Real-world agents, humans as well as animals, observe each other during interactions and choose their own actions taking the partners’ ongoing behaviour into account. Yet, classical game theory assumes that players act either strictly sequentially or strictly simultaneously without knowing each other’s current choices. To account for action visibility and provide a more realistic model of interactions under time constraints, we introduce a new game-theoretic setting called transparent games, where each player has a certain probability of observing the partner’s choice before deciding on its own action. By means of evolutionary simulations, we demonstrate that even a small probability of seeing the partner’s choice before one’s own decision substantially changes the evolutionary successful strategies. Action visibility enhances cooperation in an iterated coordination game, but reduces cooperation in a more competitive iterated Prisoner’s Dilemma. In both games, “Win–stay, lose–shift” and “Tit-for-tat” strategies are predominant for moderate transparency, while a “Leader-Follower” strategy emerges for high transparency. Our results have implications for studies of human and animal social behaviour, especially for the analysis of dyadic and group interactions. Humans and animals constantly make social decisions. Should an animal during group foraging or a human at the buffet try to obtain an attractive food item but risk a confrontation with a dominant conspecific, or is it better to opt for a less attractive but non-confrontational choice, especially when considering that the situation will repeat in the future? To model decision-making in such situations game theory is widely used. However, classic game theory assumes that agents act either at the same time, without knowing each other’s choices, or one after another. In contrast, humans and animals usually try to take the behaviour of their opponents and partners into account, to instantaneously adjust their own actions if possible. To provide a more realistic model of decision making in a social setting, we here introduce the concept of transparent games. It integrates the probability of observing the partner’s instantaneous actions into the game-theoretic framework of knowing previous choice outcomes. We find that such “transparency” has a direct influence on the emergence of cooperative behaviours in classic iterated games. The transparent games can contribute to a deeper understanding of social behaviour and decision-making of humans and animals. In sequential games players act one after another in a random or predefined order 39]. Howe actions , 53–55. psee strongly affects the evolutionary success of strategies. In particular, in the transparent i(A)CG even moderate psee helps to establish cooperative turn-taking, while high psee brings about a new successful strategy, Leader-Follower (L-F). For the transparent iPD we have shown that for psee > 0 the Generous tit-for-tat strategy is unsuccessful and Win–stay, lose–shift (WSLS) is an unquestionable evolutionary winner for 0 < psee ≤ 0.4. However, WSLS is not evolutionary stable  all strategies become quite unstable and cooperation is hard to establish /2 = 2.5, but is generally less susceptible to exploitation by defecting strategies. This explains the abrupt drop of cooperation in the transparent iPD with psee ≥ 0.4 for R = 3.0 (R > 3.2 (R > 3 > (T + P)/2 promotes mutual cooperation among memory-one strategies since it results in higher payoff than defecting a cooperator (resulting in a payoff T) followed by mutual defection (payoff P), which is a natural response of any cautious strategy like TFT or WSLS. Therefore the case R > 3.2 is perhaps less interesting than the classic payoff matrix with R = 3.The value of probability stablish . Finally R = 3.0 , while s(R > 3.2 . Note thR ≥ (T + P)/2. While the defecting player gets T = 5 in the first round, its payoff in the next round is P = 1, which makes the average payoff over two rounds less than or equal to the reward for cooperation R. Thus for the iPD with standard payoff R = 3 = (T + P)/2 WSLS players do not benefit from defecting their WSLS-partners already for the two-round horizon. (Note that for R < (T + P)/2 defection is effective against WSLS, which explains the low frequency of WSLS for R < 3 in psee = 0.5 against a partner with a pure L-F strategy  and has to choose between L-F and AllD strategies. In a single round using AllD is (strictly) better with probability p = 1/2 (probability of being a Follower). From the two-round-perspective using AllD is beneficial with p = 1/4 (the probability of being a Follower in both rounds). For n = 6 rounds, AllD is still better than L-F with p = 7/64 . In general, for any finite number n of rounds, there is a risk to suffer from using the L-F strategy instead of AllD, and the probability of this is given by nP/T⌉ is the integer part of nP/T and Although resulting in a lower payoff than explicit cooperation, L-F can be also seen as a cooperative strategy for iPD. While the choice of Leaders (defection) is entirely selfish, Followers “self-denyingly” cooperate with them. Importantly, the L-F strategy is not beneficial for some of the players using it in any finite perspective, which distinguishes this strategy from most cooperative strategies. Let us explain this point by comparing L-F with WSLS. In a game between two WSLS-players, neither benefits from unilaterally switching to defection even in a short term for The lack of stability in the transparent iPD renders the analysis of the strategy dynamics for this game non-trivial. Therefore we do not provide here an exhaustive description of strategies in iPD and content ourselves with general observations and explanations. An in-depth analysis of strategy dynamics in the transparent iPD will be provided elsewhere as a separate, more technical paper .psee . This prevalence of the L-F strategy can be explained as follows: in a group where the behaviour of each agent is visible to the others and can be correctly interpreted, group actions hinge upon agents initiating these actions. In both games these initiators are selfish, but see psee the similarities of the two games are less obvious. However, the Challenger strategy in i(A)CG follows the same principle of “Win–stay, lose–shift” as the predominant strategy WSLS in iPD, but with modified definitions of “win” and “lose”. For Challenger winning is associated with any outcome better than the minimal payoff corresponding to the mutual accommodation. Indeed, a Challenger accommodates until mutual accommodation takes place and then switches to insisting. Such behaviour is described as “modest WSLS” in [Despite the clear differences between the two games, predominant strategies evolving in iPD and i(A)CG have some striking similarities. First of all, in both games, L-F appears to be the most successful strategy for high WSLS” in , 58 and WSLS” in .psee ≥ 0.4, are partially based on taking turns and are similar to the Turn-Taker strategy in i(A)CG. The same holds to a lesser extent for the GTFT strategy.The third successful principle in the transparent iPD is “Tit-for-tat”, embodied in Generous tit-for-tat (GTFT), TFT and Firm-but-fair (FbF) strategies. This principle also works in both games since turn-taking in i(A)CG is nothing else but giving tit for tat. In particular, the TFT and FbF strategies, which occur frequently in iPD for psee makes sense if we understand psee as a species’ ability to signal intentions and to interpret these signals when trying to coordinate (or compete). The higher psee, the better (more probable) is the explicit coordination. This could mean that a high ability to explicitly coordinate actions leads to coordination based on observing the leader’s behaviour. In contrast, moderate coordination ability results in some form of turn-taking, while low ability leads to simple strategies of WSLS-type. In fact, an agent utilizing the WSLS principle does not even need to comprehend the existence of the second player, since WSLS “embodies an almost reflex-like response to the pay-off” [The success of specific strategies for different levels of pay-off” . The abiWhile we focused here on the iterated Prisoner’s Dilemma and on the specific formulation of iterative (Anti-)Coordination Game, the transparent games framework can be applied to treatment of other two-player, two-action transparent games. In particular, we have shown that the structure of the Nash equilibria for the Hawk-Dove and Leader games is identical to that of (Anti-)Coordination Game  of Player i to see the choice of the other player, In this study, we focus on iterated two-player (dyadic) two-action games: in every round both players choose one of two possible actions and get a payoff depending on the mutual choice according to the payoff matrix . A new gTo illustrate how transparent, simultaneous and sequential games differ, let us consider three scenarios for a Prisoner’s Dilemma (PD):If prisoners write their statements and put them into envelopes, this case is described by simultaneous PD.If prisoners are questioned in the same room in a random or pre-defined order, one after another, this case is described by sequential PD.Finally, in a case of a face-to-face interrogation where prisoners are allowed to answer the questions of prosecutors in any order  the transparent PD comes into play. Here prisoners are able to monitor each other and interpret inclinations of the partner in order to adjust their own choice accordingly.same action (cooperate) in PD, but complementary actions in (A)CG . In games of (A)CG type, one of the two coordinated choices is more beneficial for Player 1 , and the other for Player 2 , thus to achieve fair cooperation players should alternate between these two states.While the transparent setting can be used both in zero-sum and non-zero-sum games, here we concentrate on the latter class where players can cooperate to increase their joint payoff. We consider the transparent versions of two classic games, the PD and the (Anti-)Coordination Game ((A)CG). We have selected PD and (A)CG as representatives of two distinct types of symmetric non-zero-sum games , 31: maxS = 4 by insisting: when the second player knows that the partner insists, it is better to accommodate and get a payoff of T = 3, than to insist and get R = 2. In PD, however, defection is less beneficial if it can be discovered by the opponent and acted upon . Therefore, in PD most players prefer acting later: defectors to have a better chance of getting T = 5 for a successful defection, and cooperators to make sure that the partners are not defecting them. The only exception from this rule is the Leader-Follower strategy, but as we show in Another important difference between the two considered games is that in (A)CG a player benefits from acting before the partner, while in PD it is mostly preferable for a player to act after the partner. Indeed, in (A)CG the player acting first has good chances to get the maximal payoff of Consider a one-shot transparent game between Player 1 and Player 2 having strategies Let us provide two definitions that will be used throughout this section.Definition 1. Strategies s1 and s2 are said to form a Nash Equilibrium if neither player would benefit from unilaterally switching to another strategy, that is E ≥ E and E ≥ E for any alternative strategies r1 and r2 of Players 1 and 2, respectively.Definition 2. Let us denote Eij = E. Strategy s1 is said to dominate strategy s2 if E11 ≥ E21 and E12 ≥ E22. If both inequalities are