Miracle-dz/UniFAR-FTUs huggingface dataset:
How to find a codimension-one heterocliniccycle between two periodic orbits

Global bifurcations involving saddle periodic orbits have recently been recognized as being involved in various new types of organizing centers for complicated dynamics. The main emphasis has been on heteroclinic connections between saddle equilibria and saddle periodic orbits, called EtoP orbits for short, which can be found in vector fields in $\mathbb{R}^3$. Thanks to the development of dedicated numerical techniques, EtoP orbits have been found in a number of three-dimensional model vector fields arising in applications. We are concerned here with the case of heteroclinic connections between two saddle periodic orbits, called PtoP orbits for short. A homoclinic orbit from a periodic orbit to itself is an example of a PtoP connection, but is generically structurally stable in a phase space of any dimension. The issue that we address here is that, until now, no example of a concrete vector field with a non-structurally stable PtoP connection was known. We present an example of a PtoP heteroclinic cycle of codimension one between two different saddle periodic orbits in a four-dimensional vector field model of intracellular calcium dynamics. We first show that this model is a good candidate system for the existence of such a PtoP cycle and then demonstrate how a PtoP cycle can be detected and continued in system parameters using a numerical setup that is based on Lin's method.
NABGA: A Novel Algorithm to Align Biological Networks Based on Enhanced GCN and Network Aggregation

Biological network alignment is an important way to identify conserved modules between species as well as homologous proteins, while helping to discover evolutionary relationships and phylogenetic trees among different species. Like subgraph isomorphism, network alignment is an NP-hard problem and the network itself is complicated. Thus, an efficient computational network aligner is needed for network alignment. Therefore, this paper proposed a new PPI network alignment algorithm, NABGA. It constructs a multilayer GCN model to generate node embeddings. To reduce the impact of network noise to the model, NABGA uses data augmentation to simulate network noise and incorporates a training process to improve the robustness of the model. In addition, to reduce the time consumption of the algorithm, NABGA aggregates some specific nodes while keeping the network structure unchanged, which greatly improves the efficiency of the algorithm. The experimental results on real networks showed that the NABGA algorithm can produce results that outperform existing algorithms in both biological and topological indicators.
A Runtime-Reconfigurable Hardware Encoder for Spiking Neural Networks

In order for raw sensory data to be processed by spiking neural networks (SNNs) an intermediary spike encoder must translate that data into a spike-train. Since there is no one-size-fits-all encoding method suitable for every neuromorphic application, the necessary encoding scheme differs from one implementation to the next. A similar circumstance exists concerning the encoding interval, or frame, that a spike-train is produced for. Although research exists on individual encoding schemes with a rationale for excluding other methods for a particular application, no neuromorphic implementation has addressed a dedicated hardware encoder that is compatible with multiple encoding methods. In this study, we introduce an encoder module which supports three major encoding schemes. The encoding method, as well as the encoding frame duration, can be easily tweaked at runtime. Both FPGA and VLSI implementations have been created for this encoder that are highly scalable and fast, with the latter running with a clock frequency of up to 530 MHz in a 65-nm process. The small area and power footprint of this design makes it attractive for any hardware-based neuroprocessor without needing any external software, or hardware, based process for data encoding.
RFAM: RESET-Failure-Aware-Model for HfO2-based Memristor to Enhance the Reliability of Neuromorphic Design

Memristors are a suitable candidate to design synapse circuits and neuromorphic systems. Due to device and voltage variability, operating a memristive device with reliability is a big challenge. To enhance the reliability of memristive synapse, RESET failure needs to be considered. In this work, we are focused on RESET failure modeling with RESET voltage variation. Here, the RESET failure is defined as hard failure of the memristive synapse due to a high RESET voltage being applied. The proposed Verilog-A model is derived based on experimental data collected from 1T1R devices, which are fabricated on 65 nm CMOS process. To enhance the reliability of system-level simulation, this device model will provide better guidelines to the designer. In addition, power consumption for a successful RESET operation is 7.065 μW at 1.5 V, which can RESET the memristor resistance from 5 kΩ to 200 kΩ.
KPU-SQL: Kernel Processing Unit for High-Performance SQL Acceleration

