cssi/SciSciGPT-SciSciNet huggingface dataset:
The Future of Fragile X Syndrome: CDC Stakeholder Meeting Summary

* Abbreviations: ASD — : autism spectrum disorder CDC — : Centers for Disease Control and Prevention FMR1 — : fragile x mental retardation 1 FMRP — : fragile X mental retardation protein FXD — : fragile X–associated disorder FXS — : fragile X syndrome ID — : intellectual disability Fragile X syndrome (FXS) is the most common known inherited cause of intellectual disability (ID). Males and females with FXS exhibit a wide range of intellectual ability and may experience various degrees of emotional, behavioral, sensory, learning, and social difficulties. In 1991, the gene responsible for FXS was identified on the X chromosome at q27.3 and named fragile x mental retardation 1 ( FMR1 ) gene.1 FXS and fragile X–associated disorders (FXD) are caused by a trinucleotide repeat (CGG) expansion mutation in the promoter region (exon 1) of FMR1 . Affected individuals with the full FXS mutation have >200 repeats. When the full mutation is present, FMR1 methylation occurs during gestation, which causes silencing of gene transcription.2 This in turn leads to a reduction or absence of fragile X mental retardation protein (FMRP), which is needed for brain development and function. Most males with FXS have ID. A small number of males have less impaired function due to methylation patterns or mosaicism. In females, FMRP levels depend on the X activation ratio, or the percent of cells expressing the normal allele on the active X chromosome,3 resulting in a range of normal intellectual ability to moderate ID. Over the past 2 decades, scientists have made significant advancements in identifying and describing genetic, molecular, and cellular underpinnings of FXS, allowing for a more precise diagnosis of this condition. The present challenge is to move from accurate diagnosis to public health action for FXS, requiring better understanding of the natural history of FXS, … Address correspondence to Julie Bolen, PhD, MPH, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, 4770 Buford Hwy (E-88), Atlanta, GA 30341. E-mail: jcr2{at}cdc.gov
Sudden Cardiac Death in US Young Adults, 1989-1996

0007 Anecdotal evidence and case reports indicate that sudden cardiac death (SCD) occurs in adolescents and young adults. To investigate the epidemiologic pattern and secular trend of SCD among ages 15-34 years, we analyzed US Multiple Causes of Death data from 1989 to 1996. SCD is defined as death due to cardiac disease (ICD-9 codes: 390-398, 402 and 404-429)that occurred out of hospital or in emergency room. This definition has been used in prior studies with reasonable accuracy. Mortality rates were calculated using mid-year population estimates as the denominators, and standardized to 1970. In 1996, 3,000 sudden cardiac deaths occurred for this specific age group, which reflects a 10% increase from 1989 (n=2,719). The leading underlying causes of SCD were ischemic heart disease (ICD codes 410-414, and 429.2), and arrhythmias or cardiomyopathies (ICD codes 425-427), each accounting for 35% of all SCDs. SCD mortality rates were twice as high in men as in women, and increased with age. From 1989 to 1996, age-standardized SCD mortality rates increased in both men (+10%) and women (+31%) (Figure). Although SCD is relatively rare in US adolescents and young adults, the increased trend of SCD mortality warrants further investigation. This is the first national surveillance report on SCD in young adults.
Cardiac Progenitor Cell Recruitment Drives Fetal Cardiac Regeneration by Enhanced Angiogenesis

Background In contrast to adults, the fetal response to myocardial infarction (MI) is regenerative, requiring the recruitment of cardiac progenitor cells to replace infarcted myocardium. Macrophage contribution to tissue repair depends on their phenotype: M1 are proinflammatory and initiate angiogenesis; M2a are profibrotic and contribute to blood vessels maturation; and M2c are proremodeling and proangiogenesis. The goal of the present study was to expand on this work by examining cardiac progenitor cells recruitment, and the role of macrophages in promoting angiogenesis and cardiac regeneration in the fetal heart after MI. Methods Fetal and adult sheep underwent MI and were sacrificed 3 or 30 days after MI. Some fetal hearts received stromal cell-derived factor-1α-inhibitor treatment. The microvasculature was evaluated by micro–computed tomography, gene expression was evaluated by real-time polymerase chain reaction, and vessels counts were evaluated by immunohistochemistry. Results Micro–computed tomography analysis showed restoration of microvasculature in fetal hearts after MI. Vascular endothelial growth factor-α increased, and the expression of tissue markers associated with the M1, M2a, and M2c macrophage phenotypes were elevated at day 3 after MI, but returned to baseline by 30 days after MI. In contrast, adult hearts after MI exhibited low vascular endothelial growth factor-α and persistent upregulation of all macrophage markers, consistent with prolonged inflammation, fibrosis, and remodeling. Inhibition of stromal cell-derived factor-1α in fetal infarcts prevented angiogenesis, decreased vascular endothelial growth factor-α, and was associated with a sustained increase in M1, M2a, and M2c markers after MI. Conclusions Changes in angiogenesis and macrophage phenotype-related gene expression after MI are important for the fetal regenerative response to MI and are mediated at least in part by cardiac progenitor cells recruitment.
A bipyridine-ligated zinc(II) complex with bridging flavonolate ligation: synthesis, characterization, and visible-light-induced CO release reactivity.

