Global Reorientation Research Articles

Global reorientation of a free-fall multibody system using periodical joint motions – theory and motion planning

Global reorientation of a free-fall multibody system using periodical joint motions – theory and motion planning

The Macroeconomic Effects of Global Supply Chain Reorientation

The Macroeconomic Effects of Global Supply Chain Reorientation

Collective dipole reorganization in magnetostructures

Neodymium spherical magnets are inexpensive objects that demonstrate how dipolar particles self-assemble into various structures ranging from 1D chains to 3D crystals. Assemblies of these magnets are nicknamed magnetostructures and this paper focuses on a variety called magnetotubes, which are some curved square lattices forming cylinders. We experimentally and numerically observe that such magnetotubes can self-buckle, above a critical aspect ratio. In fact, the underlying dipolar ordering of such structures is found to exhibit a collective reorganization, altering the mechanical stability of the entire system. We identify the conditions in which these phenomena occur, and we emphasize that metastable states coexist. This suggests that a wide variety of magnetostructures, including chains and magnetocrystals, may collapse due to the coexistence of multiple ground states and global reorientation of dipoles.

Strategic directions of sustainable development of the tourism industry

Today, in the conditions of global restructuring and reorientation of economic sectors, the growth of people's needs and motives for tourism is important. Tourism as a branch of the economy is gradually taking leadership positions in many countries of the world, as well as in Ukraine in the future. Therefore, we have significant unrealized human, natural-resource, historical-cultural, tourist-recreational and scientific-technical potential, a good geographical location, and a favorable climate. Also, the peculiarity of the current situation in the country, economic and political instability, the conditions of the military conflict, insist on the further development of our state, which must necessarily include the creation of conditions for the development of the tourism industry.
 At the same time, the formation of a highly developed tourism industry and its integration into the world market of tourist services are connected with the need to solve acute socio-economic problems and attract international experience. The article reveals that the phenomenon of the 21st century. determine today - the hospitality industry, which has become one of the leading directions of socio-economic activity. It has been proven that this is the business of the 21st century. which contributes to the creation of new jobs, the search for methods of increasing the competitiveness of enterprises at the global level, the popularization of the country on the international market of services and, as a result, raising the level of the national economy.
 However, in recent years, the tourism industry in Ukraine has been in a state of stagnation, therefore, the determination of factors influencing the development of the hospitality industry is relevant, because with the help of the acquired knowledge, it is possible to prevent the degradation of one of the most promising branches of international business. The article examines the influence of factors on the sustainable development of the tourism industry, economic studies of the potential opportunities of this industry within the general strategy of the socio-economic development of the world in general and Ukraine in particular.

Local roots, global vines: Human rights museums in western Japan as expressions of identity

AbstractRecently human rights movements among Japan's Buraku people have become increasingly globalized, situating the Buraku struggle among those of other caste‐based minorities around the world. Scholars have theorized that this globalization manifests in a global–local feedback loop in which decisions made by global and local actors inform one another. In this study, I utilize field research and qualitative content analysis of brochures at three Buraku human rights museums in western Japan to investigate this global reorientation. I show that two museums correspond to global–local feedback loop theory and I further identify how local nuances affect the disparate strategies the museums employ to engage with this new globalized Buraku identity. The third museum, however, serves as a counterexample by electing to keep its exhibits locally focused, reflecting its community‐driven mission. I argue that these museums function as interlocutors of Buraku identity at both the local and global levels.

The 2022 Sanction Challenges for International Commercial Arbitration and Methods of Resolving them

The subject of this study is the impact of the sanctions policy imposed against the Russian Federation in 2022 on international commercial arbitration. For that purpose, we analyse the restrictive measures that have had a major impact on dispute resolution in international commercial arbitration involving Russian and sub-sanctioned persons. An important part of the study is an analysis of current practice in this area and the difficulties arising in order to develop recommendations and possible means of overcoming them for the continuation of international arbitration in Russia and access to justice for sanctioned persons. Over recent years, international commercial arbitration has become one of the most common means of dispute resolution, not only abroad, but also in the Russian Federation. However, the international nature of arbitration makes it highly sensitive to sanctions. Since the implementation of anti-Russian sanctions, especially in 2022, it became evident that the field of international commercial arbitration faces inevitable difficulties in terms of cooperation with foreign jurisdictions and its operation in general. The impact of restrictive measures on international commercial relations cannot be overestimated, with the number of cross-border disputes only increasing, which makes international commercial arbitration more than relevant and requires new solutions to overcome existing challenges. The research leads to a number of conclusions: the 2022 sanctions have certainly affected the world of arbitration but have not put an end to arbitration institutions in general; they have led to a global reorientation towards Asian arbitral institutions and a strengthening of Russia's position as a place for arbitration; parties to arbitration proceedings are finding new and successful solutions to the restrictive measures; many foreign jurisdictions are slowly softening their policy towards arbitration.

