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[Display omitted] • Rational block design (composition, sequence and length) has established a new diblock copolymer (BP 20) that realizes efficient cytosolic protein delivery both in vitro and in vivo. • When mixed with proteins, BP 20 forms stable nanoparticles and mediates efficient cytosolic delivery of a wide range of proteins including enzymes, toxic proteins and CRISPR/Cas9 ribonucleoproteins (RNP), to various cell lines. • BP 20 modified with folic acid (FA) enables tumor-targeted delivery of Saporin in vivo , which significantly suppresses the tumor growth. Polymer-mediated cytosolic protein delivery demonstrates a promising strategy for the development of protein therapeutics. Here, we propose a new designed diblock copolymer which realizes efficient cytosolic protein delivery both in vitro and in vivo. The polymer contains one protein-binding block composed of phenylboronic acid (PBA) and N-(3-dimethylaminopropyl) (DMAP) pendant units for protein binding and endosomal escape, respectively, followed by the response to ATP enriched in the cytosol which triggers the protein release. The other block is PEG designed to improve particle size control and circulation in vivo. By optimizing the block composition, sequence and length of the copolymer, the optimal one (BP 20) was identified with the binding block containing 20 units of both PBA and DMAP, randomly distributed along the chain. When mixed with proteins, the BP 20 forms stable nanoparticles and mediates efficient cytosolic delivery of a wide range of proteins including enzymes, toxic proteins and CRISPR/Cas9 ribonucleoproteins (RNP), to various cell lines. The PEG block, especially when further modified with folic acid (FA), enables tumor-targeted delivery of Saporin in vivo , which significantly suppresses the tumor growth. Our results shall inspire the design of novel polymeric vehicles with robust capability for cytosolic protein delivery, which holds great potential for both biological research and therapeutic applications. [ABSTRACT FROM AUTHOR]

In this note we answer positively a question of Chris Godsil and Karen Meagher on the existence of a 2-design whose block graph has a non-canonical maximum clique without a design structure. [ABSTRACT FROM AUTHOR]

A μ-way (v,k,t) trade T of volume m consists of μ pairwise disjoint collections Ti,...,Tμ, each of m blocks of size k such that for every t-subset of a v-set V, the number of blocks containing this t-subset is the same in each Ti for 1 ≤ i ≤ μ. If any t-subset of the v-set V occurs at most once in each Ti for 1 ≤ i ≤ μ, then T is called a μ-way (v, k, t) Steiner trade. In 2016, it was proved that there exists a 3-way (v, k, 2) Steiner trade of volume m when 12(k - 1) ≤ m for each k. Here we improve the lower bound to 8(k - 1) for even k, by using a recursive construction. [ABSTRACT FROM AUTHOR]

General Efficiency Balance (GEB) is an important property of designs. Variance balance and efficiency balance are special cases of GEB. Here, GEB block designs for comparing treatments belonging to two disjoint sets in the presence of systematic trend have been discussed. Methods of constructing Trend Resistant General Efficiency Balanced Bipartite Block Designs (TR-GEBBPB) designs have been presented. The block designs so obtained are trend resistant, GEB and are more efficient for estimating the contrasts pertaining to two treatments from two different sets.

Introduction: Functional Magnetic Resonance Imaging (fMRI) block-design experiments typically include active ON-blocks with presentation of cognitive tasks which are contrasted with OFF- blocks with no tasks presented. OFF-blocks in between ON-blocks can however, also be seen as a proxy for intermittent periods of resting, inducing temporary resting-states. We still do not know if brain activity during such intermittent periods reflects the same kind of resting-state activity as that obtained during a continuous period, as is typically the case in studies of the classic Default Mode Network (DMN). The purpose of the current study was therefore to investigate both similarities and differences in brain activity between intermittent and continuous resting conditions. Methods: There were 47 healthy participants in the 3T fMRI experiment. Data for the intermittent resting-state condition were acquired from resting-periods in between active task-processing periods in a standard ON-OFF block design, with three different cognitive tasks presented during ON-blocks. Data for the continuous resting-state condition were acquired during a 5 min resting period after the task-design had been presented. Results and discussion: The results showed that activity was overall similar in the two conditions, but with some differences. These differences were within the DMN network, and for the interaction of DMN with other brain networks. DMN maps showed weak overlap between conditions in the medial prefrontal cortex (MPFC), and in particular for the intermittent compared to the continuous restingstate condition. Moreover, DMN showed strong connectivity with the salience network (SN) in the intermittent resting-state condition, particularly in the anterior insula and the supramarginal gyrus. The observed differences may reflect a "carryover" effect from task-processing to the next resting-state period, not present in the continuous resting-state condition, causing interference from the ON-blocks. Further research is needed to fully understand the extent of differences between intermittent and continuous resting-state conditions. [ABSTRACT FROM AUTHOR]