strict, s1strictly dominatess2. Strategies s1 and s2 are said to be bistable when E11 > E21 and E12 < E22. Strategies s1 and s2co-exist when E11 < E21 and E12 > E22.Some intuition on these notions is provided below in subsection “Evolutionary dynamics of two strategies”. We refer to  for detaFor the sake of simplicity, we assume for the rest of this section that Here we assume that Lemma 1. In one-shot transparent PD with psee > 0 any strategy  with s2, s3 > 0 is dominated by strategies  and . The dominance of  is strict when s1 > 0, the dominance of  is strict when s1 < 1.Proof. Consider the strategies s1 = , s2 = . To show that s1 dominates s2, it is sufficient to demonstrate that E11 − E21 ≥ 0 and E12 − E22 ≥ 0. Two following inequalities can be inferred from  with 0 ≤ x ≤ 1 andProof. First we show that for any x, y satisfying  and  form a Nash Equilibrium. Assume that there exists a strategy , which provides a better payoff against  than . According to Lemma 1, expected payoff of a strategy  is not less than the payoff of . Now it remains to find the value of s1 maximizing the expected payoff E of . From  results in the same payoff P as the strategy , which proves that a pair of strategies ,  is an NE. If  is not an NE, since switching to  results in a better payoff.tisfying , strategtrategy s; s2; s3,z) or  with 0 ≤ z ≤ 1 and 0 < u < 1. In both cases switching to unconditional defection is preferable, which finishes the proof.Let us show that there are no further NE. Indeed, according to Lemma 1 if an alternative NE exists, it can only consist of strategies  strategy, a player gets pseeP + (1 − psee)T. However,  is dominated by a strategy  that cooperates when it does not see the choice of the partner and defects otherwise. This strategy, in turn is dominated by .The one-shot transparent PD has two important differences from the classic game. First, the unconditional defection  dominates the cooperative strategy  only for x; 0) with x > 0 retaining the same payoff. This, together with Proposition 3 below, makes possible a kind of evolutionary cycle:  →  ↔  → ,  → .Second, in transparent PD unconditional defection  is not evolutionary stable as players can switch to  and  have the following relations:if condition  dominates ;ondition  and the if neither  dominates ; neither  nor 3)  if neithif . To prove that  dominates  we need to show that Player 2 has no incentive to switch to  and that Player 1, on the contrary, would get higher payoff if using . The latter statement follows from Proposition 2. To show that the former also takes place we simply write down expected payoffs E11 and E21 of strategies  and  when playing against :11 ≤ E21 holds whenever inequality  and Player 2—strategy  and “defectors” s2 =  since they dominate all other strategies. Note that the probability From Lemma 1, we know that it is sufficient to consider two strategies: “cooperators” Then the expected payoff matrix for these two strategies in the one-shot transparent PD is given bySince s1 dominates for cooperative strategy s1 and s2 are bistable for E11 > E21, that is fors2 dominates otherwise.defecting strategy s1 acting with a delay has a chance to win over defectors if it can see their actions with probability For the standard Prisoner’s Dilemma payoff matrix , inequalRecall  that in Proposition 4. Consider one-shot transparent (A)CG between Players 1 and 2 with probabilities to see the choice of the partnerrespectively. Letthen this game has the following pure strategy NE.Player 1 uses strategy , Player 2 uses strategy —forPlayer 1 uses strategy , Player 2 uses strategy —forBoth players use strategy —when (is not satisfied. 1)—when  is not sAdditionally, if inequality , Player 2 uses strategy  when  when  when  holds, a 1) when  does notRemark 1. For the correct interpretation of Proposition 4 it is important that inequality CG we have:Lemma 5. In one-shot transparent (A)CG any strategy  is dominated by strategies  and . The dominance of  is strict when s1 > 0, the dominance of  is strict when s1 < 1.R < T and P < S. Otherwise the proof is identical to the proof of Lemma 1.The proof is based on the fact that for the (A)CG game hold inequalities Lemma 6. In one-shot transparent (A)CG, when Player 1 uses strategy , the best response for Player 2 is to use strategy  forand to use  otherwise.Proof. By Lemma 5 the best response for Player 2 is a strategy  with 0 ≤ s1 ≤ 1. When Player 2 uses this strategy against , the expected payoff of Player 2 is given bys1 and is maximized by s1 = 0 ifs1 = 1 otherwise. Inequality (1)(T-R)<0and by sequality , which cUsing Lemmas 5 and 6, we can now compute NE for the one-shot transparent (A)CG:Proof. Pure strategy NEs are obtained immediately from Lemma 6. To compute the mixed-strategy NE, recall that Player 1 achieves it when the expected payoff obtained by Player 2 for insisting and accommodating is equal:given in .Corollary 7. Consider one-shot transparent (A)CG with S = 4, T = 3, R = 2, P = 1, where both players have equal probabilities pseeto see the choice of the partner. In this game there are three NE for psee < 1/3: (a) Player 1 uses strategy , Player 2 uses strategy ; (b) vice versa; (c) both players use strategy , withFor psee ≥ 1/3,  is the only NE.S > T > R > P, this result is easily generalized to a wider class of (anti-)coordination games including several other important games, such as Hawk-Dove and Leader. Together with PD and (A)CG, Hawk-Dove and Leader form the set of two-player two-action games where players have a conflict of interests [While we consider in Proposition 4 only the (A)CG game for which nterests . Hawk-Donterests , 80–82. nterests , (A)CG, Proposition 8. Consider a general one-shot transparent game between Players 1 and 2 with probabilities to see the choice of the partnersatisfyingIf the payoff matrix of the game satisfies inequalities S > T > R and S > P, then the Nash equilibria (NE) of this game is described by Proposition 4. Namely, when , Player 2 uses strategy  when  when  when  holds, a 1) when  does notProof. The proof coincides with the proof of Proposition 4. Indeed, Lemma 5 holds for any game with T > R and S > P. Lemma 6 holds whenever T > R and S > R. Finally, NE are described in Proposition 4 for the case S > T.S > P > T > R. To get the classic notation for this game, one needs to replace in Two classical games satisfy conditions of Proposition 8. The first is the “Hawk-Dove” game, where S > T > P > R. This game is similar to the (A)CG game formulated as insisting on own preference or accommodating the other, with the difference that here if both players insist it is detrimental for both, so it is better to accommodate, however the insisting player receives maximal reward if the other player accommodates. An example of a Leader game payoff matrix can be obtained from that in P = 2, R = 1, while leaving S = 4, T = 3.The second relevant game is Leader, described by The payoff matrices of these games are illustrated in the For the analysis of iterated games we use the techniques described in , 24. Sini is represented by a vector k enumerates the twelve (4 × 3) different combinations of previous outcome and the current probability of choice. The entries 1 (“Cooperate” in iPD and “Insist” in i(A)CG, see A strategy without memory in transparent games is described by a three-element vector. A memory-one strategy additionally conditions current choice upon the outcome of the previous round of the game. Since there are 4 = 2 × 2 possible outcomes, a memory-one strategy for a player type 1 without seeing the partner’s choice, given that in the previous round the joint choice of the player and the partner was A1A1, A1A2, A2A1, and A2A2 respectively ;1, seeing the partner selecting A1 and given the outcome of the previous round (as before).1, seeing the partner selecting A2 and given the outcome of the previous round.2 are given by Probabilities to select At = 1, 2, … the population consists of n(t) player types defined by their strategies xi(t) in the population, i to see the choice of a partner from type j is given by i and j, but in this section we use the general notation).Consider an infinite population of players evolving in generations. For any generation i playing an infinitely long iterated game against a player from type j. Since both players use memory-one strategies, this game can be formalized as a Markov chain with states being the mutual choices of the two players and a transition matrix M given byM0, M1 and M2 describe the cases when neither player sees the choice of the partner, Player 1 sees the choice of the partner before making own choice, and Player 2 sees the choice of the partner, respectively. These matrices are given byi when playing against type j is given by the expected payoff Eij, defined byR, S, T, P are the entries of the payoff matrix CG, see yR, yS, yT, yP represent the probabilities of getting to the states associated with the corresponding payoffs by playing si against sj. This vector is computed as a unique left-hand eigenvector of matrix M associated with eigenvalue one [Consider a player from type pseejiM2,where thi is encoded by its fitness fi(t): if type i has higher fitness than the average fitness of the population xi(t) increases with time, otherwise xi(t) decreases and the type is dying out. This evolutionary process is formalized by the replicator dynamics equation, which in discrete time takes the formfi(t) is computed as the average payoff for a player of type i when playing against the current population:ij is given by , s2 =   = x2(1) = 0.5. That is, the first type plays the “Win–stay, lose–shift” (WSLS) strategy, and the second type  always defects (uses the AllD strategy). We set psee ≤ 0.5. Given psee we can compute a transition matrix of the game using  > f1(t) for any 0 < x1(t), x2(t) < 1, the AllD-players take over the whole population after several generations. Dynamics of the type frequencies xi(t) computed using . In this case one says that AllD dominates WSLS and can invade it for any x1(1).To provide an example of evolutionary dynamics and introduce some useful notation, we consider a population consisting of two types playing iPD with strategies: me using  and thenij using . For insed using . Note thpsee, the population dynamics changes. While for psee = 0.2 AllD still takes over the population, for psee = 0.4 WSLS wins (psee = 0.4:f1(t) > f2(t) for 0 ≤ x2(t) ≤ 0.5 ≤ x1(t) ≤ 0, which explains the observed dynamics. Note that here E11 > E21, while E12 < E22, that is when playing with WSLS- and AllD-players alike partners of the same type win more than partners of a different type. In this case one says that WSLS and AllD are bistable and there is an unstable equilibrium fraction of WSLS players given byhi an invasion threshold for type i, since this type takes over the whole population for xi(t) > hi, but dies out for xi(t) < hi. To illustrate this concept, we plot in h1 as a function of psee for WSLS type playing against AllD.As we increase SLS wins . This cacoexistence, which takes place when E11 < E21, E12 > E22, that is when playing against a player of any type is less beneficial for a partner of the same type than for a partner of a different type. In this case the fraction of a type given by (x1(t) increases for x1(t) < h1, but decreases for x1(t) > h1.The third possible case of two-types dynamics is Theoretical analysis of the strategies in repeated transparent games is complicated due to the many dimensions of the strategy space, which motivates using of evolutionary simulations. For this we adopt the methods described in , 24. We n(1) = 5, x1(1) = … = x5(1) = 0.2. Following [k = 1, …, 12 for each player type i are randomly drawn from the distribution with U-shaped probability density, favouring probability values around 0 and 1:y ∈ . Additionally, we require ε = 0.001 accounts for the minimal possible error in the strategies [psee = 0.0, 0.1, …, 0.5.Each run of simulations starts with five player types having equal initial frequencies: ollowing , strategrategies . The facrategies , 86. We xi(t) change according to the replicator xi(t) < χ, the type is assumed to die out and is removed from the population (share xi(t) is distributed proportionally among the remaining types); we follow [χ = 0.001. Occasionally (every 100 generations on average to avoid strong synchronization), new types are entered in the population. The strategies for the new types are drawn from (xi(t0) = 1.1χ [The frequencies of strategies e follow , 24 in tawn from  and the S1 Note(PDF)Click here for additional data file.S2 Note(PDF)Click here for additional data file.S1 Figpsee ≥ 0.4 is especially noticeable. Indeed, in highly transparent iPD any strategy is sufficiently “predictable”, which allows a best-response strategy to replace it in a population. Such best-response strategies can be generally weak and short-living, see for example treacherous WSLS described in psee ≥ 0.4 in i(A)CG, which reflects the fact that Leader-Follower strategy becomes evolutionary stable for high transparency.