Application-specific accelerator is a prominent way for analytic query processing. To achieve a substantial improvement over the state-of-the-art in performance while maintaining programmability, we propose a kernel processing unit (KPU) framework and apply it to SQL acceleration. Kernel customization and data transmission are two critical bottlenecks, we separately optimize them in the key core and shadow core with a self-designed data management system. A software stack named RACE with a performance model and function simulator is also introduced. The experiments demonstrate that KPU-SQL outperforms the CPU and GPU by 24.5x and 8.75x on average, respectively.
Sharp Weighted Estimates for Classical Operators [post-print]

We give a general method based on dyadic CalderonZygmund theory to prove sharp one and two-weight norm inequalities for some of the classical operators of harmonic analysis: the Hilbert and Riesz transforms, the Beurling-Ahlfors operator, the maximal singular integrals associated to these operators, the dyadic square function and the vector-valued maximal operator. In the one-weight case we prove the sharp dependence on the Ap constant by finding the best value for the exponent α(p) such that ‖Tf‖Lp(w) ≤ Cn,T [w] α(p) Ap ‖f‖Lp(w). For the Hilbert transform, the Riesz transforms and the BeurlingAhlfors operator the sharp value of α(p) was found by Petermichl and Volberg [47, 48, 49]; their proofs used approximations by the dyadic Haar shift operators, Bellman function techniques, and twoweight norm inequalities. Our proofs again depend on dyadic approximation, but avoid Bellman functions and two-weight norm inequalities. We instead use a recent result due to A. Lerner [34] to estimate the oscillation of dyadic operators. By applying this we get a straightforward proof of the sharp dependence on the Ap constant for any operator that can be approximated by Haar shift operators. In particular, we provide a unified approach for the Hilbert and Riesz transforms, the Beurling-Ahlfors operator (and their corresponding maximal singular integrals), dyadic paraproducts and Haar multipliers. Furthermore, we completely solve the open problem of sharp dependence for the dyadic square functions and vector-valued Hardy-Littlewood maximal function. In the two-weight case we use the very same techniques to prove sharp results in the scale of Ap bump conditions. For the singular integrals considered above, we show they map L(v) into L(u), 1 < p <∞, if the pair (u, v) satisfies sup Q ‖u‖A,Q‖v‖B,Q <∞, where Ā ∈ Bp′ and B ∈ Bp are Orlicz functions. This condition is sharp. Furthermore, this condition characterizes (in the scale of these Ap bump conditions) the corresponding two-weight norm inequality for the Hardy-Littlewood maximal operator M and its dual: i.e., M : L(v) −→ L(u) and M : Lp(u1−p) −→ Lp(v1−p). Muckenhoupt and Wheeden conjectured that these two inequalities for M are sufficient for the Hilbert transform to be bounded from L(v) into L(u). Thus, in the scale of Ap bump conditions, we prove their conjecture. We prove similar, sharp two-weight results for the dyadic square function and the vector-valued maximal operator. SHARP WEIGHTED ESTIMATES 3
PIM-trie: A Skew-resistant Trie for Processing-in-Memory