Global reorientation of the world economic space in the modern dimension against the background of the russian-Ukrainian war of 2014-2022

Formulation of the problem. In modern conditions, in particular after the beginning of full-scale Russian aggression against Ukraine on February 24, 2022, it poses a number of serious problems to the world in various dimensions. The economic space of world civilization is one of them. First of all, this is due to the fact that in conditions of war, especially full-scale, important factors in victory are not only the quantitative military advantage of one of the warring parties, but also economic advantages based on modern production technologies. At the same time, there are questions of consolidation of the world community on the side of the country that fell victim to the aggressor country. In this particular case, we are talking about Ukraine, which was attacked by the Russian Federation. It is the consolidation of European Union member states, NATO member states, as well as individual countries such as the United States, Great Britain, Canada, Poland, Germany, Japan, Australia and other countries that strengthens Ukraine's unequal struggle with Russia. In addition, the role of international organizations such as the UN, the EU, the World Trade Organization and others cannot be underestimated. Combining the efforts of individual states, international organizations, and international economic systems that oppose the aggressive policy of the Russian Federation, undermines the efforts of the aggressor country in the sphere of world domination. The economic sanctions imposed by the world's leading countries and international organizations at the very beginning of Russia's full-scale aggression against Ukraine put the economy of the aggressor country, in particular its financial system, on the brink of disaster. Practically today there is a reorientation and reorganization of the world economic civilization system and the creation of a new paradigm of economic security. This is the largest transformation since the Second World War, as the security mechanisms in general and economic security in particular, enshrined in the UN Charter, the 1975 Helsinki Accords do not provide any guarantees today. Even the Budapest Memorandum, which guaranteed Ukraine's security and territorial integrity, did not work and was violated by the Russian Federation, which signed the document. Analysis of recent research and publications. At the moment, there are no fundamental and generalizing works on this subject, as the topic itself is quite new and requires a comprehensive study in the future. At the same time, there are a large number of assessments of the current situation and prospects for the development of the world's civilized economic global space. The purpose of this study is to determine the possible prospects for the transformation of the world's civilized economic space and the new place of Ukraine in this system. Results of the research. The article attempts to consider the prospects of global reorientation of the world economic space in the context of modern large-scale changes against the background of the Russian-Ukrainian war. Conclusions. As a result of the full-scale aggression of the Russian Federation against Ukraine, it posed a number of serious risks to the world community in the economic, political, military, environmental and other spheres. The world had to react to the disturbance of world balance and balance caused by Russia's aggressive policy. As a result, a number of decisive steps have been taken by the world community in the field of reorientation of the global economic space.

Surveying the Side-Chain Network Approach to Protein Structure and Dynamics: The SARS-CoV-2 Spike Protein as an Illustrative Case.

Network theory-based approaches provide valuable insights into the variations in global structural connectivity between different dynamical states of proteins. Our objective is to review network-based analyses to elucidate such variations, especially in the context of subtle conformational changes. We present technical details of the construction and analyses of protein structure networks, encompassing both the non-covalent connectivity and dynamics. We examine the selection of optimal criteria for connectivity based on the physical concept of percolation. We highlight the advantages of using side-chain-based network metrics in contrast to backbone measurements. As an illustrative example, we apply the described network approach to investigate the global conformational changes between the closed and partially open states of the SARS-CoV-2 spike protein. These conformational changes in the spike protein is crucial for coronavirus entry and fusion into human cells. Our analysis reveals global structural reorientations between the two states of the spike protein despite small changes between the two states at the backbone level. We also observe some differences at strategic locations in the structures, correlating with their functions, asserting the advantages of the side-chain network analysis. Finally, we present a view of allostery as a subtle synergistic-global change between the ligand and the receptor, the incorporation of which would enhance drug design strategies.

Seismic Crustal Structure and Morphotectonic Features Associated With the Chain Fracture Zone and Their Role in the Evolution of the Equatorial Atlantic Region.