Resolving sets were originally designed to locate vertices of a graph one at a time. For the purpose of locating multiple vertices of the graph simultaneously, {ℓ}-resolving sets were recently introduced. In this paper, we present new results regarding the {ℓ}-resolving sets of a graph. In addition to proving general results, we consider {2}-resolving sets in rook’s graphs and connect them to block designs. We also introduce the concept of ℓ-solid-resolving sets, which is a natural generalisation of solid-resolving sets. We prove some general bounds and characterisations for ℓ-solid-resolving sets and show how ℓ-solid- and {ℓ}-resolving sets are connected to each other. In the last part of the paper, we focus on the infinite graph family of flower snarks. We consider the ℓ-solid- and {ℓ}-metric dimensions of flower snarks. In two proofs regarding flower snarks, we use a new computer-aided reduction-like approach.

IntroductionFunctional Magnetic Resonance Imaging (fMRI) block-design experiments typically include active ON-blocks with presentation of cognitive tasks which are contrasted with OFF- blocks with no tasks presented. OFF-blocks in between ON-blocks can however, also be seen as a proxy for intermittent periods of resting, inducing temporary resting-states. We still do not know if brain activity during such intermittent periods reflects the same kind of resting-state activity as that obtained during a continuous period, as is typically the case in studies of the classic Default Mode Network (DMN). The purpose of the current study was therefore to investigate both similarities and differences in brain activity between intermittent and continuous resting conditions.MethodsThere were 47 healthy participants in the 3T fMRI experiment. Data for the intermittent resting-state condition were acquired from resting-periods in between active task-processing periods in a standard ON-OFF block design, with three different cognitive tasks presented during ON-blocks. Data for the continuous resting-state condition were acquired during a 5 min resting period after the task-design had been presented.Results and discussionThe results showed that activity was overall similar in the two conditions, but with some differences. These differences were within the DMN network, and for the interaction of DMN with other brain networks. DMN maps showed weak overlap between conditions in the medial prefrontal cortex (MPFC), and in particular for the intermittent compared to the continuous resting-state condition. Moreover, DMN showed strong connectivity with the salience network (SN) in the intermittent resting-state condition, particularly in the anterior insula and the supramarginal gyrus. The observed differences may reflect a “carry-over” effect from task-processing to the next resting-state period, not present in the continuous resting-state condition, causing interference from the ON-blocks. Further research is needed to fully understand the extent of differences between intermittent and continuous resting-state conditions.

In this paper we settle the question of whether a finite-dimensional vector space V over F p , with p an odd prime, and the family of all the k-sets of elements of V summing up to a given element x, form a 1- (v , k , λ 1) or a 2- (v , k , λ 2) block design, and, in either case, we find a closed form for λ i and characterize the automorphism group. The question is discussed also in the case where the elements of the k-sets are required to be all nonzero, as the two cases happen to be intrinsically inseparable. The "twin case" p = 2 , which has strict connections with coding theory, was completely discussed in a recent paper by G. Falcone and the present author. [ABSTRACT FROM AUTHOR]