Memory latency and bandwidth are significant bottlenecks in designing in-memory indexes. Processing-in-memory (PIM), an emerging hardware design approach, alleviates this problem by embedding processors in memory modules, enabling low-latency memory access whose aggregated bandwidth scales linearly with the number of PIM modules. Despite recent work in balanced comparison-based indexes on PIM systems, building efficient tries for PIMs remains an open challenge due to tries' inherently unbalanced shape. This paper presents the PIM-trie, the first batch-parallel radix-based index for PIM systems that provides load balance and low communication under adversary-controlled workloads. We introduce trie matching-matching a query trie of a batch against the compressed data trie-as a key building block for PIM-friendly index operations. Our algorithm combines (i) hash-based comparisons for coarse-grained work distribution/elimination and (ii) bit-by-bit comparisons for fine-grained matching. Combined with other techniques (meta-block decomposition, selective recursive replication, differentiated verification), PIM-trie supports LongestCommonPrefix, Insert, and Delete in O(logP) communication rounds per batch and O(l/w) communication volume per string, where P is the number of PIM modules, l is the string length in bits, and w is the machine word size. Moreover, work and communication are load-balanced among modules whp, even under worst-case skew.
Constant RMR System-wide Failure Resilient Durable Locks with Dynamic Joining

We design two Recoverable Mutual Exclusion (RME) locks (a.k.a. durable locks) for the system-wide crash model. Our first algorithm requires only O(1) space per process, and achieves O(1) worst-case Remote Memory Reference (RMR) complexity in the Cache-Coherent (CC) model. Our second algorithm enhances the first algorithm to achieve (the same) O(1) space per process and O(1) worst-case RMR complexity in both the CC and Distributed Shared Memory (DSM) models. Furthermore, both algorithms allow dynamically created threads of arbitrary names to join the protocol and access the locks. To our knowledge, these are the only RME locks to achieve worst-case O(1) RMR complexity assuming nothing more than standard hardware support. In light of Chan and Woelfel's Ω(log n / log log n) worst-case RMR lower bound for RME in the individual crash model, our results show a separation between the system-wide crash and individual crash models in worst-case RMR complexity in both the CC and DSM models.
Towards a Tool to Support Students through Procedural Programming Guidance

Developing quality software is a complex activity because it combines reasoning, building, and testing skills. There exist different approaches to teaching these skills. Recent research by the Dutch Open University proposed a Procedural Guidance, which provides timely guidance through different views students can use to write code and tests. These views use a JML-influenced annotation language to attach specific information to each part of the code. The management and correct usage of these annotations has shown to be cumbersome. In this paper, we present a tool that aids students through highlighted annotations, view-specific information, warnings and errors, and the generation of test cases. To maximize its usability, the tool is distributed in the form of an add-on to a popular development environment.
An Efficient Scheduler for Task-Parallel Interactive Applications

Modern software is often interactive -- applications communicate frequently with the external world. For such applications, responsiveness -- how quickly they respond to requests -- is as important as throughput. Efficiently implementing these applications using traditional processes or static threads is difficult and error-prone. Task parallelism has the potential to significantly simplify the implementation of these applications -- it allows the programmer to express the high-level logical flow of the program and letting the scheduler handle the low level details of scheduling, synchronization, and asynchronous I/O operations. Researchers have begun to study how to best support such interactive applications where different components have different responsiveness on priority-oriented task-parallel platforms. We propose prompt I-Cilk, a practically efficient scheduler for priority-oriented task-parallel interactive applications. Our scheduler exhibits superior performance when compared to the state-of-the-art scheduler design, including on the Memcached object server, a large scale real-world interactive applications that we ported to run on a task-parallel platform. Our scheduler design defies the conventional folk wisdom on how to schedule task-parallel code -- we moved away from randomized work stealing, and we implemented "prompt'' scheduling with frequent checking of core-to-priority-level assignments. We show that such design choices make sense based on the workload characteristics of the parallel interactive applications we tested.
A Tight Characterization of Fast Failover Routing: Resiliency to Two Link Failures is Possible