Metal–flavonolate compounds are of significant current inter­est as synthetic models for quercetinase enzymes and as bioactive compounds of importance to human health. Zinc–3-hy­droxy­flavonolate compounds, including those of quercetin, kampferol, and morin, generally exhibit bidentate coordination to a single ZnII center. The bi­pyridine-ligated zinc–flavonolate compound reported herein, namely bis­(μ-4-oxo-2-phenyl-4H-chromen-3-olato)-κ3O3:O3,O4;κ3O3,O4:O3-bis­[(2,2′-bi­pyridine-κ2N,N′)zinc(II)] bis­(perchlorate), {[Zn2(C15H9O3)2(C10H8N2)2](ClO4)2}n, (1), provides an unusual example of bridging 3-hy­droxy­flavonolate ligation in a dinuclear metal complex. The symmetry-related ZnII centers of (1) exhibit a distorted octa­hedral geometry, with weak coordination of a perchlorate anion trans to the bridging deprotonated O atom of the flavonolate ligand. Variable-concentration conductivity measurements provide evidence that, when (1) is dissolved in CH3CN, the complex dissociates into monomers. 1H NMR resonances for (1) dissolved in d6-DMSO were assigned via HMQC to the H atoms of the flavonolate and bi­pyridine ligands. In CH3CN, (1) undergoes qu­anti­tative visible-light-induced CO release with a quantum yield [0.004 (1)] similar to that exhibited by other mononuclear zinc–3-hy­droxy­flavonolate complexes. Mass spectroscopic identification of the [(bpy)2Zn(O-benzoyl­salicylate)]+ ion provides evidence of CO release from the flavonol and of ligand exchange at the ZnII center.
A Deep Learning Model for Predicting Tumor Suppressor Genes and Oncogenes from PDB Structure

While cancer is a heterogeneous complex of distinct diseases, the common underlying mechanism for uncontrolled tumor growth is due to mutations in proto-oncogenes and the loss of the regulatory function of tumor suppression genes. In this paper we propose a novel deep learning model for predicting tumor suppression genes (TSGs) and proto-oncogenes (OGs) from their Protein Data Bank (PDB) three dimensional structures. Specifically, we develop a convolutional neural network (CNN) to classify the feature map sets extracted from the tertiary protein structures. Each feature map set represents particular biochemical properties associated with the atomic coordinates appearing on the outer surface of protein9s three dimensional structure. The experimental results on the collected dataset for classifying TSGs and OGs demonstrate promising performance with 82.57% accuracy and 0.89 area under the ROC curve. The initial success of the proposed model warrants further study to develop a comprehensive model to identify the cancer driver genes or events using TSG and OG as the basis to track the causal chain.
PHILOSOPHY OF ARCHAEOLOGY

The philosophy of archaeology addresses philosophical issues as they arise in the discipline of archaeology. This article takes up several epistemological and ethical concerns. The former include problems concerning definition and classification, evidence and confirmation, and the nature of explanation. Ethical issues in this article focus on the principles that govern the acquisition and preservation of archaeological materials and the dissemination of archaeological knowledge.
Mental Models of Cause and Inheritance for Type 2 Diabetes Among Unaffected Individuals Who Have a Positive Family History