Introduction. In the middle of the 20th century, technological progress made it possible to enlarge the building elements of buildings as much as possible, which led to the development of new industrial construction systems and increased production rates. However, to date, the issue has not been completely resolved and remains relevant. Modular construction is not sufficiently widely spread today, but many design experts predict its widespread introduction in the near future. The factor that decelerates the development of modular construction is the lack of theoretical foundations in the field of modular design, as well as significant differences from traditional design approach.Materials and methods. The purpose of this work is to develop the theoretical fundamentals of modular design based on the study of regulatory documents, Russian and foreign sources of research works, as well as the implemented projects. The task is to determine the fundamental features of modular elements of maximum readiness: principles of modular design, parameters of a modular element, advantages and disadvantages of a modular system, features of the design processes.Results. The theoretical basis of modular design includes basic concepts, principles and features; the conceptual design process is described using the case of development of an information model; parameters of modular elements of maximum readiness are presented, and the influence of modular items on the life cycle of a construction facility is analyzed.Conclusions. The presented system of principles of design based on modular elements of maximum readiness and parameters of modular elements allow us to systematize the established theoretical aspects of modularity, which make it possible to make modular buildings. The author formulates a new approach to design, which affects the entire life cycle and serves as the basis for new areas of engineering activities and scientific research.

The conventional approach to investigating functional connectivity in the block-designed study usually concatenates task blocks or employs residuals of task activation. While providing many insights into brain functions, the block design adds more manipulation in functional network analysis that may reduce the purity of the blood oxygenation level-dependent signal. Recent studies utilized one single long run for task trials of the same condition, the so-called continuous design, to investigate functional connectivity based on task functional magnetic resonance imaging. Continuous brain activities associated with the single-task condition can be directly utilized for task-related functional connectivity assessment, which has been examined for working memory, sensory, motor, and semantic task experiments in previous research. But it remains unclear how the block and continuous design influence the assessment of task-related functional connectivity networks. This study aimed to disentangle the separable effects of block/continuous design and working memory load on task-related functional connectivity networks, by using repeated-measures analysis of variance. Across 50 young healthy adults, behavioral results of accuracy and reaction time showed a significant main effect of design as well as interaction between design and load. Imaging results revealed that the cingulo-opercular, fronto-parietal, and default model networks were associated with not only task activation, but significant main effects of design and load as well as their interaction on intra- and inter-network functional connectivity and global network topology. Moreover, a significant behavior-brain association was identified for the continuous design. This work has extended the evidence that continuous design can be used to study task-related functional connectivity and subtle brain-behavioral relationships. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Neuropsychiatric assessment is essential part of child and adolescent psychiatry clinic practice, also provides important information about central nervous system dysfunctions. In studies conducted to date, it has been known that both the high frequency of psychiatric comorbidity in epileptic patients and that epilepsy comorbidity is quite common in neurodevelopmental disorders. In fact, considering the high comorbidity of epileptic abnormalities and psychiatric disorders, it has been very important to determine predictors for epileptic abnormalities in a clinical sample of child and adolescent psychiatry. In this retrospective study, we aim to determine possible predictive factors for epileptic abnormalities in a clinical sample of child and adolescent psychiatry according to Weschler Intelligence Scale for Children (WISC-R) results. METHODS: We identified patients who had two or more rotation errors in the block design subtest of WISC-R by retrospectively scanning the system records of 2609 cases who were applied WISC-R with different prediagnoses at Gazi University Child and Adolescent Psychiatry Outpatient Clinic between January 2013 and December 2020 (n=71). After the first step identification, we selected the ones who had a previous electroencephalography (EEG) recording available for our own re-review (n=60). RESULTS: We found 15% EEG abnormalities and ADHD is the most common diagnosis in both normal and abnormal EEG groups. Due to correlation analysis, there was a positive-mild correlation between presence of EEG abnormality and WISC-R performance (r=0.56) in intellectual disability (ID) group and a positive-strong correlation between presence of EEG abnormality and WISC-R performance-verbal scores (r=0.74) in ID group. CONCLUSION: This study has shown that many different abnormal EEG patterns can be found in patients who have rotation errors in the block design test of WISC-R, suggesting diagnoses of ID, and having notable performance-verbal subtests scores difference and rotation errors in the block design subtest of WISC-R should be predicitive factors for epileptic abnormalities. [ABSTRACT FROM AUTHOR]