(A) for iterated Prisoner’s Dilemma (iPD) and (B) for iterated (Anti-)Coordination Game (i(A)CG). The central mark indicates the median, and the bottom and top edges of the box indicate the 25th and 75th percentiles, respectively. The whiskers extend to the most extreme data points not considered outliers, and the outliers are plotted individually using the ‘+’ symbol. The higher total shares of the types are, the more stable the dynamics in the population is. While stability varies with transparency for both games, the drop of stability in iPD for (TIF)Click here for additional data file.S2 Fig(TIF)Click here for additional data file.


Vehicle-to-Everything (V2X) requires high-speed communication and high-level security. However, as the number of connected devices increases exponentially, communication networks are suffering from huge traffic and various security issues. It is well known that performance and security of network equipment significantly depends on the packet classification algorithm because it is one of the most fundamental packet processing functions. Thus, the algorithm should run fast even with the huge set of packet processing rules. Unfortunately, previous packet classification algorithms have focused on the processing speed only, failing to be scalable with the rule-set size. In this paper, we propose a new packet classification approach balancing classification speed and scalability. It can be applied to most decision tree-based packet classification algorithms such as HyperCuts and EffiCuts. It determines partitioning fields considering the rule duplication explicitly, which makes the algorithm memory-effective. In addition, the proposed approach reduces the decision tree size substantially with the minimal sacrifice of classification performance. As a result, we can attain high-speed packet classification and scalability simultaneously, which is very essential for latest services such as V2X and Internet-of-Things (IoT). Internet traffic is increasing exponentially every year with the advent of new services such as Internet-of-Things (IoT) and Vehicle-to-Everything V2X). The number of connected vehicles is expected to reach 125 million by 2022 [X. The nuThe packet classification algorithm is not only necessary for security function, but also essential for basic packet processing in network equipment . For theTo resolve this issue, various packet classification algorithms have been proposed in previous literature ,5,6. TheUnfortunately, there is a common tradeoff between search table size and packet classification speed. For example, our approach can improve the classification speed significantly but also suffers from a huge table size. Thus, when designing a packet classification algorithm, a popular guideline is to improve the classification speed by using more memory. Most existing algorithms are based on such an approach and do not satisfy high classification speed and small memory usage at the same time.Today a decision tree, which is a well-known searching algorithm, is widely used in packet classification algorithms. The algorithms construct a decision tree by dividing a rule-set into multiple sub-partitions repeatedly, according to an internal criterion that determines the partitioning fields and the partitioning size. When a packet arrives, the algorithms search through the decision tree, and find a matching rule. Unfortunately, although the decision tree is very popular, we cannot construct the optimal decision tree in the computationally efficient manner. Indeed, even the two-means clustering, i.e., the simplest partitioning problem of dividing a set into two partitions is NP-hard ,15. ManyIn packet classification algorithms using the decision tree, rules in a node are partitioned into multiple subsets of the rules and each subset is stored in a child node. If a rule satisfies conditions of more than one partition, it is stored in multiple child nodes. In that case, we say the rule is duplicated. If the rule duplication happens frequently, we consume more memory space for the decision tree because the same rule is copied several times in the memory. Hence, we should be careful to choose a partitioning criterion in order to minimize the rule duplication. In this paper, we propose a new partitioning algorithm for decision tree-based classification algorithm to minimize rule duplication significantly. To this end, we define a partitioning preference coefficient for each partitioning field. The value represents how uniformly rules can be distributed in the node and how efficiently the rule duplication can be avoided, when each field is chosen as the partitioning criterion. We define the coefficient as simply as possible since the computational burden can degrade the partitioning performance. This algorithm can be applied for most decision tree-based packet classification algorithms and can greatly improve their scalability without sacrificing classification performance. Since our algorithm improves the common partitioning procedure of decision tree-based algorithms, it can be applied for most decision tree-based algorithms without significant modification.First, we propose a new partitioning field selection algorithm that finds the optimal partitioning field using the number of unique matching ranges and the number of wildcards. As far as we know, it is the first approach to use the concept of wildcards based on the matching range of each node, so the algorithm can minimize duplicated rules compared to existing ones.Second, we also propose a new partitioning number per field decision algorithm that chooses two partitioning fields through the partitioning field selection algorithm on each node, and finds the number of partitions based on the selected fields to minimize rule duplication. Since it considers only two fields to choose the partitioning number in contrast to existing algorithms using multiple fields, it is fast without the performance degradation.Our contribution is twofold as follows:We organize the remainder of this paper as follows. We briefly explain the related works in In this section, we explain two famous packet classification algorithms based on the decision tree, i.e., HyperCuts  and EffiHyperCuts extends the previous HiCuts algorithm . HoweverBefore describing HyperCuts in detail, we explain the meaning of “the number of unique matching ranges”. We consider the rule-set in When generating a decision tree, HyperCuts needs two configuration parameters, “binth” and “space factor”, where “binth” is the maximum number of rules stored in the leaf node and “space factor” is the maximum number of rule duplications allowed in each partitioning operation. To satisfy the constraints, HyperCuts builds the decision tree as follows. At first, it partitions a root node that contains the entire rule-set, based on one or more fields. As a result, we obtain multiple subsets of rules, and to store each subset, corresponding child nodes are generated. This procedure repeats until all the leaf nodes satisfy the constraints. During the procedure, HyperCuts selects the partitioning fields and the number of partitions for each field. We describe each step in detail. k-th field, where HyperCuts should choose the effective partitioning fields prior to conducting partitioning. However, it is not easy to select optimal partitioning fields. When the number of partitioning fields is large, more subsets (and accordingly more child nodes) are generated. Hence, the height of the decision tree decreases, and thus, classification performance improves. Instead, memory usage increases since each rule can be duplicated to multiple child nodes. We should choose an appropriate number of partitioning fields to balance search performance and memory requirement simultaneously. For this, HyperCuts selects one or more fields for partitioning, considering the number of unique matching ranges. For illustration, we define the following notations.In HyperCuts, all fields satisfying Equation (1) are chosen as partitioning fields:For example, if we count unique matching ranges for each field in After choosing partitioning fields, HyperCuts determines how many child nodes it should generate by partitioning the current node. The number of partitions affects memory requirement as well as classification speed. Unfortunately, it is inefficient and almost impossible to look over all the possible combinations of fields. Alternatively, HyperCuts calculates the number of near-optimal partitions, considering each field one-by-one. To describe the approach, we define the following symbols.Now, the maximum Since HyperCuts conducts partitioning for multiple fields, the total number of partitions is When more than one field has the same partition number, the algorithm prefers the field with the smallest matching range. For the rule-set of EffiCuts aims at cutting the memory requirement down because it is a critical problem of HyperCuts in practice. EffiCuts builds a decision tree based on HyperCuts. However, differently from HyperCuts, it creates multiple decision trees for each subset of rules, called “category”. This approach reduces the rule duplication significantly.We now explain two important operations of EffiCuts, i.e., tree splitting and tree merging. We here assume that each rule consists of 5-tuple of source IP, destination IP, source port, destination port, and protocol.EffiCuts constructs multiple decision trees, contrary to HyperCuts. To this end, the algorithm splits the entire rule-set into categories in advance, where a “category” means a group of rules with similar matching ranges for each field. Specifically, EffiCuts defines the wildcard field for each rule using the following notations:Category 1: rules with four wildcard fieldsCategory 2: rules with three wildcard fieldsCategory 3: rules with two wildcard fieldsCategory 4: rules with one or zero wildcard fieldThat is, the When each rule consists of 5-tuple, we can divide Category 1 further into five subcategories; all fields are wildcard except for source IP, or destination IP, or source port, or destination port, or