Using the familial risk perception (FRP) model as a framework, we elicited causal and inheritance explanations for type 2 diabetes (T2D) from people who do not have T2D but have a family history for it. We identified four composite mental models for cause of T2D: (a) purely genetic; (b) purely behavioral/environmental; (c) direct multifactorial, in which risk factors interact and over time directly lead to T2D; and (d) indirect multifactorial, in which risk factors interact and over time cause a precursor health condition (such as obesity or metabolic syndrome) that leads to T2D. Interestingly, participants described specific risk factors such as genetics, food habits, lifestyle, weight, and culture as "running in the family." Our findings provide insight into lay beliefs about T2D that can be used by clinicians to anticipate or make sense of responses to questions they pose to patients about mental models for T2D.
Rat Renal Papillary Structure in Oxalate-Induced Microlithiasis, A Scanning Electron Microscope Study

Most commonly, renal stones are found in the renal calyces or pelvis and several of the hypotheses concerning calculogenesis implicate the papilla as having a central role. Attention was first focused on this region of the kidney by Randall1,2,3, who described minute calculi and calcium plaques on and within renal papilla. Vermeulen et al.4,5 extended these observations in a series of experiments which suggested that the papillary tip was critical in the formation of various types of stones. However, few current studies are available which explore changes in the renal papilla during experimental calculogenesis. To extend further the knowledge of papillary involvement in lithogenesis we examined structural alterations of the papillary surface during calcium oxalate crystalluria.
Assessing the credibility of vehicle data reported by anonymous sources

Intelligent Transportation Systems (ITS) perform analyses and make recommendations related to traffic based on data received. In general, the more data available, the more accurate and or timely the results. There exists a plethora of untapped data sources in the form of smart devices, such as smartphones, and vehicles with driver-assist technology. Accepting data haphazardly, however from any available source may put the ITS system integrity at risk resulting in potential increases false positives or negatives or delayed detection of true positive traffic events. This paper looks at using Support Vector Machine (SVM) algorithms to classify reported vehicle behavior as good or bad so a decision as to whether or not to consider reports from those sources can be made. Using simulated data, three algorithms were applied and the results analyzed.
Determining species-specific nightly bat activity in sites with varying urban intensity

Time of peak bat activity during the night differs among bat species due to temperature, prey availability, habitat availability, and/or interactions between species. Habitat availability is altered in urban areas, which may affect insect prey availability and interspecies interactions. Our objectives were to use mobile acoustic monitoring to determine when bat species were active in a single night in urban and nonurban sites and if nightly bat activity patterns differed in urban versus nonurban sites. Bat echolocation call sequences were recorded using Anabat acoustic detectors while driving transects through the night at five sites (three “urban” and two “nonurban”) located in the Piedmont region of north-central North Carolina from May through August 2016. Transects were driven three times per night starting 45 min, 180 min, and 300 min after sunset. Recorded echolocation call sequences were analyzed manually using AnalookW and automatically using Bat Call Identification and Echoclass software. Total bat activity was not different between urban and nonurban sites. However, total bat activity was lower later in the night in urban sites, but stayed the same in nonurban sites. Species specifically, there were more Eptesicus fuscus, Lasionycteris noctivagans, and Tadarida brasiliensis call sequences and fewer Lasiurus borealis, Nycticeius humeralis, and Perimyotis subflavus call sequences in urban sites than nonurban sites. There were also fewer E. fuscus, L. noctivagans, and N. humeralis call sequences later in the night in both urban and nonurban sites. Only Lasiurus borealis activity in urban sites later in the night reduced and L. borealis activity in nonurban sites remained at the same. These results suggest that bats in urban areas partition time differently, which is important to consider for urban conservation efforts and planning.
Infrared laser ablation and capture of enzymes with conserved activity.

Abstract Infrared (IR) laser ablation at 3 μm wavelength was used to extract enzymes from tissue and quantitatively determine their activity. Experiments were conducted with trypsin, which was ablated, captured and then used to digest bovine serum albumin (BSA). BSA digests were evaluated using matrix-assisted laser desorption ionization (MALDI) mass spectrometry (MS) and sequence coverage of 59% was achieved. Quantification was performed using trypsin and catalase standards and rat brain tissue by fluorescence spectroscopy. Both enzymes were reproducibly transferred with an efficiency of 75 ± 8% at laser fluences between 10 and 30 kJ/m 2 . Trypsin retained 37 ± 2% of its activity and catalase retained 50 ± 7%. The activity of catalase from tissue was tested using three consecutive 50 μm thick rat brain sections. Two 4 mm 2 regions were ablated and captured from the cortex and cerebellum regions. The absolute catalase concentration in the two regions was consistent with previously published data, demonstrating transfer of intact enzymes from tissue.
Moratorium est finie