Oceanic transform faults and fracture zones (FZs) represent major bathymetric features that keep the records of past and present strike‐slip motion along conservative plate boundaries. Although they play an important role in ridge segmentation and evolution of the lithosphere, their structural characteristics, and their variation in space and time, are poorly understood. To address some of the unknowns, we conducted interdisciplinary geophysical studies in the equatorial Atlantic Ocean, the region where some of the most prominent transform discontinuities have been developing. Here we present the results of the data analysis in the vicinity of the Chain FZ, on the South American Plate. The crustal structure across the Chain FZ, at the contact between ∼10 and 24 Ma oceanic lithosphere, is sampled along seismic reflection and refraction profiles. We observe that the crustal thickness within and across the Chain FZ ranges from ∼4.6–5.9 km, which compares with the observations reported for slow‐slipping transform discontinuities globally. We attribute this presence of close to normal oceanic crustal thickness within FZs to the mechanism of lateral dike propagation, previously considered to be valid only in fast‐slipping environments. Furthermore, the combination of our results with other data sets enabled us to extend the observations to morphotectonic characteristics on a regional scale. Our broader view suggests that the formation of the transverse ridge is closely associated with a global plate reorientation that was also responsible for the propagation and for shaping lower‐order Mid‐Atlantic Ridge segmentation around the equator.

РОЗВИТОК ІНДУСТРІЇ ТУРИЗМУ ТА ГОСТИННОСТІ В УКРАЇНІ

Сьогодні в умовах глобальних перебудов і переорієнтації галузей економіки важливим є зростання потреб і мотивів людей до туристичної діяльності. Туризм як галузь економіки поступово займає лідерські позиції в багатьох країнах світу, а також у перспективі і в Україні. Отже, маємо значний нереалізований людський, природно-ресурсний, історико-культурний, туристично-рекреаційний та науково-технічний потенціал, вдале географічне розміщення, сприятливий клімат. Також особливості ситуації в країні, економічна та політична нестабільність, умови військового конфлікту підштовхують до подальшої розбудови нашої держави, яка обов’язково повинна включати створення умов для розвитку туристичної галузі. При цьому формування високорозвинутої індустрії туризму та її інтеграція у світовий ринок туристичних послуг пов’язані з необхідністю вирішення гострих соціально-економічних проблем і залучення міжнародного досвіду. У статті розкрито, що феноменом ХХІ ст. визначають сьогодні індустрію гостинності, що стала одним із провідних напрямів соціально-економічної діяльності. Доведено, що це бізнес ХХІ ст., який сприяє створенню нових робочих місць, пошуку методів підвищення конкурентоспроможності підприємств на світовому рівні, популяризації країни на міжнародному ринку послуг та, як наслідок, підвищенню рівня національної економіки. Проте впродовж останніх років індустрія гостинності в Україні перебуває у стані стагнації, тому визначення факторів впливу на розвиток індустрії є актуальним, адже за допомогою отриманих знань можна запобігти деградації однієї з найперспективніших галузей міжнародного бізнесу. У статті розглянуто вплив чинників на розвиток індустрії гостинності, економічні дослідження потенційних можливостей цієї галузі в межах загальної стратегії соціально-економічного розвитку світу загалом та України зокрема.

The China-UK Global Health Support Programme: looking for new roles and partnerships in changing times

China’s engagement in global affairs has changed substantially in the 2010s. One aspect of the country’s global reorientation has been its increased interest in, and willingness to play a role in, global health. In the early 2010s, the UK Department for International Development (DFID) initiated a collaboration with the Chinese government on a programme to support the country to play a greater and more effective global role in health and explore how the UK and China could work together on issues of key concern and contribute to improved global development outcomes. The programme worked with key Chinese agencies to carry out capacity building, support analysis of China’s approaches to engagement in global health governance and assistance, and provide support to government decision making. It also trialled several small-scale interventions in third countries through which Chinese agencies gained experience of working on health programmes overseas. The article reports on the main findings of an evaluation commissioned by DFID to learn from the programme. The programme provided support at a key time in China’s global reorientation; however, there is a need for continued development of capacity and systems for China to play the role envisaged by the country’s leadership. There is also a need for continued exploration on the part of China and partners of how to effectively collaborate to support improved global outcomes.

Binge Alcohol Exposure in Adolescence Impairs Normal Heart Growth.