To achieve fast recovery from link failures, most modern communication networks feature local fast failover mechanisms in the data plane. These failover mechanisms typically rely on pre-installed static rerouting rules which can depend only on local failure information. The locally limited failure information renders the problem of providing a high resilience algorithmically challenging. In this paper, we are interested in algorithms which tolerate a maximal number of k simultaneous link failures to guarantee packet delivery, as long as source and destination remain connected afterwards. Prior work showed that k=1 link failure can always be tolerated in general networks, but already the question of k=2 remained an unresolved problem. This paper closes this gap by presenting a tight characterization of fast failover routing: We show that 2-resiliency is possible with pre-installed static routing rules on general topologies, but that 3-resiliency is impossible already in relatively simple networks. Our 2-resilient routing scheme can be computed efficiently and relies on a careful kernelization and subdivision of the network topology into sparse subgraphs.
Comparative analysis of total protein, casein, lactose, and fat content in milk of cows suffering from subclinical and clinical mastitis caused by Streptococcus spp

Abstract Introduction The aim of the study was to analyse the total protein (TP), casein (CAS), lactose (LAC), and fat content of milk from cows with subclinical (SCM) and clinical mastitis (CM) caused by Streptococcus spp. Material and Methods A total of 60 milk samples from diseased cows and 30 milk samples from healthy cows were included in the study. Milk samples were taken from Holstein-Friesian cows from four dairy farms in Lublin Province. The bacteriological examination of the milk was performed and the somatic cells count in 1 mL of milk was determined using a SomaCount FC automatic cell counter. Determination of TP, CAS, LAC, FAT and FA levels in milk was carried out using a DairySpec FT automated Fourier transform infrared spectrometer. Results Total protein in milk from HE was significantly higher than in milk from cows with mastitis (4.04% vs 3.57% in milk from SCM cows and 3.7% in milk from CM cows, P = 0.001). The CAS level was 2.73% in milk from CM cows and 2.92% in milk from SCM cows vs 3.30% in milk from HE cows, P = 0.001. The changes in CAS and TP in milk resulted in a significant difference in the CAS/TP ratio (81.7% in milk from HE cows vs 73.8% in milk from CM cows). A decrease in levels was also recorded for LAC (4.8% in milk from HE cows vs 4.51% in milk from SCM cows and 4.01% in milk from CM cows, P = 0.001). The fat level was significantly higher in milk from healthy cows than in milk from cows with mastitis (4.0% vs 2.3% in milk from SCM cows and 1.64% in milk from CM cows, P = 0.001). Conclusion It should be emphasised that the decrease in the levels of TP, LAC and FAT was significant not only in milk from CM cows but also in milk from SCM cows. This is very unfavourable, because the reduction in the main milk components results in poor quality dairy products and impairs line processes.
Semisupervised support vector quantile regression

Unlabeled examples are easier and less expensive to be obtained than labeled examples. In this paper semisupervised approach is used to utilize such examples in an eﬀort to enhance the predictive performance of nonlinear quantile regression problems. We propose a semisupervised quantile regression method named semisupervised support vector quantile regression, which is based on support vector machine. A generalized approximate cross validation method is used to choose the hyper-parameters that aﬀect the performance of estimator. The experimental results conﬁrm the successful performance of the proposed S2SVQR.
How does organisational support improve job satisfaction? A moderated mediation analysis based on evidence from a global survey

We tested a moderated mediation model that examines the mediating role of personal accomplishment and the moderating role of work interest in the relationship between organisational support and job satisfaction among post-doctoral students/fellows. Our sample comprised 6 575 post-doctoral students/fellows from the 2020 Nature Survey. The result revealed that organisational support directly and positively related to job satisfaction, and indirectly related to job satisfaction via personal accomplishment. Work interest moderated the relationship between organisational support and personal accomplishment, and also moderated the mediating role of personal accomplishment in the relationship between organisational support and job satisfaction, associated with higher job satisfaction. The job demands-resources model may explain these findings in that job resources will generally produce positive psychological feelings, and ultimately raise job satisfaction. These findings deepen our understanding of the mechanisms for job satisfaction of early research career state employees considering organisation support and their personal factors.
Barcoding of episodic memories in the hippocampus of a food-caching bird