One existential night Vorgis IV and Bartolom? V sat dreaming poles apart, in terra firma of varying climate and automation. Now V was born paraplegic, as was B; and both were guilty of parricide in adolescence. Neither knew the other by sight but had to this date corresponded prolifically?oh, such electric love letters, punctuated by all manner of dash and diminuendo. This infatuation was all the more chaotic since it was stagebound, blessed with neither touch nor token, yet producing a pas des deux nonetheless. Their favorite charades: Deux ex machina. Having conceived a bestiary, they also concocted a real weirdo: Man, a composite-facsimile drawn from oral legends. Their love letters then were hypo thalamusical?partial to artifacts corroborating the historicity of Romeo and Juliet, even extending to a definitive chronicling of Adam and Eve. Such thesis-baiting and its resultant rhetoric ignited V & B, who were of the eidetic syndrome. And quite lovingly,?always by long distance?they would litigate cases of biblical/ historical amour. Ergo: wasn't Anne Bolynn a mite too incontinent for the brutish Henry VIII? Had Samson been ahead of his time and refused to be clipped, De lilah wouldn't have that maxi-rep today. Like that. V's and B's integrated memor ies were inexhaustible; they could ad lib eternity. Regardless of how tuned-in they were, V & B were doomed to an inertial worship. Like mummies, they were encrypted, unrequited. Vibration was their umbilical; and in this they were patho logical linguists. Their ardor hinged on voltage, frequency. Should they ever come together, their copulation would have to be nothing short of cannibalism. Orgasm could be traumatic to both. The realization that they were physically anathematic dimmed this otherwise radiant twosome. To compensate, they resorted to telepa thy, malevolently and multilingually. Therefore . . .
Widespread antisense transcription of Populus genome under drought.

Antisense transcription is widespread in many genomes and plays important regulatory roles in gene expression. The objective of our study was to investigate the extent and functional relevance of antisense transcription in forest trees. We employed Populus, a model tree species, to probe the antisense transcriptional response of tree genome under drought, through stranded RNA-seq analysis. We detected nearly 48% of annotated Populus gene loci with antisense transcripts and 44% of them with co-transcription from both DNA strands. Global distribution of reads pattern across annotated gene regions uncovered that antisense transcription was enriched in untranslated regions while sense reads were predominantly mapped in coding exons. We further detected 1185 drought-responsive sense and antisense gene loci and identified a strong positive correlation between the expression of antisense and sense transcripts. Additionally, we assessed the antisense expression in introns and found a strong correlation between intronic expression and exonic expression, confirming antisense transcription of introns contributes to transcriptional activity of Populus genome under drought. Finally, we functionally characterized drought-responsive sense–antisense transcript pairs through gene ontology analysis and discovered that functional groups including transcription factors and histones were concordantly regulated at both sense and antisense transcriptional level. Overall, our study demonstrated the extensive occurrence of antisense transcripts of Populus genes under drought and provided insights into genome structure, regulation pattern and functional significance of drought-responsive antisense genes in forest trees. Datasets generated in this study serve as a foundation for future genetic analysis to improve our understanding of gene regulation by antisense transcription.
Vibro-impact responses of a tube with tube--baffle interaction. [LMFBR]

The relatively small, inherent tube-to-baffle hole clearances associated with manufacturing tolerances in heat exchangers affect the vibrational characteristics and the response of the tube. Numerical studies were made to predict the vibro-impact response of a tube with tube-baffle interaction. The finite element method has been employed with a non-linear elastic contact spring-dashpot to model the effect of the relative approach between the tube and the baffle plate. The coupled equations of motion are directly integrated with a proportional system damping represented by a linear combination of mass and stiffness. Lumped mass approach with explicit time integration scheme was found to be a suitable choice for tube-baffle impacting analysis. Fourier analyses indicate that the higher mode contributions to the tube response are significant for strong tube-baffle impacting. The contact damping forces are negligible compared with the contact spring forces. The numerical analysis results are in reasonably good agreement with those of the experiments.
Hidden and Nonlocal Symmetries of Nonlinear Differential Equations