BackgroundApproximately 1 in 6 adolescents report regular binge alcohol consumption, and we hypothesize it affects heart growth during this period.Methods and ResultsAdolescent, genetically diverse, male Wistar rats were gavaged with water or ethanol once per day for 6 days. In vivo structure and function were assessed before and after exposure. Binge alcohol exposure in adolescence significantly impaired normal cardiac growth but did not affect whole‐body growth during adolescence, therefore this pathology was specific to the heart. Binge rats also exhibited signs of accelerated pathological growth (concentric cellular hypertrophy and thickening of the myocardial wall), suggesting a global reorientation from physiologic to pathologic growth. Binge rats compensated for their smaller filling volumes by increasing systolic function and sympathetic stimulation. Consequently, binge alcohol exposure increased PKA (protein kinase A) phosphorylation of troponin I, inducing myofilament calcium desensitization. Binge alcohol also impaired in vivo relaxation and increased titin‐based cellular stiffness due to titin phosphorylation by PKCα (protein kinase C α). Mechanistically, alcohol inhibited extracellular signal‐related kinase activity, a nodal signaling kinase activating physiology hypertrophy. Thus, binge alcohol exposure depressed genes involved in growth. These cardiac structural alterations from binge alcohol exposure persisted through adolescence even after cessation of ethanol exposure.ConclusionsAlcohol negatively impacts function in the adult heart, but the adolescent heart is substantially more sensitive to its effects. This difference is likely because adolescent binge alcohol impedes the normal rapid physiological growth and reorients it towards pathological hypertrophy. Many adolescents regularly binge alcohol, and here we report a novel pathological consequence as well as mechanisms involved.

Discerning Dynamic Signatures of Membrane-Bound α-Synuclein Using Site-Specific Fluorescence Depolarization Kinetics.

α-Synuclein is an intrinsically disordered protein that adopts an α-helical structure upon binding to the negatively charged lipid membrane. Binding-induced conformational change of α-synuclein plays a crucial role in the regulation of synaptic plasticity. In this work, we utilized the fluorescence depolarization kinetics methodology to gain the site-specific dynamical insights into the membrane-bound α-synuclein. We took advantage of the nonoccurrence of Cys in α-synuclein and created single-Cys variants at different sites for us to be able to label it with a thiol-active fluorophore. Our fluorescence depolarization results reveal the presence of three dynamically distinct types of motions of α-synuclein on POPG (1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol)) small unilamellar vesicles (SUVs): (i) the (local) wobbling-in-cone motion of the fluorophore on the subnanosecond timescale, (ii) the backbone segmental mobility on the nanosecond timescale, and (iii) a slow depolarization component with a characteristic long rotational correlation time (∼60 ns) that is independent of the residue position. This characteristic timescale could potentially arise due to global tumbling of the protein-membrane complex, the global reorientation of only the protein within the membrane, and/or the translation diffusion of the protein on the curved membrane surface that could result in fluorescence depolarization due to the angular displacement of the transition dipole. In order to discern the molecular origin of the characteristic long rotational correlation time, we then carried our depolarization experiments varying the curvature of the membrane and varying the binding affinity by changing the lipid headgroup. These experiments revealed that the long rotational correlation time primarily arises due to the translational diffusion of α-synuclein on the curved membrane surface with a diffusion coefficient of ∼8.7 × 10-10 m2/s. The site-specific fluorescence depolarization methodology will find broad application in quantifying diffusion of a wide range of membrane-associated proteins involved in functions and diseases.

Telomere length in depression and association with therapeutic response to electroconvulsive therapy and cognitive side-effects.

Electroconvulsive therapy (ECT) is the most acutely effective treatment for severe treatment-resistant depression. However, there are concerns about its cognitive side-effects and we cannot yet confidently predict who will experience these. Telomeres are DNA-protein complexes that maintain genomic integrity. In somatic cells, telomeres shorten with each cell division. Telomere length (TL) can thus provide a measure of 'biological' aging. TL appears to be reduced in depression, though results are mixed. We sought to test the following hypotheses: (1) that TL would be shorter in patients with depression compared to controls; (2) that TL would be a predictor of response to ECT; and (3) that shorter TL would predict cognitive side-effects following ECT. We assessed TL in whole blood DNA collected from severely depressed patients (n = 100) recruited as part of the EFFECT-Dep Trial and healthy controls (n = 80) using quantitative real-time polymerase chain reaction. Mood and selected cognitive measures, including global cognition, re-orientation time, and autobiographical memory, were obtained pre-/post-ECT and from controls. Our results indicate that TL does not differ between patients with depression compared to controls. TL itself was not associated with mood ratings and did not predict the therapeutic response to ECT. Furthermore, shorter baseline TL is not a predictor of cognitive side-effects post-ECT. Overall, TL assessed by PCR does not represent a useful biomarker for predicting the therapeutic outcomes or risk for selected cognitive deficits following ECT.