protocol. Similarly, we can define ten subcategories for Categories 2 and 3 and six subcategories for Category 4. Conclusively, we classify the rules of If we create decision trees for each subcategory using EffiCuts, memory usage decreases drastically since rule duplication is minimized. However, we should look up all the decision trees for classification of each packet, which deteriorates the search performance. Thus, we need to limit the total size of decision trees within a certain number. In EffiCuts, we can reduce the number of decision trees by merging multiple subcategories into one. Unfortunately, the merge can lead to rule duplication. To minimize this negative effect, EffiCuts combines similar subcategories only, specifically the subcategories different in one wildcard field at most. For example, in EffiCuts greatly reduces the rule duplication and thus also the memory requirement, compared to HyperCuts. However, EffiCuts is known to provide slower packet classification speed than HyperCuts since there are many decision trees to look over for each packet.In this section, we explain our partitioning algorithm that minimizes rule duplication. The proposed algorithm can improve both the memory requirement and the packet classification performance effectively by solving the limitation of existing decision tree algorithms. For an easy explanation of the proposed algorithm, we assume that rules consist of 5-tuple such as source IP, destination IP, source port, destination port, and protocol.In a decision tree algorithm, if we use more fields for partitioning a rule-set, the depth of the final decision tree is generally reduced, thereby improving the packet classification performance. However, this partitioning process does not use memory efficiently due to significantly generated redundant nodes. HyperCuts selects the partitioning field based on the number of unique matching ranges for each field in order to balance packet classification performance and memory usage. Unfortunately, this approach still has the following problems.First, it does not consider wildcard fields in partitioning at all. HyperCuts internally adopts the equal-interval partitioning. That is, if the algorithm selects a field with a large number of unique matching ranges according to Equation (1) but it is unfortunately a wildcard field, many rules are duplicated during the partitioning process. Thus, in this case, it should consider wildcard fields and select a partitioning field to decrease the rule duplication and the memory requirement.Second, HyperCuts does not determine the optimal number of partitions. If two partitioning fields lead to the same number of partitions, the number of partitions for a field with smaller matching range is reduced by half according to the internal algorithm. However, it can be better to choose a field with larger matching range in reducing the number of partitions. In conclusion, the performance of the final decision tree severely depends on the partitioning field selection algorithm and the number of partitions for the field. We can improve the ratio of memory requirement to packet classification performance by elaborately choosing the partitioning fields as well as the number of partitions.We now describe the proposed partitioning algorithm using wildcards in detail. Our algorithm consists of two sub-algorithms, the partitioning field selection algorithm and the partitioning number per field decision algorithm. We call the proposed algorithm Selection Based on Wildcards (SBW) for simplicity.We should determine the wildcard field for each node to be partitioned, in order to select the partitioning field minimizing the rule duplication. We recursively choose the partitioning node until the decision tree is completed, thereby considering the matching range of the current node. For example, let us assume that the current node has a partitioned matching range for Field 1 as , where the original full range of the field is . If we make partitions for the node based on Field 1 again, then we should consider the full matching range as  instead of .However, Equation (4) of EffiCuts determines if a field is a wildcard or not using the full matching range of the field. For example, In the child node of the root node, the wildcard field of each rule can change. We consider Child 1, that is, one of eight child nodes created by partitioning the root node of The original wildcard field is defined only for a root node, but we extend the concept of wildcard field to each child node also in a decision tree. To define the extended concept of wildcard, we denote all notations as follows:We now define the following condition for the Equation (5) considers the matching range for wildcard decision in the current node. However, it causes additional partitioning time since it calculates Equation (5) in every node during partitioning, until the final decision tree is completed.The number of unique ranges is used as an indicator of whether rules are evenly distributed to child nodes or not. As the number increases, the rules tend to be uniformly distributed to the child nodes without significant rule duplication. For example, if there is only one range, the rules can be duplicated and distributed to all new child nodes. Then, the memory usage increases and the packet classification speed decreases.A wildcard is also an indicator of the rule duplication degree. If there are many rules for which the selected partitioning field is a wildcard, it causes many rule duplications. It significantly increases the memory requirement. If such fields are frequently chosen as a partitioning field, the final decision tree will be huge. Therefore, the selected partitioning field should have rules without wildcards to minimize the rule duplication. With these observations, our proposed algorithm selects a field with a small number of wildcards and a large number of unique matching ranges as a partitioning field.The proposed algorithm can be described as follows. First, the number of unique matching ranges and the number of wildcards are calculated for each field of every rule stored in the node. Then, the average values of the numbers for all fields are obtained. Finally, the partitioning preference coefficient is calculated by using these average values. The partitioning preference coefficient for the Existing algorithms such as HyperCuts and EffiCuts select the partitioning field using the number of unique ranges as in Equation (1). However, the condition does not consider the number of wildcards at all, which causes considerable rule duplication problems. On the other hand, the proposed algorithm computes The existing algorithm such as HyperCuts or EffiCuts can theoretically choose multiple partitioning fields, even more than two, in contrast to ours. Partitioning using more fields generally shows the better partitioning result. However, we should note that in practice, the existing algorithm usually selects only two or fewer fields. This property guarantees that our algorithm does not achieve lower performance compared to the existing solutions although it just chooses two fields. When we calculate After we choose two partitioning fields through the above-described algorithm, we should determine the number of partitions based on the selected fields. The existing algorithm, HyperCuts, initially determines the number of partitions for each field through Equation (2). After that, it determines the most efficient partitioning number by considering the combination of partitioning fields through Equation (3). If the numbers of partitioning fields are the same, the proposed algorithm tries to reduce the number of partitioning fields with a larger matching range as well as a field with a smaller matching range using Equation (3), in contrast to the existing algorithm. Then, we separately conduct partitioning for the two partitioning fields in advance on the current node, and select the most efficient number of partitions that minimizes rule duplication.Compared to HyperCuts and EffiCuts, our proposed algorithm has unique features such as high flexibility, low memory requirement for building and maintaining decision trees, fast building speed, and fast classification performance.The proposed algorithm adopts a new partitioning field selection algorithm that minimizes the memory requirement in the partitioning process of HyperCuts. Therefore, it can be easily applied to partitioning process of all packet classification algorithms based on HyperCuts. For example, EffiCuts classifies a rule-set into sub-rule-sets according to the number of wildcard fields and then partitions each sub-rule-set in the same way as HyperCuts. Therefore, the proposed algorithm can be combined into the partitioning process of EffiCuts. In this case, although EffiCuts can reduce memory requirement significantly compared to HyperCuts, our algorithm can reduce the memory requirement more than EffiCuts.As mentioned earlier, the existing algorithm does not consider wildcards at all in selecting partitioning fields. However, rule duplication is a serious problem caused by wildcard field and the memory requirement increases proportionally to the number of wildcard fields.The proposed algorithm considers both the number of unique matching ranges and the number of wildcards to reduce the memory requirement. It chooses fields with the smallest wildcard number as partitioning field by assigning more weight to the number of wildcards than the number of the unique matching ranges. This minimizes the rule duplication for each partitioning process, which can significantly reduce the decision tree size and the memory requirement for building the tree.One of the goals of the proposed algorithm is also to build the decision tree in a short time. To generate a decision tree fast, the partitioning algorithm should minimize the size of rules in the generated child nodes for each partitioning. The proposed algorithm finds the most efficient partitioning number by partitioning the given rule-set in advance according to the obtained partitioning number. Such an approach can increase the partitioning time more than the original partitioning algorithm. However, it can perform more efficient partitioning, therefore, generating child nodes with very small number of rules. Although it takes a longer time in the partitioning process, the total time for generating the final decision tree can be reduced.The decision tree-based packet classification algorithm can easily trade off the memory requirement and the packet classification performance using “binth” and “space factor” parameters. Accordingly, if the memory requirement is increased, the classification performance can be improved by adjusting the parameters. The proposed approach greatly reduces the memory requirement, i.e., just 1/5 compared to EffiCuts, while maintaining the classification performance almost the same as the original algorithm. It means that the packet classification performance can be further improved by increasing the memory requirement until it reaches to the original requirement size through adjusting the parameters.Our proposed algorithm can be used with various classification algorithms based on decision tree to improve scalability in terms of supportable rule-set size. In this section, we apply our algorithm to HyperCuts and EffiCuts, which are well known for high classification performance and high scalability, and compare the performances before and after applying our algorithm. Since HyperCuts is one of the fastest classifications and EffiCuts is one of the most memory efficient classification algorithms among decision tree-based ones, we choose them as target algorithms to be applied with our SBW. For performance evaluation, we use three rule-sets, i.e. Access Control List (ACL), Firewall (FW), and IP Chain (IPC), generated by ClassBench . For eac• Memory requirement per ruleIt is the memory space required for a single rule. This metric is important for scalability of a packet classification algorithm with the rule-set size. These days, the rule-set size installed in a network equipment is increasing exponentially. Scalability is one of the most significant features of the packet classification algorithms. The required memory size per rule should be constant or decrease as the rule-set size increases, to support large-scale rule-sets.