New results on hidden and nonlocal symmetries of nonlinear ordinary differential equations (NLODEs) are presented. Two types of hidden symmetries have been identified. A type I (II) hidden symmetry of an ODE occurs if a symmetry is lost (gained) when the order of the ODE is reduced. Both type I and type II hidden symmetries are found in the reduction of a third-order NLODE invariant under a three-parameter nonsolvable Lie group. Nonlocal group generators are determined of the exponential form and a new linear form. The ODEs can be reduced by the nonlocal group generators until first-order ODEs are obtained where the procedure fails because canonical coordinates cannot be calculated in that case. ODEs cannot be reduced by the linear nonlocal group generators.
Continuous Classification of Locomotor Transitions Performed Under Altered Cutting Style, Complexity and Anticipation

Intent recognition strategies for lower-limb assistive technologies (e.g., prostheses and exoskeletons) are typically limited to transitions from one terrain to another (e.g., level ground to stairs) occurring under anticipated cognitive states and in a straight path. However, such systems might be unable to robustly handle unanticipated transitions and those that do not occur in a straight line, posing high fall and injury risks for individuals suffering from cognitive and/or physical impairments. Understanding how classification of human locomotion is influenced by changes of direction and user anticipation is important. In this study, we examined the performance of linear discriminant analysis in continuous classification of straight-line walking, 45°changes of direction (crossover and sidestep cuts) and cuts to stair-ascent (i.e., “mixed” transitions), performed under varied anticipatory conditions of able-bodied individuals. Accelerographic and gyroscopic signals of the lower- and upper-body were used as signal inputs. Relatively high accuracy levels were observed during cut-to-stair, compared to cuts. In addition, classification of unanticipated maneuvers was compared for differing amounts of anticipated and unanticipated training data. It was observed that not more than two bouts of a given transition were needed to provide significant improvement in recognition of unanticipated mixed transitions. However, substantial (~5 bouts) unanticipated information was needed to deliver improved performance of cuts (without stair). This study has implications for enhancing the design of recognition systems that adapt to changes of direction and user cognition. These outcomes could inform robust handling of “unknown” circumstances and deliver an increased level of user safety and confidence.
Identifying TF Binding Motifs from a Partial Set of Target Genes and its Application to Regulatory Network Inference

Motif identification has been one of the most widely studied problems in bioinformatics. Many methods have been developed to discover binding motifs from a large set of genes. But when the given genes are only a partial set of target genes, the statistical significance usually contains a bias towards the input. If we can identify the TF binding motif from a partial set of target genes, we can save the labor costs and resources for doing many experiments. In this paper, we propose a method MISA (Motif Identification through Segments Assembly) to identify binding motifs from a subset of target genes. By ranking and assembling the segments, MISA discovers a set of binding motifs with the best length to fit our proposed objective function. We also predict the additional target genes as an application of regulatory network inference. We compare our approach with two widely used methods MEME and AlignACE by analyzing both the quality of the binding motif and network inference. Using two model organisms S. cerevisiae and E. coli , we show that with 20 percent of the target genes (minimum sample size of 20), we can achieve a motif similarity of 82 percent with the known motifs. Our results also show that 73 percent of target genes on average can be correctly predicted without introducing many false target genes.
Pairing nest boxes does not promote coexistence of Eastern Bluebirds (Sialia sialis) and subordinate cavity nesters

ABSTRACT Because nest site competition among cavity-nesting birds is often intense, the practice of pairing nest boxes has been promoted as a way to reduce nest-site competition and allow for the r...
THE IN SITU PHOSPHORYLATION OF THE α-SUBUNIT OF eIF-2 IN RETICULOCYTE LYSATES INHIBITED BY HEME DEFICIENCY, dsRNA, GSSG, OR THE HEME-REGULATED INHIBITOR

Publisher Summary This chapter analyzes in situ phosphorylation of the α-subunit of eIF-2 in reticulocyte lysates inhibited by heme deficiency, dsRNA, GSSG, or the heme-regulated inhibitor. The initiation of protein synthesis in reticulocyte lysates is inhibited in the absence of hemin, or in the presence of GSSG (50–500 μM) or dsRNA (1–50 ng/ml). All three conditions activate cAMP-independent protein kinases that phosphorylate the α-subunit (38,000 daltons) of eIF-2 (elF-2α). In this study, this phosphorylation is examined directly in lysates by labeling for brief periods with a pulse of high specific activity [γ-32P]ATP. The [32P]phosphoprotein profiles were analyzed by one-dimensional SDS-PAGE and autoradiography under conditions in which the eIF-2α polypeptide could be clearly distinguished. All modes of inhibition produced a rapid and significant increase in the phosphorylation of eIF-2α, compared to uninhibited control incubations which displayed little or no phosphorylation of eIF-2α. In heme-deficient lysates, phosphorylation of eIF-2α was detectable within 30 seconds after the start of incubation, and at all times subsequent both before and after the shut-off of protein synthesis. The restoration of synthesis by the delayed addition of hemin is accompanied by a decrease in the phosphorylation of eIF-2α.
Associations between frequency of cigarette and alternative tobacco product use and depressive symptoms: A longitudinal study of young adults.