Dynamics of a pair of ellipsoidal microparticles under a uniform magnetic field

Under a uniform magnetic field, magnetic particles tend to form chains, clusters or columns due to particle–particle interactions. Non-spherical magnetic particles dispersed in a liquid medium show different rheological properties. However, there is a lack of knowledge about the fundamental mechanism of particle–particle interactions of non-spherical particles under a uniform magnetic field. In this work, we numerically investigate the particle–particle interactions and relative motions of a pair of paramagnetic elliptical particles by using direct numerical simulations to create two-dimensional models that resolve the magnetic and flow fields around the finite-sized particles. The modeling is based on the finite element method and arbitrary Lagrangian–Eulerian approach with full consideration of particle–fluid–magnetic field interaction. The effects of initial position and aspect ratio of the particles are investigated. The results show that the particles spend much more time under global reorientation than local magneto-orientation. Larger initial relative angles and distances, and larger aspect ratios, tend to require more time to form a stable chain. The particle–particle interactions and relative motion of a pair of elliptical particles in this study provide insights into the particle alignment and chaining processes under uniform magnetic fields, which are closely related to the response of magneto-rheological fluids to magnetic fields.

Crossing boundaries: Global reorientation following transfer from the inside to the outside of an arena.

In 2 spatial navigation experiments, human participants were asked to find a hidden goal (a WiFi signal) that was located in 1 of the right-angled corners of a kite-shaped (Experiment 1) or a cross-shaped (Experiment 2) virtual environment. Goal location was defined solely with respect to the geometry of the environment. Following this training, in a test conducted in extinction, participants were placed onto the outside of the same environments and asked to locate the WiFi signal. The results of both experiments revealed that participants spent more time searching in regions on the outside of the environments that were closest to where the WiFi signal was located during training. These results are difficult to explain in terms of analyses of spatial navigation and reorientation that emphasize the role of local representational encoding or view matching. Instead, we suggest that these results are better understood in terms of a global representation of the shape of the environment.

Incorporation of Putative Helix-Breaking Amino Acids in the Design of Novel Stapled Peptides: Exploring Biophysical and Cellular Permeability Properties.

Stapled α-helical peptides represent an emerging superclass of macrocyclic molecules with drug-like properties, including high-affinity target binding, protease resistance, and membrane permeability. As a model system for probing the chemical space available for optimizing these properties, we focused on dual Mdm2/MdmX antagonist stapled peptides related to the p53 N-terminus. Specifically, we first generated a library of ATSP-7041 (Chang et al., 2013) analogs iteratively modified by L-Ala and D-amino acids. Single L-Ala substitutions beyond the Mdm2/(X) binding interfacial residues (i.e., Phe3, Trp7, and Cba10) had minimal effects on target binding, α-helical content, and cellular activity. Similar binding affinities and cellular activities were noted at non-interfacial positions when the template residues were substituted with their d-amino acid counterparts, despite the fact that d-amino acid residues typically ‘break’ right-handed α-helices. d-amino acid substitutions at the interfacial residues Phe3 and Cba10 resulted in the expected decreases in binding affinity and cellular activity. Surprisingly, substitution at the remaining interfacial position with its d-amino acid equivalent (i.e., Trp7 to d-Trp7) was fully tolerated, both in terms of its binding affinity and cellular activity. An X-ray structure of the d-Trp7-modified peptide was determined and revealed that the indole side chain was able to interact optimally with its Mdm2 binding site by a slight global re-orientation of the stapled peptide. To further investigate the comparative effects of d-amino acid substitutions we used linear analogs of ATSP-7041, where we replaced the stapling amino acids by Aib (i.e., R84 to Aib4 and S511 to Aib11) to retain the helix-inducing properties of α-methylation. The resultant analog sequence Ac–Leu–Thr–Phe–Aib–Glu–Tyr–Trp–Gln–Leu–Cba–Aib–Ser–Ala–Ala–NH2 exhibited high-affinity target binding (Mdm2 Kd = 43 nM) and significant α-helicity in circular dichroism studies. Relative to this linear ATSP-7041 analog, several d-amino acid substitutions at Mdm2(X) non-binding residues (e.g., d-Glu5, d-Gln8, and d-Leu9) demonstrated decreased binding and α-helicity. Importantly, circular dichroism (CD) spectroscopy showed that although helicity was indeed disrupted by d-amino acids in linear versions of our template sequence, stapled molecules tolerated these residues well. Further studies on stapled peptides incorporating N-methylated amino acids, l-Pro, or Gly substitutions showed that despite some positional dependence, these helix-breaking residues were also generally tolerated in terms of secondary structure, binding affinity, and cellular activity. Overall, macrocyclization by hydrocarbon stapling appears to overcome the destabilization of α-helicity by helix breaking residues and, in the specific case of d-Trp7-modification, a highly potent ATSP-7041 analog (Mdm2 Kd = 30 nM; cellular EC50 = 600 nM) was identified. Our findings provide incentive for future studies to expand the chemical diversity of macrocyclic α-helical peptides (e.g., d-amino acid modifications) to explore their biophysical properties and cellular permeability. Indeed, using the library of 50 peptides generated in this study, a good correlation between cellular permeability and lipophilicity was observed.