Episodic memory, or memory of experienced events, is a critical function of the hippocampus1–3. It is therefore important to understand how hippocampal activity represents specific events in an animal’s life. We addressed this question in chickadees – specialist food-caching birds that hide food at scattered locations and use memory to find their caches later in time4, 5. We performed high-density neural recordings in the hippocampus of chickadees as they cached and retrieved seeds in a laboratory arena. We found that each caching event was represented by a burst of firing in a unique set of hippocampal neurons. These ‘barcode-like’ patterns of activity were sparse (<10% of neurons active), uncorrelated even for immediately adjacent caches, and different even for separate caches at the same location. The barcode representing a specific caching event was transiently reactivated whenever a bird later interacted with the same cache – for example, to retrieve food. Barcodes co-occurred with conventional place cell activity6, 7, as well as location-independent responses to cached seeds. We propose that barcodes are signatures of episodic memories evoked during memory recall. These patterns assign a unique identifier to each event and may be a mechanism for rapid formation and storage of many non-interfering memories.
A Note on the Origin of the Twin Prime Conjecture

and whole numbers x , y , and z for which x + y = z . In 1640, as all mathematicians know, Fermat wrote this in a marginal note and claimed to have “an admirable proof” that, alas, did not fit within the space available. The result remained unproved for 350 years until Andrew Wiles, with assistance from Richard Taylor, showed that Fermat was indeed correct. On the other hand, there is the Goldbach conjecture, which asserts that every even number greater than 2 can be expressed as the sum of two primes. Goldbach shared this with Euler in 1742. Euler responded that he believed the result was true, but “I cannot prove it. ” Today – two and a half centuries later – no one else has done so. Alongside these two examples stands the twin prime conjecture (TPC). However, whereas the histories of Fermat’s Last Theorem and the Goldbach conjecture are well known, the origins of the twin prime conjecture are more uncertain. The conjecture itself is easy to state. We define twin primes as those that differ by 2 . Thus 3 and 5 are twins, as are 11 and 13 as well as 41 and 43. The twin prime conjecture says that there are infinitely many such pairs. As with the Goldbach conjecture, no one has yet been able to supply a proof. Some questions arise naturally: Where did the conjecture come from? Whose name should we attach to it? And when did it join the ranks of the famous problems of number theory? To answer these, we first look to the Comptes rendus of the French Academy of Sciences, dated 15 October, 1849, and to a paper titled “New Research on Prime Numbers” by Alphonse de Polignac. He was a French mathematician who lived from 1817 to 1890. There seems to be little information about him, except that he was an alumnus of the École Polytechnique and served as a sous-lieutenant in the French artillery. As the title suggests, de Polignac’s paper was about prime numbers, and on p. 400 he stated two “theorems. ” It should be noted that he was not using the word in its modern sense. Rather, de Polignac confirmed the truth of these results by checking a number of cases and thereby called them “theorems. ” Of course, we would call them, at best, “conjectures. ” The true nature of these statements is suggested by the fact that de Polignac introduced them under the heading “Induction and remarks” as seen below, in a facsimile of his original text.
Nitrogen source and Nod factor signaling map out the assemblies of Lotus japonicus root bacterial communities

Symbiosis with soil-dwelling bacteria that fix atmospheric nitrogen allows legume plants to grow in nitrogen-depleted soil. Symbiosis impacts the assembly of root microbiota, but it is not known how this process takes place and whether it is independent of nitrogen nutrition. We use plant and bacterial mutants to address the role of Nod factor signaling on Lotus japonicus root microbiota assembly. We found that Nod factors are produced by symbionts to activate Nod factor signaling in the host, and this modulates the assembly of a symbiotic root microbiota. Lotus plants grown in symbiosis-permissive or suppressive soils delineated three nitrogen-dependent nutritional states: starved, symbiotic, or inorganic. We found that root and rhizosphere microbiomes associated with these states differ in composition and connectivity, demonstrating that symbiosis and inorganic nitrogen impact the legume root microbiota differently. Finally, we demonstrated that selected bacterial genera delineating state-dependent microbiomes have a high level of accurate prediction.