Abstract The association between cigarette use and depression has been documented in many studies. Fewer studies have examined other tobacco products such as electronic cigarettes (e-cigarettes) and hookah that are used by young adults. This study examined whether increased frequency of use of these products was associated with depressive symptoms in a cohort of n = 5236 Texas college students followed from 2014 to 2017. To analyze the longitudinal data, a hierarchical model was used. Model results showed that increased frequency of single product use of cigarettes, refillable e-cigarettes and hookah was associated with depressive symptoms. Refillable and disposable e-cigarettes were examined separately and results did not provide evidence of a different association for each type of e-cigarette when cigarettes were not also used. Dual use of cigarettes with another product was also examined. Dual use was associated with higher depressive symptoms for most product combinations. However, infrequent dual use of disposable e-cigarettes and cigarettes may not be associated with depressive symptoms. Suggestions for further research are included.
Selenium Nanoparticle Protection of Fibroblast Stress: Activation of ATF4 and Bcl-xL Expression

Background In recent years, selenium nanostructures have been researched due to their antibacterial properties, low toxicity to mammalian cells, and high biological efficacy. However, the clinical implementation of the use of selenium has received mixed results, and there is much work needed to improve the understanding of the biological mechanisms involved in the observed cellular responses. Materials and methods In this work, an investigation into the mechanistic pathways of selenium nanoparticles (SeNPs) in biological systems was conducted by studying the changes in gene expression of ATF4, Bcl-xL, BAD2, HSP70, and SOD2 in non-cancerous human dermal fibroblasts (HDF) under oxidative stress, nutrient deprivation stress, and no treatment (control) conditions. Results This study revealed that SeNP incubation led to reduced internal reactive oxygen species (ROS) generation for all conditions tested, thus, providing a protective environment for HDF. At the stress conditions, the expression of ATF4 and Bcl-xL increased for cells treated with SeNP incubation, leading to attenuation of the cells under stress. These results also hint at reductive stress causing a detrimental impact to cell proliferation under routine cell passaging conditions. Conclusion In summary, this study highlights some possible mechanistic pathways implicated in the action of SeNPs that warrant further investigation (specifically, reducing stress conditions for HDF) and continues to support the promise of SeNPs in a wide range of medical applications.
Fluid therapy and hemodynamic support in septic shock

Sepsis remains one of the leading causes of mortality in children all over the world, especially in the developing nations. Early recognition of sepsis and septic shock facilitate the resuscitation, further reducing the morbidity and mortality related to septic shock in children.Current evidence and guidelines emphasize on goal-directed therapy and institution-specific bundles in the management of septic shock in children. There is an emerging evidence for the use of newer monitoring and therapeutic modalities in the various phases of septic shock in children - especially the de-resuscitation phase, which need validation by further trials.
Logophoricity, Perspective, and Reflexives

The notion of logophoricity is used to characterize linguistic elements sensitive to perspective. The goal of this review is to examine this notion by focusing on the behavior of so-called exempt r...
Share Withholding in Blockchain Mining

Cryptocurrency achieves distributed consensus using proof of work or PoW. Prior research in blockchain security identified financially incentivized attacks based on withholding blocks which have the attacker compromise a victim pool and pose as a PoW contributor by submitting the shares (earning credit for mining) but withholding the blocks (no actual contributions to the pool). We advance such threats to generate greater reward advantage to the attackers while undermining the other miners and introduce the share withholding attack (SWH). SWH withholds shares to increase the attacker’s reward payout within the pool, in contrast to the prior threats withholding blocks focusing on the inter-pool dynamics. SWH rather builds on the block-withholding threats in order to exploit the information about the impending block submission timing, challenging the popularly established assumption that the block submission time is completely random and unknown to miners. We analyze SWH’s incentive compatibility and the vulnerability scope by identifying the critical systems and environmental parameters which determine the attack’s impact. Our results show that SWH yields unfair reward advantage at the expense of the protocol-complying victim miners and that a rational miner will selfishly launch SWH to maximize its reward profit. We inform the blockchain and cryptocurrency research of the SWH threat to facilitate further research and development to secure the blockchain consensus protocol.
Adaptive Partitioning for Coordinated Multi-agent Perimeter Defense