Speaking out: A postcolonial critique of the academic discourse on far-right populism

Brexit and Trump’s victory in the United States has sparked renewed academic interest in far-right populism. However, this academic discourse remains remarkably orientalist in its tenor and rhetoric. The focus of academic debates remains restricted to dissecting the rise of far-right populism in the Global North West, while similar movements in Global South East remain largely ignored. We argue that the contemporary academic discourse about the far-right populism is based on the fundamental assumption that the ‘normal’ Global North West is becoming ‘abnormal,’ while the question of abnormality or lack thereof of the proverbial Orient is not taken up because in such othering discourse, the option of normality is foreclosed to the Global South East. Using the rise of the Bharatiya Janta Party in India as an example, we contend that far-right populist movements in the Global South East have developed and intersect with businesses and government in unique ways. The embrace of neoliberalism by the Indian far-right, a stark contrast to similar movements in the Global North West, further suggests that we might be witnessing a global reorientation of the capitalist order. Therefore, a comprehensive analysis of far-right populism must account for and pay attention to the heterogeneities of these movements across the Global North West and the Global South East.

Global Latin(X) AmericanXs: Charting new ontological and epistemological cartographies beyond US LatinX studies

This article examines how situating our academic inquiry from geographic vantage points outside of the United States allows scholars to recast epistemological and ontological assumptions in the field of US Latina/o Studies. It asks how, from a global reorientation of the cognitive map of US Latina/o Studies, we might reconsider the experience of the Latin American and Caribbean diaspora and the notion of Latinidad in places such as Jordan, Spain, and Canada. This analysis places Latina/o Studies and Latin American and Caribbean Studies into conversation by reconsidering their status as traditionally isolated epistemic sites of US ethnic and area studies. In addition, it explores how new “Latino” and diasporic identities are forged through hybrid ethnic interactions among minoritized populations in the Global South.

Testing principal- versus medial-axis accounts of global spatial reorientation.

Determination of a direction of travel is a necessary component of successful navigation, and various species appear to use the geometric shape (global geometric cues) of an environment to determine direction. Yet, debate remains concerning which objective shape parameter is responsible for spatial reorientation via global geometric cues. For example, the principal axis of space, which runs through the centroid and approximate length of the space, and the medial axis of space, a trunk and branch system that fills the shape, have each been suggested as a basis to explain global spatial reorientation. As the principal- and medial-axis accounts appear to have substantial theoretical implications regarding the nature of shape perception, spatial memory, and the underlying psychological representations of space, it appears critical to empirically differentiate between these global geometric accounts. The present experiment explicitly placed predictions from the principal- and medial-axis-based accounts of global spatial reorientation in conflict for theoretical diagnostic purposes. We used a standard reorientation paradigm in which human participants first reoriented in a rectangular environment; subsequent testing in a critical I-shaped enclosure allowed dissociation of the principal- or medial-axis-based accounts. We show that reorientation in the I-shaped enclosure was consistent with the principal-axis account and inconsistent with the medial-axis account. We suggest that the use of the principal axis for spatial reorientation is a relatively simple and efficient way to establish directionality that would be advantageous over a more complex and less efficient medial-axis-based account. (PsycINFO Database Record