• Packet classification performanceWe measure the packet classification performance by the memory size accessed for packet classification procedure, because it is a bottleneck of the classification performance. The classification algorithm extracts key values from the head of each packet, and recursively searches the appropriate child node by comparing the keys with the matching condition of the traversing node in a decision tree. The search procedure stops when it reaches a leaf node. Then, the algorithm compares the keys with each rule stored in the leaf node. We measure the accessed memory size in bytes to accurately estimating the performance. For precise performance evaluation and analysis, we measure both the average and the worst performances. Average classification performance shows the overall performance of network equipment. On the other hand, the worst-case performance determines the specification of network equipment. • Table building timeTable building time refers to the time required to generate the final decision tree. We rebuild the decision tree whenever a rule changes. Even when the rule changes frequently, the packet classification algorithm should build the search table fast enough to satisfy the requirements of services such as V2X.Since SBW focuses on minimizing duplicated rules, HyperCuts or EffiCuts with SBW can be improved significantly in terms of memory requirement and building time, essential metrics to support V2X services in SDNs. Although the trade-off relation between classification speed and memory requirement exists, we can see that our approach can effectively minimize the side-effects of SBW, so we can have only marginally decreased classifciation performance. From the experiments, we confirm that we can obtain many advantages using SBW for existing algorithms.In this paper, we have proposed a new partitioning algorithm to resolve the high memory requirement and low scalability for existing packet classification algorithms. Differently from partitioning algorithms of the decision tree-based classification algorithms, we exploit not only the number of unique range elements but also the number of wildcard fields in the rule partitioning. Our algorithm selects a partitioning field that minimizes the rule duplication, by weighting the number of wildcard fields more than the number of unique ranges. For the field chosen, we determine the optimal number of partitions at the current node. Repeating this procedure, we construct a decision tree consuming the minimal memory space. We observe that existing packet classification algorithms with our algorithm outperforms them without ours in various scenarios. In some cases, search time can increase slightly but with significantly reduced memory usage. When we use the same amount of memory by adjusting the parameters such as “binth” and “space factor”, search performance improves highly. Therefore, we conclude that the proposed scheme attains the high-speed packet classification while supporting a large size rule-set simultaneously.


The androgen receptor (AR) is expressed in the majority of breast cancers and across the main breast cancer subtypes. Despite the high frequency of AR expression in breast cancer its appraisal remains controversial because its role is complex, dependent on the hormonal milieu. The aim of the current study was to investigate the frequency of AR and ER positive CETCs in breast cancer patients.The number of vital CETCs was determined from blood of 66 patients suffering from breast cancer and the expression of AR and ER on these cells was investigated using the maintrac method.Numbers of CETCs/mL blood were significantly higher in patients with advanced disease as compared to patients with early stage disease. The fraction of AR positive CETCs was significantly higher than the fraction of ER positive CETCs . Patients with positive lymph nodes had less AR positive CETCs as compared to patients with negative lymph node status. The AR:ER ratio was higher in patients receiving tamoxifen therapy as compared to patients without tamoxifen therapy whereas treatment with aromatase inhibitor had no influence on AR:ER ratio.The ratio of AR to ER positive CETCs, obviously, is influenced by endocrine therapy, more specifically therapy with tamoxifen. Since AR expression seems to be one of the possible mechanism of resistance to endocrine therapy this may provide a new biomarker to select patients who might benefit from combination treatment of ER and AR inhibitors. The biology of the androgen receptor (AR) and its therapeutic importance have been investigated extensively in prostate cancer . HoweverPeripheral blood (7.5 mL) from 66 patients with breast cancer in different stages of disease was drawn into normal blood count tubes with ethylenediaminetetraacetic acid (EDTA) as an anticoagulant and processed within 48 h of collection. The sampling of peripheral blood was carried-out 6–12 weeks after end of standard therapy . In patients with local or distant recurrence the blood was collected prior to treatment of recurrent disease. In parallel, control blood samples were collected from 15 healthy female and male donors aged 20–40 years. The study was conducted in accordance with Good Clinical Practice Guidelines and the declaration of Helsinki.® approach was used as reported previously [7 cells/100 µL cell suspension were added and incubated for 15 min in cold. The corresponding isotype control for EpCAM  was used at the same final concentration. The samples were subsequently diluted with 430 µL PBS-EDTA. A defined volume of the cell suspension and propidium iodide (PI)  was transferred to wells of ELISA plates . Analysis of red and green fluorescence of the cells was performed using a Fluorescence Scanning Microscope, ScanR, , enabling detection and relocation of cells for visual examination of EpCAM positive cells. For data analysis we used the ScanR Analysis software . Vital CETCs were defined as EpCAM-positive cells, with intact morphology lacking in nuclear PI staining and, only these cells were counted. We used fluorospheres  for daily verification of optical components and detectors of the microscope, which are required to ensure the consistent analysis of samples.For CETC enumeration and further characterization the maintraceviously . Brieflyl-glutamine  and 10% FBS. Cells were maintained at 37 °C in 5% CO2. For immunofluorescence analysis cells were detached from cell culture flasks using StemPro® Accutase® Cell Dissociation Reagent , washed and stained for AR or ER with the same protocol as patients’ samples.For the AR staining Sk-Br-3 (data not shown) and MCF-7 cell lines were used as positive controls and the SW-620 cell line as a negative control Fig. . For the® approach. For AR expression analysis we used an anti-human AR phycoerythrin (PE)-conjugated antibody  at a final concentration of 0.12 µg/mL and for ER we used an anti-human ER-PE conjugated antibody  at a final concentration of up to 107 cells/100 µL cell suspension. The corresponding isotype controls for AR  and ER  were used at the same final concentration. Finally, cells were visually inspected looking for a green and red surface staining, but also a well-preserved nucleus. For excluding expression of AR and ER on hematopoietic cells we additionally performed staining with EpCAM–FITC, AR–PE/ER–PE and CD45-Pacific blue antibodies (data not shown). The results for AR and ER were calculated as percentage of total number of CETCs.The analyses of AR Fig. a and ER Statistical analysis was performed using the software programs SigmaPlot version 13.0  for Windows. Comparisons between the variables were performed with the Student t test (dichotomous variables) or ANOVA (variables with more than two categories), taking into account the possibility of using nonparametric tests. The correlation was calculated with the Pearson or Spearman rank correlation coefficient. Receiver operating characteristic (ROC) curve was used to find the optimal cut-off point of CETC counts. The optimal cut-off point was determined by choosing the CETC count with the highest sum of sensitivity and specificity regarding to the stage of disease. Area under curve (AUC) analysis was applied to demonstrate the performance for better distinguishing patients in early and advanced stages of disease. The significance level was P < 0.05.The patient characteristics according to AR and ER expression are shown in Table ® method, an approach designed to minimize cell loss during the labeling and analysis process we were one of the first who could detect circulating tumor cells also in non-metastatic patients. Cell numbers could be monitored during treatment and we could show that an increase in the number of CETCs during chemotherapy correlates with an unfavorable prognosis [® approach the number of CETCs from the peripheral blood of patients with solid tumors detected is higher than that detected with other methods in both, early and advanced stage of disease [® method leads to a massive destruction of the tumor cells and also to a heavy cell loss [The detection of tumor cells circulating in the peripheral blood of metastatic cancer patients has been associated with both metastatic disease and a higher risk of progression . With thrognosis . Similarrognosis . Using t disease . This isell loss . Howeverell loss .In primary disease the number of CETCs was significantly related to the stage of disease. Our results indicate that patients with higher CETC counts have a more advanced stage of disease than patients with lower CETC counts. The AUC to distinguish between early and advanced stage with the CETC count was 0.74 with a high sensitivity and specificity. Thus, the CETC count in the peripheral blood is predictive for the severity of cancer disease. Our results are in agreement with the results of Maestro et al.  who usedDefinition of triple negative breast cancers (TNBC) is the absence of expression for ER and PR and absence of overexpression for HER2 by immunohistochemistry (IHC). It is well known that TNBC patients have more frequently axillary lymph node involvement and a shorter overall survival. Due to the lack of a receptor target chemo- and radiotherapy represent the only option for the treatment of TNBC . In the Our results in hormone receptor positive breast cancer are in agreement with the results from xenografts from cell lines reported by D’Amato et al. . StatistIn conclusion, with the maintrac platform we are able to identify CETCs in patients with breast cancer and to determine AR expression on those cells. Results from our study suggest that AR expression detected on CETC has capability to be a biomarker for identifying patients who might develop tamoxifen resistance. This needs to be clinically validated.


