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Back-to-back correlations for finite expanding fireballs

Back-to-back correlations for finite expanding fireballs

Recently, it has been shown [1,2] that large back-to-back correlations (BBC) of particle-antiparticle pairs of bosonic particles might appear in high energy nucleus-nucleus colli- sions as a consequence of in-medium mass modification of the bosons. Detailed calculations indicate that the BBC signal appears for values of transverse momenta below 1–2 GeV/c. More recently, it was shown [3] that BBC of similar strength might appear for fermionic particles as well. The main physical ingredient used in the evaluation of the effects of in-medium modified masses on two particle correlation functions is a quantum-mechanical correlation induced by a nonzero overlap between in-medium and free states. The induced quantum mechanical correlation can be represented in terms of two- mode squeezed states of the asymptotic, observable states and is implemented through a Bogoliubov-Valatin transformation. The possibility of measuring a significant BBC signal in heavy-ion collisions opens new interesting possibilities for accessing the properties of the matter formed in such collisions. The BBC signal is linked to in-medium mass modifications of hadrons in the hot and dense environment the detected particles experience before freezing out and in this sense BBC measurements provide independent pieces of information on medium modifications from the ones obtained from dilepton yields and spectra. However, there are several additional physical effects that interfere with mass modifications of the detected particles in the interpretation of the BBC signal.
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Sistemas de controle aplicados a aerogeradores síncronos com conversores Back-to-Back

Sistemas de controle aplicados a aerogeradores síncronos com conversores Back-to-Back

O trabalho de disserta¸c˜ao apresenta as principais conceitos do sistema de gera¸c˜ao e´olica e a tecnologia de aerogerador baseada no geradores s´ıncro- nos conectados `a rede el´etrica atrav´es de um conversor Back-to-Back. Uma modelagem matem´atica dos principais componentes do sistema de gera¸c˜ao ´e desenvolvida neste trabalho assim como o projeto dos controladores uti- lizados para comandar o sistema. O sistema de gera¸c˜ao e´olica proposto ´e constru´ıdo em laborat´orio assim como a nova plataforma de controle base- ado em uma hardware de ponto flutuante para permitir a realiza¸c˜ao de teste experimentais. A turbina e´olica ´e representada por um motor de indu¸c˜ao mecanicamente acoplado ao gerador s´ıncrono. Neste trabalho s˜ao utilizadas t´ecnicas de controle cl´assicas do tipo PI no referencial s´ıncrono e n˜ao-linear baseado em passividade. Um estudo te´orico sobre as leis de controle Inter- connection and Damping Assignment Passivity-based Control IDA-PBC no contexto da aplica¸c˜ao ´e realizado e o projeto dos controlador ´e apresentado e a influˆencia dos parˆametros do controlador IDA-PBC ´e discutida. T´ecnicas de rastreamento de m´axima potˆencia do gerador e´olico s˜ao desenvolvidas para o sistema simulado e pr´atico. Por fim os resultados simulados e experimentais para o sistema desenvolvido s˜ao apresentados e discutidos.
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Disappearance of squeezed back-to-back correlations: a new signal of hadron freeze-out from a supercooled quark gluon plasma

Disappearance of squeezed back-to-back correlations: a new signal of hadron freeze-out from a supercooled quark gluon plasma