Multi-Robot Systems have been recently employed in different applications and have advantages over single-robot systems, such as increased robustness and task performance efficiency. We consider such assemblies specifically in the scenario of perimeter defense, where the task is to defend a circular perimeter by intercepting radially approaching targets. Possible intruders appear randomly at a fixed distance from the perimeter and with azimuthal location determined by some unknown probability density. Coordination among multiple defenders is a complex combinatorial optimization problem. In this work, we focus on the following two aspects: (i) estimating the probability density that describes the direction from which the next intruders are going to arrive, and (ii) partitioning of the space so that the defenders focus on capturing a disjoint subset of intruders. Results show that the proposed strategy increases the number of captures over a naive baseline strategy, especially in scenarios with non-uniform spatial distributions of intruder arrival. The proposed approach is also efficient and able to quickly adapt to time-varying intruder distributions.
Dipolar interactions in bilayers of indirect excitons

We studied both experimentally and theoretically attractive dipolar interaction in bilayers of indirect excitons (IXs) with built-in dipole moments and found monotonic IX energy reduction with density and spatial attraction between IX clouds.
Dual Immersion as Multicultural Education: A Reflection on Cross-cultural Research

In this chapter, I employ a cross-cultural perspective to conduct a reflexive analysis of the impact of researcher characteristics on gathering data in an elementary dual language immersion program. The chapter highlights how the intersection of race, culture, and language influenced the author’s social interactions with parents and teachers of Mandarin immersion programs. The analysis relies on year-long participant observations and prior interviews with African-American parents, in California. First, I highlight my own background and the path that led me to this research. Then, I identify various perspectives and challenges that arise when different cultures converge. Finally, by drawing a connection between my personal experience and my research, I contend that language immersion programs should be placed within a multicultural education framework.
Using Model Selection Criteria to Choose the Number of Principal Components

The use of information criteria, especially AIC (Akaike’s information criterion) and BIC (Bayesian information criterion), for choosing an adequate number of principal components is illustrated.
Coherent spin transport in a natural metalloprotein molecule

Recently, the long-range spin-selective transport in chiral molecules has been investigated for bio-spintronics. The experimental results for a natural metalloprotein molecule suggested a high spin selectivity. I performed first-principle calculations of electron spin transport in a natural metalloprotein molecule based on the Landauer formula. A gold–metalloprotein–gold device model was used to confirm the high spin polarization. There was a relatively large spin density at some amide groups in the helical peptide structures. Furthermore, a large spin density of iron atoms enhanced the spin density of the neighboring coordinated atoms, resulting in spin polarization in the whole molecule.
Protein synthesis by rat intestinal mucosa. The role of ribonuclease.

Abstract Protein synthesis in rat intestinal mucosal cells has been studied in slices and subcellular fractions. Intestinal cells incorporated 14C-l-leucine into protein at rates comparable to that of liver. However, homogenates of intestine were inactive in protein synthesis. It was found that polyribosomes could not be isolated from intestinal mucosa without the use of methods to diminish ribonuclease activity. The jejunal mucosa was found to contain more soluble ribonuclease activity than ileal mucosa. This increase in activity could be eliminated by prior ligation of the common bile duct, thereby reducing intraluminal pancreatic enzymes. Tissue slices from the jejunum incorporated less 14C-l-leucine into protein than ileal slices, and this difference appeared to be explained, at least in part, by the difference in mucosal ribonuclease activity. Ribonuclease was found to be absorbed by the intestine into the portal vein in small but nevertheless significant amounts. It is concluded that in the rat ribonuclease can be absorbed by the intact intestine, and can modify the function of intestinal cells in vitro as well as the structure and function of isolated ribosomes.
Aggression Escalated by Social Instigation or by Discontinuation of Reinforcement (“Frustration”) in Mice ☆: Inhibition by Anpirtoline: A 5-HT1B Receptor Agonist