Heart failure (HF) has become increasingly common within the elderly population, decreasing their survival and overall quality of life. In fact, despite the improvements in treatment, many elderly people suffer from cardiac dysfunction  that are much more common in an older fragile heart. Since β-adrenergic receptor (β-AR) signaling is abnormal in failing as well as aged hearts, this pathway is an effective diagnostic and therapeutic target. Both HF and aging are characterized by activation/hyperactivity of various neurohormonal pathways, the most important of which is the sympathetic nervous system (SNS). SNS hyperactivity is initially a compensatory mechanism to stimulate contractility and maintain cardiac output. Unfortunately, this chronic stimulation becomes detrimental and causes decreased cardiac function as well as reduced inotropic reserve due to a decrease in cardiac β-ARs responsiveness. Therapies which  restore β-ARs responsiveness can ameliorate cardiac performance and outcomes during HF, particularly in older patients. In this review, we will discuss physiological β-adrenergic signaling and its alterations in both HF and aging as well as the potential clinical application of targeting β-adrenergic signaling in these disease processes. Heart failure (HF) is a leading cause of morbidity and mortality in western countries. Particularly, HF prevalence has increased to 6.5 million in Americans ≥20 years of age . Over thThe SNS is one of two branches of the nervous system that is involved in the regulation of numerous homeostatic mechanisms including cardiac function . The mai1-AR, β2-AR, β3-AR) with a fourth (β4-AR) remaining controversial  but are abundant in non-myocyte cells . On the other side, β1-AR is expressed at a low level in non-myocytes  activation, it is known that β2-AR and β3-AR can be coupled to inhibitory G protein according to studies which showed that their activity was pertussis toxin sensitive (Gαi) (αs subunit leads to activation of adenylyl cyclase (AC), which in turn catalyzes the local conversion of adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP). The rise in cAMP then triggers protein kinase A (PKA) activation by binding to its regulatory subunits and allowing the catalytic subunit to function. PKA then acts as a nodal point and further initiates the phosphorylation of effector molecules and subsequently a functional response. Effector molecules that are phosphorylated by PKA include phospholamban, L-type calcium channels, contractile proteins, β-AR itself, as well as many others  superfamily of receptors whose signaling plays a critical role in the regulation of the function and processes of the cardiovascular system. Presently, three subtypes of β-ARs have been characterized  . The acty others . Studiesy others . ACs canαs. Therefore, there must be a system in place to differentiate the signals when the different receptors are activated. Both β1-AR and β2-AR activate Gαs and downstream, AC and PKA. Specific stimulation of β1-AR can induce cardiac hypertrophy and/or promote cardiomyocyte apoptosis . GRKs are a family of seven serine/threonine protein kinases, which canonically recognize and phosphorylate agonist-activated GPCR’s in order to terminate signaling . This rerrestins . PKA is rrestins , 1999.The working paradigm regarding signal differentiation involves specific subcellular localizations that are isolated from each other. These distinct intracellular signaling compartments form “signalosomes” that mediate specific responses downstream of each receptor subtype . There aFigure 2). HF is characterized by hyperactivation of the SNS, leading to an increase in circulating CAs (NEpi and Epi)  from the adrenal medulla and augmented NEpi spillover from activated cardiac sympathetic nerve terminals into the circulation (1-AR density (around 50%) at the plasma membrane (downregulation) and by uncoupling of the membrane β1-ARs and β2-ARs from G proteins (desensitization) . When the role of β-ARs in diminished contractility in HF was first elucidated, the initial hypothesis was to increase inotropy through stimulation of cardiac β-ARs via agonists such as Epi, NEpi, and dobutamine as a clinical treatment for HF. However, the early enthusiasm diminished quickly, as patients either became hypertensive or arrhythmic after β-AR agonist therapy , hypertension, cardiomyopathies, valvular disorders, congenital heart diseases, rhythm abnormalities, and others. To counteract HF, it is crucial to understand the molecular mechanisms that interfere with the regulation of β-AR signaling (culation . SNS oveculation . In addiculation . Importaculation . At the ization)    . Hence, igure 2) . Studiesigure 2) . Conversigure 2) . Mice wiigure 2) . In addimyocytes . Studiesmyocytes , 2012b. myocytes . In addimyocytes . HF micemyocytes . Althougmyocytes .βγ protein-protein interaction   . Hence, function . InhibitF models . This isF models . StudiesF models . MoreoveF models .1-AR levels and improved cardiac inotropic reserve and sympathetic innervation in an animal model of ischemic HF  mice had increased cardiac contractility at a young age but after a few months developed marked myocyte hypertrophy and heart dysfunction (reduced EF). Moreover aged β1-AR Tg mice showed increased levels of interstitial collagen type-I/III and augmented levels/activity of matrix metalloproteinase-2 associated with severe fibrosis , and higher mortality (2-AR levels (300-fold overexpression) and taken together with the data of 2-AR overexpression is probably beneficial only at a low-moderate level . In particular, β-arrestins mediate β1-AR signaling to the EGFR and this mechanism is independent of G protein activation but involves GRK5 and GRK6  and effects on cardiac function and remodeling  and is less sensitive to desensitization compared to β1-AR and β2-AR   and dose of agonist used  . In particular, β3-AR overexpression in myocytes reduced myocardial interstitial fibrosis and increased angiogenesis in response to isoproterenol/angiotensin II infusions as well as a β3-AR agonist in mice submitted to transaortic constriction model (3-AR agonist) did not increase EF or affect LV volumes in HF patients   . Particumulation . These dow dose) . Intriguon model . NeverthF trial) . However3-AR dysfunction may be involved in patients that do not respond to β1-AR-blockers  receptor signaling that appears protective and beneficial  activity  and our group has studied their role in HF. Particularly, β-arrestin 1 knockout (KO) mice have shown improved cardiac function (enhanced EF and inotropic reserve) in a model of ischemic HF: the underlying mechanisms are, on one side, improved cardiac β-AR signaling and function due to cardiac β-arrestin 1 deletion, and on the other, decreased circulating levels of CAs and aldosterone due to adrenal β-arrestin 1 absence . Contrasactivity . On the 2-AR) via-anti apoptotic and anti-oxidative mechanisms  have been demonstrated to influence mitochondrial function and reactive oxygen species production in the heart. AKAP1 deletion led to mitochondrial alterations, enhanced mitophagy and increased infarct size as well as LV pathological remodeling in a model of post-ischemic HF . In addi1-ARs . Thus, Aαi, β-arrestins and GRK2, and counter-regulate each other . Hence, the main cellular mechanism for reduced cardiac β-AR responsiveness during aging is unknown. It is hypothesized that there is another mechanism other than GRKs that determines dysfunctional β-AR signaling during the aging process. Importantly, contrasting results have been published about cardiac Gαi levels content and activity. In one study, Gαi levels were measured in atrial tissues received from cardio-surgical patients and it was found that Gαi expression increased with age , as well (αi activity is unchanged in aged hearts (rat model) and probably do not contribute to the age-related reduction in cardiac β-AR dysfunction. Interestingly, another group found that Gαi content is unchanged while Gαi activity is increased in a Guinea-pig aging model  that are much more common in an older fragile heart . Interesαi activity appears to be altered in both conditions, as well. Although β-AR dysfunction in HF is primarily related to GRK2 upregulation, the mechanism involved in age-related β-AR altered levels/function is still unclear  (MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression during cardiac aging and age-related CVDs . miRNAs ibrosis) .Despite the increasing effort in basic research on the age-related cardiac dysfunction, clinical research is deeply underestimating the need for studies that include elderly patients. In fact, there is a huge disparity between research and market demand: patients ≥65 are under-represented in all phases of clinical trials, even though in HF, these patients are the primary drug users. In this regard, it would be important to invest  in development of treatments that will restore β-AR signaling in both HF and aging heart.The aged population is drastically increasing worldwide and it is mandatory to assure an adequate quality life to the elderly suffering from decreased cardiac function. In fact, age-related cardiac alterations and HF, deeply influence the autonomy and the ability to perform daily activities for elderly people. Importantly, HF is one of the most important comorbidities and causes of hospitalization and/or death for old people in western countries, dramatically affecting the cost of healthcare. Hence, there is a great need for treatments that ameliorate cardiac dysfunction in older people acting against both HF and cardiac physiological aging. Since β-AR signaling is dysfunctional in failing as well as aging heart, this pathway is an effective diagnostic and therapeutic target.All authors participated in writing the manuscript and/or revising it critically for important intellectual content.