For illustrating other interesting features found in this pre- liminary analysis and shown in Fig.(3), we chose the case with two-regions, as briefly delineated above. It also allows for some comparison with the result on Fig.(2). In parts (a) and (b) of Fig.(3), we can see that, depending on the momenta of the back-to-back pairs suffering the squeezing correlation, the signal is weaker when flow is present (for |k| ≃ 1000 MeV/c), almost unaffected by flow (for |k| ≃ 750 MeV/c), or even slightly stronger in the presence of moderate flow (for |k| < 500 MeV/c), for the set of parameters chosen in those calculations. If flow is absent, however, a monotonically in- crease can be observed with increasing values of the pair mo- menta, |k|. A more complete view of the behavior of the max- imum of the φφ back-to-back correlation can be seen in the parts (c) and (d) of Fig.(3). It is evident that back-to-back cor- relation function has a steeper growth with momentum in the no flow case, for the same values of the shifted mass, m ∗ . The moderate flow picture considered in this study still causes the growth of the BBC with |k|, but in a considerably smaller rate. With this broader panorama in mind, it is easier to understand the plots (a) and (b) of Figs. (2) and (3). Finally, we see that the strength of the signal is directly proportional to the size where the mass-shift occurs. Although the values of |k| were not the same in those two figures, but already knowing that the signal grows with increasing |k|, we see that the strength in Fig. (2), where the system size is R = 7 fm, is bigger than the corresponding ones in Fig. (3), in which the squeezing region has R s = 5 fm, even for |k| = 1000 GeV/c.
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DYNAMIC RESPONSE OF WIND POWER GENARATORS USING STATCOM

DYNAMIC RESPONSE OF WIND POWER GENARATORS USING STATCOM

The other two generationg systems are variable –speed systems. In the doubly fed induction generator, a back to back voltage source converter feeds the three phase rotor winding , Resulting that the mechanical and electrical rotor frequency are decoupled and the electrical stator and rotor frequency can match independently of the mechanical rotor speed. In the direct-drive synchronous generator, the generator is completely decoupled from the grid by power electronics, as a converter is connected to the stator winding and another converter is connected to the grid. Thus the total power delivered by the wind power is transmitted by an HVDC link.
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Worldliness in Out of the Way Places

Worldliness in Out of the Way Places

We have routinely treated these acts as mimicry as embodiments of a desire to be like us. James Ferguson, for example, recently uses such everyday instances of stylistic appropriation to highlight the claims such locals make “for equal rights of membership in a spectacularly unequal global society” (2002: 565). A claim to equal rights as they have been defined in the West is one kind of moral mutuality. Yet, mimicry entails its obverse — their assertion that we are, or at least should be, like them. And it is in the obverse that the cultural particularity of the local reveals itself (Gable, 2002). In what follows I would like to consider that obverse, by arguing that while Manjaco and Lauje might look like us and at times alike in this shared aspiration, they talk very differently about what they expect of us in a world we mutually make. This, I will assert is what those two back-to-back field- work encounters taught me. But I learned this lesson only by starting to think of Manjaco youth as more of a piece with their elders, that is more like Lauje youth than I had initially assumed. And this, as I suggested above, may be because I visited Lauje first Manjaco second. Had the reverse been the case, perhaps I would have found or sought out much more in the way of ruptures and differ- ence between Lauje youth and their elders. I will argue, however, that we can recover, out of their seeming similarity, deeper and more theoretically productive differences. Clearly that endeavour is a current concern among anthropologists who are looking at cosmopolitan youth in Africa’s villages and cities today. By stressing generational continuity rather than rupture, we can escape older bina- ries where cosmopolitanism endlessly is contrasted to tradition as new is to old, youth is to elder. We can also use an anthropology of out-of-the-way places to contribute to the literature on the varieties of cosmopolitan moral mutuality. For, even though Manjaco and Lauje youth resemble each other in their desire for elsewheres, they participate in very different understandings of how to manage a world we mutually make.
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Rev. Bras. Reumatol.  vol.55 número1

