’ design structures has suffered from major construct validity issues. To make progress over those issues, I draw from the history of ‘vitality affects’ in psychiatry and introduce vitality structures as a design-phenomenological framework that can help researchers conceptualise psychologically relevant ‘bonds’ between entities of game design and corresponding player phenomenology. Vitality structures are not natural kinds to be discovered but pragmatic constructs to be used—and useful as long as they communicate what is both identifiable and empirically prevalent. As a demonstration of practice, I propose working conceptualisations of three vitality structures, which surface in videogames played by gaming treatment-seekers. Systematic research programs for identifying relevant vitality structures can lead to construct-valid and replicable design effects.

FESTA: A Polygon-Based Approach for Extracting Relevant Structures from Free Energy Surfaces Obtained in Molecular Simulations.

An easy-to-use script named FESTA (Free Energy Surface Trajectory Analysis) is provided to streamline the extraction of equilibrium structures from free energy maps obtained with enhanced sampling simulation techniques and their associated trajectories. This approach efficiently identifies relevant structures by automatically selecting minima on the free energy surface using a connected-component labeling algorithm and extracts them utilizing a Shapely-polygon-based trajectory analysis process. The script is general and portable; it incorporates an automatic periodicity detection system; and multiprocessing is utilized to leverage all available computational resources for enhanced efficiency. The effectiveness of the proposed polygon-based approach is demonstrated through comparison with a naïve and largely inefficient loop-based script and its application across three distinct systems for benchmarking purposes.