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Background: Circulating tumor cells (CTC), androgen receptor full-length (AR-FL), and androgen receptor splice variant 7 (AR-V7) are prognostic in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC). AR-V7 seems to predict resistance to androgen-receptor signaling inhibitors (ARSi). Methods: We assessed the association of CTC, AR-FL, and AR-V7 with prostate-specific antigen (PSA) response and overall survival (OS). We used a modified AdnaTest CTC-based AR-FL and AR-V7 mRNA assay. Chi-square test, Fisher Exact test, Kaplan–Meier method, log-rank test, Cox proportional hazards models were used as appropriate. Results: We enrolled 39 mCRPC pts, of those 24 started a first-line treatment for mCRPC (1L subgroup) and 15 had received at least two lines for mCRPC (>2L subgroup). CTC, AR-FL, and AR-V7 were enriched in >2L compared to 1L subgroup. Detection of these biomarkers was associated with a lower percentage of biochemical responses. Only 1/7 AR-V7+ pts had a PSA response and received cabazitaxel. Median OS was 4.7 months (95% CI 0.6–8.9) in AR-V7+ pts and not reached in AR-V7− pts. AR-V7 was the only variable with prognostic significance in the Cox model. Conclusion: AR-V7, CTC, and AR-FL are associated with advanced mCRPC and AR-V7+ predicts for shorter OS.  The treatment landscape of metastatic castration-resistant prostate cancer (mCRPC) has radically changed over recent years. Androgen-receptor signaling inhibitors (ARSi) and taxane-based chemotherapy have been established as valid treatment options for patients with mCRPC, by demonstrating a significant survival advantage in phase 3 trials . HoweverIn 2014, Antonarakis and colleagues investigated the role of AR-V7 in two small cohorts of patients treated with ARSi . The AdnScher and colleagues reproduced the results of Antonarakis using the Epic Sciences CTC platform that detected the nuclear-localized AR-V7 and analyzed the blood sample of 161 patients with mCRPC [The PROPHECY study investigated the role of AR-V7 in 118 poor-risk men treated with abiraterone or enzalutamide using both the modified-AdnaTest CTC AR-V7 mRNA assay and the Epic Sciences CTC nuclear-specific AR-V7 protein assay ,13,14,15Circulating androgen receptor (AR) copy number variations in plasma DNA have been also associated with worse outcome in mCRPC after treatment with ARSi ,17,18. IDespite these encouraging results, the predictive versus prognostic role of these variables has not been completely established yet and their significance as predictor of response is currently uncertain.This prospective study aimed to explore the prevalence and significance of CTC, AR-FL and AR-V7 in a cohort of patients with mCRPC. Ethics approval and consent to participate: informed written consent to blood collection and use for experimental purposes was obtained by all patients, following study-protocol approval by the local Ethical Committee (P.R.505REG2015).Patients with mCRPC referred to our Institution, who were starting a first-line treatment for mCRPC (1L subgroup) or who had been already treated with at least two lines for mCRPC (>2L subgroup), including at least one ARSi and one chemotherapy regimen, were invited to participate in this study. After informed consent, patients underwent a blood sample collection and were prospectively followed with PSA assessments every 4–6 weeks, until death or the limit date of 31 December 2018.To evaluate AR-FL and AR-V7 on CTC, 5 ml of blood was collected before starting a new line of therapy into dedicated test tube AdnaCollect  and processed within 2 hours as described in the study published by Antonarakis and colleagues . Brieflyp value < 0.05 at univariable analysis were included in the multivariable models. The performance of the models was measured using the concordance C-index [p values were two-tailed. The IBM software Statistical Package for Social Sciences (SPSS) version 25.0 for Windows  and the Software for Statistics and Data Science (STATA) version 11 were used for data analysis. Given the small sample size and the exploratory purpose of this study, adjustments for multiplicity were not performed.The statistical analysis was conducted using the chi-square test for categorical variables and Fisher Exact test when appropriate. Pearson’s correlation was used to test correlations among variables. PSA50 was the endpoint chosen for the analysis of biochemical response and was defined as a decline of at least 50% in PSA values from treatment start. OS was defined as the time elapsed from blood collection date and the date of death for any cause. OS curves were constructed according to the Kaplan–Meier method and compared using the log-rank test . The Cox C-index . All p vThirty-nine patients with mCRPC who met the inclusion criteria were enrolled in this study, of them 24 were included in the 1L subgroup and 15 in the >2L subgroup. After sample collection, 1L patients received abiraterone acetate, enzalutamide, or docetaxel, whereas treatments of >2L subgroup included abiraterone acetate, cabazitaxel, docetaxel, cyclophosphamide, enzalutamide, mitoxantrone, and vinorelbine. Drug dosages and schedules were those commonly used in clinical practice, according to physician choice and international guidelines on prostate cancer . The maip = 0.054). AR-FL mRNA was detected in 15/21 of CTC+ patients (71.4%); seven patients had less than 10 copies/mL and eight patients had ≥10 copies/mL; irrespective of the number of AR-FL copies, a higher percentage of AR-FL+ patients was found in the >2L subgroup than in the 1L subgroup . Overall, AR-V7 expression was detected in seven of 39 patients (17.9%); 2/24 patients (8.3%) were AR-V7 positive in the 1L subgroup and 5/15 patients (33.3%) were AR-V7 positive in the >2L subgroup (p = 0.08). None of our patients had detectable EGFR. AR-V7 correlated significantly with both AR-FL copies (r = 0.59 p < 0.001) and CTC detection (r = 0.43 p = 0.006).CTC were identified in 21 of the 39 blood samples (53.8%) . A highep = 0.03) (p = 0.008). Irrespective of treatment line, 5/11 (45%) patients who did not show any PSA response to therapies were AR-V7 positive. A higher percentage of biochemical responses were also observed in AR-FL negative compared to AR-FL positive patients ; however, three of seven patients (42.8%) with the highest number of AR-FL copies (≥10 copies/mL) reached the PSA50  A. Only ohe PSA50 B; two ofhe PSA50 D.Patients included in the 1L subgroup showed a higher number of PSA50 responses than patients who started a >2L treatment. PSA50 was reached in 19/24 (79.2%) patients included in the 1L cohort, compared to 4/15 (26.7%) patients included in the >2L subgroup A–C.Neither of the two AR-V7+ patients treated with ARSi reached the PSA50, whereas one AR-V7+ patient showed PSA50 response to third-line cabazitaxel. Of the four highly-pretreated patients who received palliative treatments , none showed a PSA response  B.p < 0.05), and we found that median PSA value, treatment line at study entry, number of metastatic sites, CTC status, AR-FL status, and AR-V7 status were all associated with OS (p = 0.01) (p < 0.000) (p = 0.002)  with a C-index of 0.92 (0.86–0.98)  A. The es< 0.000) B. Patien= 0.002) C. AR-V7 86–0.98) .C-indexes were 0.91 (0.84–0.96) for AR-V7/CTC, 0.90 (0.83–0.97) for AR-V7/AR-FL, and 0.92 (0.86–0.98) for AR-V7 alone.Consistently with literature reports ,21, we eIn the present study, we used a modified-AdnaTest CTC-based AR-FL and AR-V7 mRNA assay with custom primers , similarIn our exploratory cohort, we observed that CTC, AR-FL, and AR-V7 were all enriched in pretreated mCRPC patients compared to those starting a first-line regimen . This fiOverall, a lower percentage of biochemical responses was observed in the AR-V7+ patients than in AR-V7− . NeitherTo our knowledge, this is the first report that included a group of highly pretreated patients receiving palliative therapies. This population well represents a condition of intensive selective pressure from treatments (ARSi and chemotherapy). Of the four patients treated with cyclophosphamide, mitoxantrone, and vinorelbine, none showed a PSA response . This observation suggests that such treatments might not able to overcome the resistance induced by prior therapies and confirms the strong enrichment of AR-V7 and CTC in end-stage populations.AR-V7, AR-FL, and CTC were all identified as prognostic variables for OS in univariable analysis , but AR-In our exploratory prognostic nomograms, we did not find that the combination of AR-V7 with CTC or with AR-FL could better predict for patients’ prognosis compared to AR-V7 alone . This reWe also acknowledge that the significance of CTC, AR-FL, and AR-V7 in our prospective series might be at least partly amplified by the method for CTC detection and heterogeneity of the cohort. Notably, AR-V7 correlated with both AR-FL and CTC detection. There is a higher probability of detecting CTC, and in turn AR-FL/AR-V7, in a population with more advanced and incurable disease stage, because of the higher disease burden and higher number of CTC. This figure is confirmed by the highest PSA values that were observed in CTC+ AR-V7+ patients, followed by CTC+ AR-V7− and by CTC− AR-V7− patients . SimilarOur study confirms the prognostic role of AR-V7, whose detection might be relevant during the treatment choices for patients with mCRPC. AR-V7 seems to be the most promising biomarker to predict for response to ARSi, however a prospective validation study in chemotherapy-treated versus ARSi-treated patients is still needed to implement this test in clinical practice. In our small cohort, the combination of AR-V7 with CTC or with AR-FL did not outperform the prognostic model including only AR-V7. Further studies are strongly warranted to assess the role of these biomarkers in patients with mCRPC.