Rev. Bras. Reumatol. vol.55 número1

One goal of the locomotion is to move the body in the space at the most economical way possible. However, little is known about the mechanical and energetic aspects of locomotion that are affected by low back pain. And in case of occurring some damage, little is known about how the mechanical and energetic characteristics of the locomotion are manifested in functional activities, especially with respect to the energy-minimizer mechanisms during locomotion. This study aimed: a) to describe the main energy-minimizer mechanisms of locomotion; b) to check if there are signs of damage on the mechanical and energetic char- acteristics of the locomotion due to chronic low back pain (CLBP) which may endanger the energy-minimizer mechanisms. This study is characterized as a narrative literature review. The main theory that explains the minimization of energy expenditure during the loco- motion is the inverted pendulum mechanism, by which the energy-minimizer mechanism converts kinetic energy into potential energy of the center of mass and vice-versa during the step. This mechanism is strongly influenced by spatio-temporal gait (locomotion) parame- ters such as step length and preferred walking speed, which, in turn, may be severely altered in patients with chronic low back pain. However, much remains to be understood about the effects of chronic low back pain on the individual’s ability to practice an economic loco- motion, because functional impairment may compromise the mechanical and energetic characteristics of this type of gait, making it more costly. Thus, there are indications that such changes may compromise the functional energy-minimizer mechanisms.
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ARC Ratings: the periphery strikes back

ARC Ratings: the periphery strikes back

Overall I believe that it was a successful business move that took action over a market opportunity that appeared through one of the biggest financial crisis of the modern times. We should not forget that ARC’s joint venture was put in action by José Poças Esteves, the CEO of a small Portuguese rating company (Companhia Portuguesa de Ratings) that had a very small foothold in the minuscule Portuguese market. He was able to use his knowledge of the European ratings market to sell a, maybe utopian, idea that by unifying efforts the “smaller” players could rise against the bigger players that had controlled the market for so long and take a seat at the “Big 3 table”. Consequently, he took action and, from a company that would probably fade out from existence (CPR), formed the ARC Ratings joint venture, that even not fulfilling his wish of becoming the new “big player in the playground”, is now a strong and stable player on the geographical areas that it operates. In Europe ARC has a major expression in Portugal, as expected, but has potential to grow with the recovery of the economy. The segment of companies’ ratings, specially SME’s (small and medium enterprises), is growing due to the obligation/best practice of having a certified rating issued to pursue loans from banks and private investors.
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Low Back Pain During Streptokinase Infusion

Low Back Pain During Streptokinase Infusion

plasminogen activator, and the patient no longer complai- ned of pain. The authors emphasized that no patient deve- loped a rash, hypotension, urticaria, edema glottidis, or any other symptom suggesting an allergic manifestation. As all 5 patients had enzyme findings compatible with acute myo- cardial infarction, the authors raised the hypothesis that the low back pain could have resulted from an effect secondary to lysis of an intracoronary thrombus.

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Ultrasound-guided facet block to low back pain: a case report

Ultrasound-guided facet block to low back pain: a case report

The facet joint block is indicated for patients with low back pain for more than six months and with imaging stud- ies (computed tomography or magnetic resonance imaging of the lumbar spine) to confirm the facet osteoarthrosis. These patients must not have local or systemic infection, allergy to corticosteroids or anesthetics, coagulopathy, or be pregnant. The pain worsens with maneuvers of ipsilateral lateralization and spinal extension; the pain is relieved with contralateral lateralization and spinal flexion. Paraspinal muscle contracture may also occur. Imaging studies must be negative for vertebral tumor, discitis, disk herniation, and spinal fracture and instability. 15
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Fisioter. mov.  vol.28 número4

Fisioter. mov. vol.28 número4

According to the World (ealth Organization W(O , about % of adults will experience at least one episode of low back pain at some point in their lives, and in % of cases, the initial pain will be- come chronic . LBP is the second major cause of functional disability, being surpassed only by head- ache. )t is a leading cause of work absenteeism in developed countries. For this reason, besides being a health problem, it also leads to a considerable eco- nomic loss - .

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Back to the future of alternative banks and patient capital

Back to the future of alternative banks and patient capital

To explore historical and statistical evidence about complementary relations across these domains, it is important to recognize four different theoretical approaches to patient capital at alternative banks. The first is social economy. For theories of social economy, savings banks and cooperative banks were founded to help citizens and farmers not served by private commercial banks. Development banks were founded as institutions for national or regional public policy. From the perspective of social economy, these banks were not designed to maximize profits but, instead, to reach bankless groups or realize social or public policy missions. Savings banks and cooperative banks should therefore be evaluated by the degree to which they help excluded groups to accumulate savings and obtain credit, finance and other banking services. Similarly, special purpose banks should be evaluated by how they contribute to policy missions.
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Global shortage of technical agars: back to basics (resource management)