The building envelope is a crucial element in the regulation of thermal energy in the indoor environment, from which comfortable living inevitably depends. Designing a low-dispersion envelope represents a fundamental strategy to minimize the energy demand and HVAC systems' consumption. To this end, the need to select suitable insulation has become increasingly important, and the search for new solutions is constantly evolving. This justifies the great interest in the study of energy-efficient and sustainable insulation materials that are able to provide the low thermal transmittance values of multilayer components. To date, 3D printing has experienced a growing popularity for the research of alternative building materials (e.g., concrete). Conversely, it still appears to be very uncommon for the research of purely energy-efficient solutions. The aim of this work is to compare the thermal performance of three 3D-printed PLA (polylactic acid) blocks, characterized by different internal geometries and air cavities: (i) a multi-row structure; (ii) a square structure; (iii) a honeycomb structure. The study was conducted theoretically, with two-dimensional heat transfer modeling, and experimentally, by means of a heat flow meter and infrared thermography. The results showed that the configurations of the 3D-printed blocks reduced the flow of heat exchange. In addition, as the complexity of the blocks' internal structure increased, a heat flow reduction could be observed. In particular, the honeycomb structure showed a better behavior than the other two blocks did, with an experimental transmittance value that was equal to 1.22 ± 0.04 W/m2K. This behavior, which was mainly due to an attenuation of convective and radiative internal heat exchanges, suggests that the 3D printing has great potential in this field. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a switching for 2-designs, which defines a type of trade. We illustrate this method by applying it to some symmetric (64, 28, 12) designs, showing that the switching introduced in this paper in some cases can be applied directly to orbit matrices. In that way we obtain six new symmetric (64, 28, 12) designs. Further, we show that this type of switching (of trades) can be applied to any symmetric design related to a Bush-type Hadamard matrix and construct symmetric designs with parameters (36, 15, 6) leading to new Bush-type Hadamard matrices of order 36, and symmetric (100, 45, 20) designs yielding Bush-type Hadamard matrices of order 100. [ABSTRACT FROM AUTHOR]

Let H be a connected subgraph of a graph G. An H-factor of G is a spanning subgraph of G whose components are isomorphic to H. Given a set H of mutually non-isomorphic graphs, a uniform H -factorization of G is a partition of the edges of G into H-factors for some H ∈ H . In this article, we give a complete solution to the existence problem for uniform (C k , P k + 1) -factorizations of K n − I in the case when k is even. [ABSTRACT FROM AUTHOR]

In this paper our focus is on regular signed graphs with exactly 3 (distinct) eigenvalues. We establish certain basic results; for example, we show that they are walk-regular. We also give some constructions and determine all the signed graphs with 3 eigenvalues, under the constraint that they are either signed line graphs or have vertex degree 3. We also report our result of computer search on those with at most 10 vertices.

Let H be a connected subgraph of a graph G. An H-factor of G is a spanning subgraph of G whose components are isomorphic to H. Given a set H of mutually non-isomorphic graphs, a uniform H-factorization of G is a partition of the edges of G into H-factors for some H∈H. In this article, we give a complete solution to the existence problem for uniform (Ck,Pk+1)-factorizations of Kn−I in the case when k is even.

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague.Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue.Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [F = 23.07, p < 0.009], with adjusted (R2 = 0.815) i.e., higher scores on Block design were associated with more fatigue.Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a broad time window for rehabilitation and information about fatigue. The clinical implications of the current findings are worth to be studied further.