UCHL1; also known as PGP9.5) was one of the first discovered – yet remains enigmatic. Several reports have drawn connections between UCH-L1 and cancer – both as an oncogene and as a tumor suppressor. Recently, we have found new mechanistic insight into the activity of UCH-L1 may suggest how this one protein might do both . Womplexes . In maliHow then can an enzyme that mimics the activity of an anti-neoplastic drug drive the development of cancer? To answer this, we used a proximity-based proteomics approach to identify other proteins that associate with, or are substrates for, UCH-L1 [


Results: The panoramic X-ray showed a periapical lesion with the characteristics of a radicular cyst on tooth 21. The FlexiForce™ piezoresistive sensors allowed us to find that greater force (kg) was being applied to tooth 11 in comparison to tooth 21 during the embouchure mechanism. Conclusions: The sensors used in this research are acceptable for identifying the tooth where the greatest pressure is applied during the mouthpiece stabilization. In the case of executing an oral rehabilitation procedure for wind instrumentalists, a clinical examination can be complemented with the aid of bioengineering and the inherent development of sensor technology in order to better understand the embouchure mechanism. Likewise, the prosthetic rehabilitation should be taken into consideration in order to provide minimal changes to the musician’s performance.Introduction: A wind instrumentalist was diagnosed with a periapical lesion on tooth 21. The prosthetic rehabilitation options were considered with respect to the embouchure mechanism of the saxophonist. The underlying mechanism associated with the embouchure of the saxophone player was observed in this particular case in order to understand if asymmetrical forces were transmitted to the upper central incisors. Periapical lesions can be harmful to the oral health of musicians. The treatment options thus have to be taken into consideration with special focus on the need for oral rehabilitation on the anterior maxilla. Material and Methods: The patient underwent a radiographic examination with a panoramic X-ray. Subsequently, two piezoresistive sensors (FlexiForce™) were placed on the upper surface of the mouthpiece in order to quantify the pressure applied to the central incisors during the embouchure. In order to understand the values involved during this procedure, the saxophone player was required to play three different notes at different pitches: high, medium, and low. This procedure was repeated three times for each pitch in order to obtain a medium value for each note. Signal acquisition was obtained within software developed for this purpose, with the voltage output observed in LabView 2011 Wind instrumentalists display complex neuromuscular activity during their musical performances. As such, the embouchure and orofacial structures should be of major interest for dental practitioners. The orbicular muscles of single-reed instrument players can achieve bioelectric potential values of 40 µV, which may correspond to the double the normal values associated with the mastication process . In factSustained incisal pressure by the upper central incisors on the mouthpiece and the inherent habit of tolerating these forces is typical of wind instrumentalists. This force can be denominated as the maximal embouchure force (MEF), which according to the different registration tones (brass or treble) can induce different pressures on the orofacial tissues . To whatThe inclination of the mouthpiece inside the mouth can differ between clarinet and saxophone players. While the clarinet has an insertion of the mouthpiece more parallel to the inclination of the upper central incisors, the saxophone is placed in a more horizontal position. With respect to the grip of the embouchure, this can also be determined by the incisal edge of the upper central incisors, where any kind of irregularity or alteration on its inclined plane or in its smoothness will induce the adoption of a different position of the mouthpiece with respect to the upper teeth. With all these particularities, can we say there is a perfect embouchure? From a functional point of view the answer is yes, because the interface of the teeth and the mouthpiece will be adapted within the individual anatomical characteristics of each saxophonist.The masticatory neck and trunk muscle activity have an interrelation with the occlusion of the musician and his/her embouchure. Temporomandibular disorders  along with internal derangement of the temporomandibular joint  can be expected ,4,5. As The present study aimed to evaluate the pattern of the embouchure of a saxophone player who attended a dental appointment for a routine consultation, referring specifically that tooth 21 had an abnormal colour. This professional wind instrumentalist wanted to understand the possible treatment options and the following rehabilitation procedures in order eliminate the radicular cyst. In this particular case we must consider the enormous importance of tooth 21 with respect to the musical career of the patient, considering the professional, social, psychological, and economic impacts of treatment. A single missing anterior tooth is a challenge for most clinicians to restore in terms of aesthetics and function. Due to the multiple treatment modalities that are available to replace a single missing tooth, there are always different advantages and disadvantages for each case . Patient2) were placed on the upper surface of the mouthpiece in order to quantify the pressure applied to the central incisors during the embouchure. In order to understand the values involved during this procedure, it was requested that the saxophone player perform three different notes at different pitches: high, medium, and low. This procedure was repeated three times for each pitch in order to obtain a medium value for each note. The sensors were previously calibrated and integrated with the recommended circuit from Tekscan and connected to a four-channel Universal Analog Input Module 9219 mounted in a NI-USB 9162 Carrier . To achieve the recommended circuit, a TL074 STMicroelectonics operational amplifier was used. Sensor characterization was made through polynomial regression. In this way, four different weights  were applied to the sensors and the voltage output was observed with a LabVIEW 2011 Carrier . The FlexiForce Model A201-1 lb/sqi “TekScan” sensors were applied at specific locations on the mouthpiece as seen in This case report is of a female professional saxophone player. The collection of information on the patient’s general health was performed prior to the clinical examination. The musician underwent a radiographic examination which consisted of the acquisition of a panoramic X-ray . SubsequThe values were registered when recording the force applied to the musician’s teeth (11 and 21), while playing the saxophone. As seen in This paper intends to approach a theoretical and conceptual presentation where piezoelectric sensors can be a complementary tool in the assessment method for the diagnosis of embouchure force measurement. Currently, this method can be considered the most accurate exam for identifying the central incisor that applies the most pressure during musical performance . In thisThe capacity to play a wind instrument is dependent upon the balance of the CCMC and its healthy state. This single-reed instrument player presented an inflammation at the periapical region of the tooth, which eventually developed into granulation tissue from the wounding afforded by pulpal inflammation. This inflamed granulation tissue has been referred to historically as a periapical granuloma. Radiographically, the lesion is well-marked by a radiolucency that is present and associated with the apex of the tooth. Normally, a presumptive clinical-radiographic impression of a periapical cyst can be made in cases where the radiolucency has a diameter of greater than 20 mm . RadiculAccording to the prosthetic rehabilitation of the single tooth of this saxophone player, there are different treatment options. The systematic review conducted by Edelmayer et al. showed that in most studies, dental implants and fixed dental prosthesis (FDPs) are preferred, as compared to removable partial dentures (RPDs) as an alternative for missing single teeth . The autNevertheless, a removable prosthesis would in theory create difficulties in the stabilization of the mouthpiece during the musical performance. Hypothetically, this would happen if there was an equilibrium of the applied pressures induced by the central incisors on the mouthpiece, but what our study supports is that there is a higher demand placed on tooth 11 during the embouchure mechanism. Thus, a removable prosthesis on tooth 21 would not make a huge difference to the stabilization of the mouthpiece since the pressure applied on this tooth had a mean of 8 g compared to 72 g on tooth 11.As an alternative, a fixed partial denture from tooth 11 to 22 could be an option, especially considering the reduced time and cost for this procedure. However, in addition to the inherent cost of the treatment, the damage of the neighbouring teeth for crown preparation is also of importance. Moreover, this solution would place higher demand on the adaptation of the musician’s embouchure, since we would be changing not only the neuromuscular pattern of the embouchure (with a different distribution of pressure induced on the mouthpiece), but also the biomimetics of tooth 11.The implant procedure would avoid tooth preparation, which sometimes requires additional endodontic treatment. On the other hand, the placement of a dental implant on the post-extraction socket of tooth 21 would not be recommended due to the existing chronic periapical infection, as this may be considered as a risk factor (but not an absolute contraindication) for immediate implant placement. However, debridement of the alveolus should be performed and the implant surgery scheduled six months later. More than the cost, time required, and difficulty in performing treatment, a long-term solution for the specific case of our patient should be opted for . HaistreIn this particular case, due to the pathologic process involved in the surrounding bone tissue of tooth 21, the matter of immediate loading should not be considered, nor early loading. For this purpose, conventional loading is the most adequate loading protocol of the three options in implantology. However, when assessing prosthetic rehabilitation options in professional wind musicians, careful selection and specific treatment protocols are required so that the musician may continue playing.The conceptual approach explained in this article intends to highlight the possibility of using the piezoelectric sensors in the analysis of the clarinettist’s embouchure in order to understand and quantify the existing forces. In this case the wind instrument applies very low pressure on the tooth that will be replaced, and therefore the prosthondontic solution adopted will not change the embouchure of the musician since the greatest pressure is applied to tooth 11, which is not the target of the treatment. This theoretical analysis of the embouchure with the aid of piezoelectric sensors could be useful in the dentistry field. Nevertheless more studies should be made in order to provide greater knowledge on its practicability from a clinical point of view.MEF measurements are a relatively new modality that can be very useful in dental practice as a complementary tool in the diagnosis of wind instrumentalists’ embouchures. This system can be used as a part of complex treatment, as the case of the prosthodontic rehabilitation of this saxophone player. Therefore, this study has shown the effectiveness of this method in the elaboration of a treatment plan. The field of dentistry is undergoing considerable transformation with respect to the orofacial issues of wind instrumentalists, specifically, the musicians’ embouchure.Wind instrumentalists should regularly visit the dentist in order to evaluate their general oral health. Regarding the rehabilitation procedure, there should be a proposal to implement the most conservative treatment. If not, the recommended prosthetic rehabilitations options should embrace the physiological requirements of the wind instrumentalists’ embouchure while taking into account psychosocial aspects.The professional activity of these kind of patients have to be taken in consideration since there are economic matters related to the inhibition of musical performance during the prosthetic rehabilitation procedures. The piezoresistive FlexiForce™ sensors provide valid information that quantifies the pressure induced by the upper central incisors on the mouthpiece. In the future, this technique can be implemented in the screening of wind instrumentalists embouchure before and after oral rehabilitation.No patents may or will result from this work.