Global shortage of technical agars: back to basics (resource management)

In Spain, where the harvest has been based on the gathering of cast seaweed resulting from natural breakage during au- tumn storms, the observed crash in landings since early 1990s could not have been caused by over-exploitation of resources. The poor quality of storm-tossed seaweeds, highly contaminated with sand and other seaweeds, and the large fluctuations in yearly landings posed a serious problem to the industry that required a steady input of high-quality raw material. Quintano et al. (2017) suggested that light and nutri- ent availability and wave energy may be involved in the re- duction of G. corneum beds in Euskadi. These factors explain why the industry started importing the better quality (and low- er priced) Moroccan Gelidium, which were hand-picked by divers. Melo (1998) reported that in the early 1990s, more than 80% of the Moroccan exports of G. corneum were to Spain. Following the Prestige oil-spill in 2002, the Gelidium harvest was closed and Spanish agar factories increased the import of raw material from Morocco. As a consequence the price of locally harvested G. corneum dropped sharply and many harvesters abandoned the activity (A. Borja, pers. comm.). In the 2010s the whole sector declined in Spain. There are no statistics gathered at a national or regional level, both for landings and agar production, and the industry is losing its former world importance, particularly for production of bacteriological-grade agar (J. Salinas, pers. comm.). Only the production of agarose is still important.
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Back pain during pregnancy: a longitudinal study

Back pain during pregnancy: a longitudinal study

(12 weeks, 20 weeks, 32 weeks and 37 weeks). The feasibility of this parametric test results from the presence of a normal distribution at different mo- ments of evaluation was obtained with the use of normality tests: Shapiro-Wilk and Kolmogorov- -Smirnov test. It was also important to examine the observed power of the test in association with the ANOVA. The power represents the probability of correctly rejecting H0 (i.e. when H0 is false). Thus, the greater the observed power, the greater the degree of confidence in the conclusion obtai- ned. If the observed power of the test is low (less than 0.80) the results must be interpreted with cau- tion (Maroco 2003). ANOVA revealed a significant result at p ≤ 0.001 which indicates the existence of differences between the different periods, and the excellent power of the test (above 0.80). In order to identify the distinct moments, the Bonferroni test was used.
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Braz. J. Phys. Ther.  vol.15 número5

Braz. J. Phys. Ther. vol.15 número5

At present, we are conducting a randomized controlled trial, comparing the efect of these two techniques in 148 pa- tients with chronic low back pain. he present article shows the results of the irst phase, which is a feasibility study with 18 participants so that it will be possible to analyze its progress. he objective of the randomized controlled trial is to compare the efects of the Back School and Mckenzie’s techniques in pa- tients with chronic non-speciic low back pain for the following outcomes: pain intensity, disability and trunk lexion range of motion (ROM). As this study has not yet been completed, the speciic aim of this study was to assess its feasibility, showing its progress and, additionally, to identify whether there is a improvement in these patients with chronic non-speciic low back pain, regardless the intervention allocated.
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Arq. Bras. Cardiol.  vol.87 número5

Arq. Bras. Cardiol. vol.87 número5

There is plenty of asymmetry as to procedures, and in view of this, cardiologists got used to depositing knowledge into the data bank of Cardiology, and withdraw such knowledge in the form of organized packages, on behalf of the specialty’s good quality. There is something somewhat like solidarity in procedures which are recommended or discouraged, in those that are advisable and those that would be ineffective. Different medical facilities adopt specifications for the care of patients with valve diseases which are more or less common, but variations in these procedures are needed, even if only to ensure adaptation to cultural differences. In large centers, different attitudes towards the same clinical situation are just a few miles apart, whereas in a medical congress they’re only centimeters apart. However, here there is no place for “How long…?”, as the plurality of views among cardiologists is the high-yield fuel that makes Cardiology advance.
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Sediment Sampling in Estuarine Mudflats with an Aerial-Ground Robotic Team