Collaborative problem solving is more important than ever as the problems we try to solve become increasingly complex. Meanwhile, personal and professional communication has moved from face-to-face to computer-mediated environments, but there is little understanding on how the characteristics of these environments affect the quality of interaction and joint problem solving. To develop this understanding, methods are needed for measuring success of collaboration. For this purpose, we created a collaborative block design task intended to evaluate and quantify pair performance. In this task, participants need to share information to complete visuospatial puzzles. Two versions of the task are described: a physical version and one that can be completed in virtual reality. A preliminary study was conducted with the physical version (N = 18 pairs) and the results were used to develop the task for a second study in virtual reality (N = 31 pairs). Performance measures were developed for the task, and we found that pair performance was normally distributed and positively associated with visuospatial skills, but not with other participant-specific background factors. The task specifications are released for the research community to apply and adapt in the study of computer-mediated social interaction.

Rs9722 and rs1051169 have been reported as affecting the levels of S100B in the serum or the brain, and haplotypes containing these two SNPs have been associated with schizophrenia. The current study investigated the role of the S100B gene in an endophenotype of schizophrenia-spatial disability. 304 schizophrenia patients and 196 healthy controls were given a block design task and a mental rotation task. Results showed that the two aforementioned SNPs and related haplotypes were associated with the spatial disability of schizophrenia patients. Specifically, risk factors for the elevated S100B levels, including the A allele of rs9722, the G allele of rs1051169, and the AG haplotype, were associated with a poorer performance on both tests of spatial ability, especially the mental rotation task. These results implicate a role for S100B gene polymorphisms in the cognitive functions of schizophrenia patients and encourage further investigation into spatial disability as an endophenotype of schizophrenia.

Biosolids generated as waste from a Wastewater Treatment Plant (WTP) are a pollution problem by the provision of large volumes in landfills and the waste of their potential as an agricultural input. The research conducted trials to analyze the agricultural use of biosolids in a food company's WTP, their effects on the germination and development of the vegetal plant species Coriandrum sativum were assessed through trials that mixed different amounts of biosolids, land soil and commercial fertilizer, and took into account: planting site characteristics, biosolid and Coriandrum sativum. A random block design was made to compare treatments understudy and resulted in the combination of 50% biosolids with 50% land soil was the best test by germination, height, mass and length of the roots of the plant studied. In the evaluation of results, the behavior of dependent variables was analyzed: germination, height, mass and length with respect to the four test types with their respective repetitions using ANOVA and Fisher's significant minimum difference (LSD) to determine the effect the biosolid had on the plant and to know the optimal dose for its development. The germination rate (GR) was also determined in the trials, and 98.3% was found for the best treatment indicating that the substrate does not contain phytotoxic elements.

Facial synkinesis, a sequela of peripheral facial nerve palsy, is characterized by simultaneous involuntary facial movement during a voluntary desired one. Maladaptive cortical plasticity might be involved in the dysfunction of facial muscles. This cohort study investigated the cortical functional alterations in patients with unilateral facial synkinesis, using the task functional magnetic resonance imaging. Facial motor tasks, including blinking and smiling, were performed by 16 patients (aged 30.6 ± 4.5 years, 14 females/2 males) and 24 age- and sex-matched healthy controls (aged 29.1 ± 4.2 years, 19 females/5 males). Results demonstrated that activation in the cortico-facial motor representation area was lower during tasks in patients with facial synkinesis compared with healthy controls. Facial movements on either side performed by patients caused more intensive activation of the supplementary motor area on the contralateral side of the affected face, than those on the unaffected side. Our results revealed that there was cortical reorganization in the primary sensorimotor area and the supplementary motor area. This study was registered in Chinese Clinical Trial Registry (registration number: ChiCTR1800014630).