Sediment Sampling in Estuarine Mudflats with an Aerial-Ground Robotic Team

We are currently preparing a full environmental monitoring campaign to validate the proposed experimental protocol and further assess the robustness and accuracy of the robotic system when facing the burdens of long field operations. As future work, we expect to allow the expert to dynamically (re)design the mission workflow, i.e., the set of interactions between operator and robotic team mates [50]. In the present study, the ground vehicle has been tele-operated to fulfil its mission. In the future, we intend to study the impact of autonomous behavior in the mission workflow. Automatic recharging of the sample containers once these are filled would help to reduce the physical engagement of the human expert. Additionally, it would be greatly advantageous if the aerial mosaic could be automatically segmented into the key features of the environment (e.g., water ponds, sea grass coverage). Ideally, the system should be able to progressively refine its image classifiers from data gathered in previous missions. We also expect to include energy-aware multi-robot path planning strategies so as to enable efficient soil sediment sampling campaigns in demanding environments (e.g., non-planar, with large areas of loose sand). In fact, long-lasting operation in remote sites may also require the path planner to also take into account energy harvesting activities. A self-washing mechanism will be included in the robotic solution in order to avoid material wearing and sensors/actuators malfunction. In addition, the robotic system will be extended so as to include our water surface unmanned vehicle [16] for joint water/land sampling. The experimental protocol will also be adapted to account for the extended robotic team. Finally, we also intend to fit our previous work in cooperative terrain perception of aerial-aquatic robotic teams [16] to the aerial-ground case. The goal is to to expand the ground vehicle’s look-ahead capabilities, fostering more efficient and safer navigation in demanding terrain.
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Jack and Harry: No turning back, de Tony Mckenna e Mervyn Davis e a adaptação do yarn para o romance na literatura juvenil australiana

Jack and Harry: No turning back, de Tony Mckenna e Mervyn Davis e a adaptação do yarn para o romance na literatura juvenil australiana

The yarn, as a text genre, refers to a mode of oral folk literature very popular and widespread in Australia, which presents some similarities to the “causo” in Brazil and the tall tale in the U.S. This article attempts to examine the adaptation of the yarn to suit a contemporary teen and young adult public in the novel Jack and Harry: No turning back, by Tony McKenna e Mervyn Davis (2005). The audiobook and printed versions of the novel will be the focus of analysis and will provide material for the evaluation of the factors that approximate (and at times distance) the novel from the yarn, such as the performance of the voice artist, the Australian actor David Tredinnick, the rhythm of the narrative, as well as the influence of the so-called “Australian tradition/legend”, which brings to the plot themes such as egalitarianism and mateship, the traditional institution of unconditional loyalty between travellers in the Australian outback. Some aspects of the adventure story as a literary formula will also be considered. KEYWORDS: Jack and Harry: No turning back; Tony McKenna and Mervyn Davis; yarn; folk literature; teen literature, Australia.
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(Re)mapping the journey back to a lost father: traveling back in time and place in Michael Ondaatje`s "Running in the family"

(Re)mapping the journey back to a lost father: traveling back in time and place in Michael Ondaatje`s "Running in the family"

The story begins with a personal version of the map of Sri Lanka, with few directions and information: the map is not complete, and it reminds one of treasure maps revealing only the spots leading to the treasure. It seems to intentionally disregard the other possible routes of the country; instead, it reveals the routes intended by the narrator. The narrative does not start with a regular map of Sri Lanka, found in any atlas, but with one from the inside of the narrator’s mind, a personal and private map to guide a personal and private journey. The map offers the first hint to the journey: as the story evolves, Sri Lanka is visited and showed according to the narrator’s desire and view. The narration is personal and evocative of the narrator’s ancestors. The way the narrator organizes the chapters also leads to the way he draws the map: the stories and the sequence in which they are told obey no chronology or order. They follow the needs of the narrator, ranging from public to private, from touristy to personal, from historical to emotional, from motherland to fatherland. By the end of the narrative, in the “Acknowledgements”, the writer explains his intention of telling the story his way; with the scattered pieces of information chosen and disposed in one direction. He then weaves the threads of his journey and life, departing from a previously selected, carefully scrambled and varied route to a fictional journey, towards the ultimate encounter with his father. It is evident that the narrator, despite writing about himself in a fictional way, needs the approval of those involved in the plot, as he apologizes for a possible disapproval of his method. Aware of the fictional tone of the narrative, Ondaatje’s brother says “You must get this book right… you can only write it once” (201).
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GnRH-Analoga und Add-back-Verfahren