Background and Objective: Fatigue is common among stroke survivors; and has significant negative consequences. However, long-term follow-up on post-stroke fatigue and it's association with cognitive and physiological parameters remains vague. Methods: A prospective cohort study was carried out on 38 young stroke survivors (aged 18–65 at stroke onset) living in the community 10 years after first-ever stroke. Fatigue was assessed by Fatigue assessment scale (FAS). Global cognition and cognitive sub-domains were assessed repeatedly at 1 week, 7 months, and 10 years after their first-ever stroke. Univariate correlation analysis was used to investigate associations and multivariate regression was used to investigate predictors and association with fatigue. Results: At 10-years follow-up after stroke onset, more than half of the 38 participants suffered from fatigue [with median score 25 on FAS with 25–75% percentile (21–28)]. Most of them were independent in their everyday life [mRS median score 1 (0–2)]. In univariate correlation analyses, higher fatigue score was significantly correlated to higher independence in the daily activity, higher BMI, anxiety, higher scores on global cognition and better working memory at 10-years follow-up as well as better visuospatial functions after 7 months and 10-years. In a multiple regression analysis, only visuospatial function at 7-months follow-up was a significant predictor of fatigue 10 years after stroke onset [ F = 23.07, p < 0.009], with adjusted (R 2 = 0.815) i.e., higher scores on Block design were associated with more fatigue. Conclusion: Our results extended the time course of post-stroke fatigue up to 10 years after stroke onset. The participants with more fatigue performed better in cognitive assessments and daily activity, which indicated dissociation between fatigue and fatigability among stroke patients. Visuospatial function at the sub-acute phase predicted independently late post-stroke fatigue. This may offer a broad time window for rehabilitation and information about fatigue. The clinical implications of the current findings are worth to be studied further. [ABSTRACT FROM AUTHOR]

The MITSCHERLICH design entails a systematic arrangement of the treatments in a single row of plots. This arrangement allows forming "sliding" complete blocks across the whole design, for which moving averages can be computed. These means capture spatial trend and may be employed for correcting the observed data. The method, which is known as "slide method", does not have an underlying statistical model, meaning that the choice of best method for analysis remains an open question for these systematic designs. Furthermore, there is the question of the relative merit of a systematic design compared to randomized designs and that concerning the best method of analysis. These questions are of current interest because several long-term experiments laid out according to a systematic design are still in use today. In this contribution, we pursue these questions based on a newly proposed linear mixed model that can be thought of as underlying the slide method and which implies a linear geostatistical covariance structure. We also consider a two-dimensional extension of the MITSCHERLICH method, which VON BOGUSLAWSKI proposed under the term "response surface method". Our results show that a systematic arrangement is indeed optimal under the assumed model. This should not be taken to imply, however, that a systematic design is generally to be preferred to randomized designs, because it is not to be expected that the model proposed here provides the best fit among the large class of geostatistical models to any given dataset. The advantages of a randomized experimental design are emphasized in the conclusion. [ABSTRACT FROM AUTHOR]

This article introduces a blocked-design procedure for cognitive diagnosis computerized adaptive testing (CD-CAT), which allows examinees to review items and change their answers during test administration. Four blocking versions of the new procedure were proposed. In addition, the impact of several factors, namely, item quality, generating model, block size, and test length, on the classification rates was investigated. Three popular item selection indices in CD-CAT were used and their efficiency compared using the new procedure. An additional study was carried out to examine the potential benefit of item review. The results showed that the new procedure is promising in that allowing item review resulted only in a small loss in attribute classification accuracy under some conditions. Moreover, using a blocked-design CD-CAT is beneficial to the extent that it alleviates the negative impact of test anxiety on examinees' true performance. [ABSTRACT FROM AUTHOR]

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In this paper we consider a concept of strong regularity of signed graphs—a generalization of strong regularity of graphs. We establish certain structural and spectral properties of such signed graphs and determine or characterize those belonging to specified classes. Theoretical results are followed by examples and discussions. [ABSTRACT FROM AUTHOR]

We give explicit constructions for incomplete pairwise balanced designs IPBD((v; w), K), or, equivalently, edge-decompositions of a difference of two cliques K v \ K w into cliques whose sizes belong to the set K. Our constructions produce such designs whenever v and w satisfy the usual divisibility conditions, have ratio v / w bounded away from the smallest value in K minus one, say v / w > k - 1 + ϵ , for k = min K and ϵ > 0 , and are sufficiently large (depending on K and ϵ ). As a consequence, some new results are obtained on many related designs, including class-uniformly resolvable designs, incomplete mutually orthogonal latin squares, and group divisible designs. We also include several other applications that illustrate the power of using IPBDs as 'templates'. [ABSTRACT FROM AUTHOR]

We show that under certain conditions submatrices of row orbit matrices of strongly regular graphs span self-orthogonal codes. In order to demonstrate this method of construction, we construct self-orthogonal ternary linear codes from orbit matrices of the strongly regular graphs with parameters (70,27,12,9). Also we construct non self-orthogonal binary linear codes from these orbit matrices. Further, we obtain strongly regular graphs and block designs from codewords of the constructed codes. [ABSTRACT FROM AUTHOR]

Abstract In this paper we give constructions of self-orthogonal and self-dual codes, with respect to certain scalar products, with the help of orbit matrices of block designs and quotient matrices of symmetric (group) divisible designs (SGDDs) with the dual property. First we describe constructions from block designs and their extended orbit matrices, where the orbit matrices are induced by the action of an automorphism group of the design. Further, we give some further constructions of self-dual codes from symmetric block designs and their orbit matrices. Moreover, in a similar way as for symmetric designs, we give constructions of self-dual codes from SGDDs with the dual property and their quotient matrices. [ABSTRACT FROM AUTHOR]

The current pandemic has led schools and universities to turn to online meeting software solutions such as Zoom and Microsoft Teams. The teaching experience can be enhanced via the use of breakout rooms for small group interaction. Over the course of a class (or over several classes), the class will be allocated to breakout groups multiple times over several rounds. It is desirable to mix the groups as much as possible, the ideal being that no two students appear in the same group in more than one round. In this paper, we discuss how the problem of scheduling balanced allocations of students to sequential breakout rooms directly corresponds to a novel variation of a well-known problem in combinatorics (the social golfer problem), which we call the social golfer problem with adjacent group sizes. We explain how solutions to this problem can be obtained using constructions from combinatorial design theory and how they can be used to obtain good, balanced breakout room allocation schedules. We present our solutions for up to 50 students and introduce an online resource that educators can access to immediately generate suitable allocation schedules.

Although some patients have successful peripheral nerve regeneration, a poor recovery of hand function often occurs after peripheral nerve injury. It is believed that the capability of brain plasticity is crucial for the recovery of hand function. The supplementary motor area may play a key role in brain remodeling after peripheral nerve injury. In this study, we explored the activation mode of the supplementary motor area during a motor imagery task. We investigated the plasticity of the central nervous system after brachial plexus injury, using the motor imagery task. Results from functional magnetic resonance imaging showed that after brachial plexus injury, the motor imagery task for the affected limbs of the patients triggered no obvious activation of bilateral supplementary motor areas. This result indicates that it is difficult to excite the supplementary motor areas of brachial plexus injury patients during a motor imagery task, thereby impacting brain remodeling. Deactivation of the supplementary motor area is likely to be a serious problem for brachial plexus injury patients in terms of preparing, initiating and executing certain movements, which may be partly responsible for the unsatisfactory clinical recovery of hand function.

We study the asymptotically-achievable rate region of subspace codes for wireless network coding, where receivers have different link capacities due to the access ways or the faults of the intermediate links in the network. Firstly, an outer bound of the achievable rate region in a two-receiver network is derived from a combinatorial method. Subsequently, the achievability of the outer bound is proven by code construction, which is based on superposition coding. We show that the outer bound can be achieved asymptotically by using the code presented by Koetter and Kschischang, and the outer bound can be exactly attained in some points by using a q-analog Steiner structure. Finally, the asymptotically-achievable rate region is extended to the general case when the network has m receivers with different levels.