GnRH-Analoga und Add-back-Verfahren

Zu den Goldstandards bei den Add-back-Verfahren zählen Kombinationen aus konjugierten equinen Estrogenen (0,3– 0,625 mg/d) und Medroxyprogesteronacetat (5 mg/d) [12] bzw. einer Estrogenapplikation von 0,625–2,25 mg/d plus NETA (5 mg/d) [8]. In letztgenannter Studie profitierten alle Gruppen unter Add-back-Therapie bezüglich der Vermeidung von Hitzewallungen und der Knochenprotektion. Eine Beson- derheit bestand in der Gruppe mit höher dosierten konjugier- ten, equinen Estrogenen (1,25 mg) im Vergleich zur Dosie- rung mit 0,625 mg pro Tag. Frauen mit höherer Dosierung brachen die Therapie häufiger ab, weil endometriosebedingte Schmerzen erneut auftraten. Diese Erkenntnis lässt den Schluss zu, dass mit höheren Estrogendosen das „therapeutische Fens- ter“ im Add-back-Verfahren nicht mehr gewährleistet und eine Wachstumsstimulation der Endometriose initiiert wird. Weitere Kombinationen aus GnRH-A und Add-back-Verfahren bieten sich an, allerdings liegen dazu noch keine Studien vor. Ultraniedrige Dosierungen von transdermalem Estradiol (14 mg/d) waren in der Lage, über 2 Jahre eine Knochenprotektion bei postmenopausalen Frauen zu gewährleisten [13]. Ob die Kombination dieser transdermalen Estradiolapplikation mit der intravaginalen Gabe natürlichen Progesterons (200 mg/d) sich bei prämenopausalen endometrioseerkrankten Frauen eig- net, bedarf der Überprüfung. Analoges gilt für Estradiol in der Dosis von 1 mg/d oral kombiniert mit Drospirenon (2 mg/d). Hier bestünde der Vorteil in der Estrogendosisreduktion und dem Einsatz eines Gestagens mit Zulassung zur Endometriose- therapie.
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Back to the edge: relative coordinate system for use-wear analysis

Back to the edge: relative coordinate system for use-wear analysis

The epoxy resin component (Epoxydharz L) was mixed with the hardener component (Härter S) in a 10:4 ratio by weight. Black pigment concentrate (Universal-Farbpaste, Schwarz), maximum 2% weight, was added to make the p r e p a r a t i o n m o r e v i s i b l e . T h i x o t r o p i c f i l l e r (Thixotropiermittel) was also added on demand to reduce viscosity. All components are manufactured by R&G Faserverbundwerkstoffe GmbH (Waldenbruch, Germany). The pot life of the entire preparation is up to 1.5 h, and the curing time is approximately 24 h. Resin drops were applied via a needle-point onto the flint surface under a Leica M420 stereo-microscope at low magnification (× 120–× 180). After about 30 min, 100 –200 μm diameter ceramic beads (SiLiBead Type ZY-S 0,1-0,2; Sigmund Lindner GmbH, Warmensteinach, Germany) were applied via a needle- point wetted with 2-propanol, although we realized later that the residual resin was enough for the needle-point to remain sticky to handle the beads without alcohol (see Online Resource 1). This 30 min delay was necessary to ensure that the beads would not sink into the resin pool. The beads were centered as precisely as possible in the resin pool.
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