In this paper we consider the possibility that groups S n w r S 2 , 4 ≤ n ≤ 63 , act flag-transitively on block designs with n 2 points. We rule out n ∈ { 7 , 11 , 15 , 19 , 23 , 31 , 35 , 43 , 47 , 59 } and confirm the required action for other n in the given range through performing the construction of base blocks of the desired designs. Our construction makes use of flag-transitive incidence structures and weakly flag-transitive incidence structures. [ABSTRACT FROM AUTHOR]

Purpose The location of cortical areas and visual fatigue related to stereoscopic vision were explored by two types of fMRI designs, namely block stimulation and event-related stimulation. The stimulations consist of 2D/3D images and different depths of the stereoscopic 3D images. Method 20 normal subjects were randomly divided into the block group and the event-related group. Blood oxygenation level-dependent functional magnetic resonance imaging (Bold-fMRI) was performed in two groups. Functional data was preprocessed and statistically analyzed by SPM8. The result was reported by REST. Result In the block stimulation group, compared to 2D image stimulation, 3D image stimulation results in more activated brain areas, including frontal lobes, occipital lobes and limbic lobes, especially in the frontal eye field (Brodmann Area 8, BA8) and middle occipital gyrus (BA18/19). In the event-related group, compared to 2D images, viewing 3D images causes significant activations in temporal lobe, mainly represented in BA19/13/31/37. Additionally, 3D image stimulation with the focus set at front depth can lead to the activation of more brain areas compared to the back depth, including inferior parietal lobule and posterior central gyrus. Conclusion The formation of the stereoscopic vision requires the collaboration of more brain areas, so that viewing stereoscopic videos for a long period may result in visual fatigue; meanwhile, the front depth of field can contribute to more activated brain areas than the back depth of field. As a parameter of stereoscopic images, it is valid to state that the depth of field may affect visual fatigue. [ABSTRACT FROM AUTHOR]

Introduction: Proper nutrition is critical for maximizing brain function and enhancing learning. There is accumulating evidence that early malnutrition, marked by stunting, is associated with long-term deficits in cognitive and academic performance, even when social and psychological differences are controlled. All over the world, children living without permanent parental care are at a heightened risk for under-nutrition, putting their health and development in great jeopardy. Aim: To assess the nutritional and cognitive status in institutionalized orphans which might help to formulate effective interventions for improving the nutritional status of vulnerable children in future. Materials and Methods: This cross-sectional, study included 70 children (35 orphans and 35 non-orphans). Their anthropometric measurements (height, weight, and BMI) were measured and cognition was assessed using subsets of Wechsler Intelligence Scale for Children-Revised (WISC-R): Block design and Digit span. The data obtained was subjected to descriptive statistical analysis. Results: 18.57% (13) of children had stunting, 15.71% (11) had wasting, 22.86% (16) were underweight, and 17.14% (12) showed thinness. Mean±SD of Block design in non-orphans was significantly higher compared to orphans (p-value 0·05). Mean±SD of Digit span in non-orphans was significantly higher compared to orphans (p-value 0·000). For Block design, there was moderate positive correlation with nutritional status based on Z-scores (p-value

A generalization of Ding’s construction is proposed that employs as a defining set the collection of the sth powers ( s ≥ 2 ) of all nonzero elements in G F ( p m ) , where p ≥ 2 is prime. Some of the resulting codes are optimal or near-optimal and include projective codes over G F ( 4 ) that give rise to optimal or near optimal quantum codes. In addition, the codes yield interesting combinatorial structures, such as strongly regular graphs and block designs.

In this paper we characterize distance-regular graphs with diameter three having exactly three distinct distance eigenvalues, and also bipartite distance-regular graphs with diameter four having three distinct distance eigenvalues. We derive some properties and give particular examples of such graphs. We also present an infinite family of bipartite semiregular graphs with diameter four having exactly four distinct distance eigenvalues. With these results, we address some problems posed in Atik and Panigrahi (2015) [3] . [ABSTRACT FROM AUTHOR]

In this paper we classify 2 -designs and 3 -designs with 28 or 36 points admitting a transitive action of the unitary group U ( 3 , 3 ) on points and blocks. We also construct 2 -designs and 3 -designs with 56 or 63 points and strongly regular graphs on 36, 63 or 126 vertices having U ( 3 , 3 ) as a transitive automorphism group. Further, we show that this completes the classification of 3 -designs admitting a transitive action of the group U ( 3 , 3 ) , in terms of parameters. A number of the 3 -designs and 2 -designs obtained in this paper have not been known before up to our best knowledge. [ABSTRACT FROM AUTHOR]