Experiments with social instigation or the omission of scheduled reinforcement show that serotonergic mechanisms may be involved in escalated aggression in animals. 5-HT1B receptor agonists have anti-aggressive effects in individuals who show moderate as well as high levels of aggression. The present study compared the effects of the 5-HT1B agonist anpirtoline (0.125–1.5 mg/kg) on (1) species-typical aggressive behavior in male mice, (2) aggression “instigated” or primed by prior exposure to the opponent, and (3) aggression heightened by “frustration” caused by omission of scheduled reinforcement. The effects of anpirtoline on species-typical behavior were also assessed after pretreatment with the 5-HT1B/1D receptor antagonist GR127935 (10 mg/kg). Anpirtoline, like other 5-HT1B agonists (CP-94,253, zolmitriptan), decreased both instigated and frustration-heightened aggression, while motor behavior was unaffected. The aggression-inhibiting effects of anpirtoline were blocked by pretreatment with GR127935. The current results indicate that the 5-HT1B receptor is critically involved in the modulation of escalated aggression.
On Embedded Languages, Meta-Level Reasoning, and Computer-Aided Modeling

We discuss the role of meta-level reasoning in developing programs that can reason both within and about some domain. In particular, we discuss why meta-level reasoning is useful, and essentially required, in developing computer-based modeling systems that can provide meaningful support to modelers throughout the modeling life cycle. We then describe a general technique, which we call the embedded languages technique, for constructing systems that do meta-level reasoning. Finally, we describe how the embedded languages technique may be used in developing an advanced computer-aided modeling environment.
Radiation in a Closed 3-D Universe Reveals its Present Geometry and its Past Evolution

In previous papers, predictions of the new "Spatial Condensation (SC-)" cosmological model were presented on the (1) foundations, (2) new source of gravity, and (3) large-scale structure. In this paper predictions will include new physical features that are due mostly to the postulated geometry of our closed 3-D universe. Knowledge of the past universe is obtained from its many types of radiation that travel to our instruments on great circles of our expanding 3-sphere. Adding the fourth spatial dimension greatly increases our understanding of the concepts of emission and reception distances of the sources and 4-D trajectory of the radiation. In a closed expanding 3-D universe, most of the radiation from a distant bright source at Ze can travel halfway around the universe and be refocused as a "virtual source" at Zv ~1.5 where some of the re-diverging radiation arrives later to our instruments. With the added fourth dimension, the SC-model makes some spectacular predictions for these virtual sources. Indeed, the CBR becomes a re-focused "backside" microwave radiation with its structure amplified in size and decreased in luminosity by a factor ~ 1/350. "Viewed" in the optical from a direction opposite the CBR, the same, but more evolved, structure at "virtual Zsame" would certainly fix the geometry and size of our universe. Virtual sources are also added radiation to the diffuse background of X-rays and infrared. The CBR dipole suggests a preferred reference frame. Reflected light signals in a non-accelerated frame show, in principle, the moving frame could be brought to rest in the comoving frame.
Emotions in Justice Processes

Emotions contribute to how individuals and groups make sense out of their experiences of (in) justice. Classic justice approaches typically cast emotions as a response to perceived (distributive, procedural, and interactional) injustice, which in turn influences behavioral reactions. More recent work recognizes affect as a potential antecedent to the experience of injustice as well as stresses the dynamic relationship between cognitions, emotions, and behavior. Consideration of such dynamics draws attention to the context of the experience of injustice and the role of observers or third parties who do not similarly suffer injustice. This chapter examines basic definitions and theoretical tenets of justice perspectives that address the role of emotions and reviews individual and group-level empirical patterns. The conclusion specifies theoretical directions and empirical pathways, highlighting the complexity of emotions in justice processes.
Plant species diversity on logged versus burned sites in central Alaska

Natural fires and logging are two of the main disturbances affecting upland boreal forest in Alaska. The objectives of this study were to determine whether logged sites differ from burned sites in (1) overall plant species richness, (2) successional trajectories, and (3) species diversity at particular stand structural development stages. We compared plant species diversity on sites burned in natural fires to sites that were logged and not subsequently burned in central Alaska. We sampled 12 logged and 12 burned former upland white spruce (Picea glauca (Moench) Voss) forests in four stand development stages representing stand initiation (stage A), early stem exclusion (stage B), understory reinitiation (stage C), and mature hardwood (stage D) stages. In this study the dates of disturbance varied from 1990 to 1994 in stage A, 1978 to 1983 in stage B, 1957 to 1965 in stage C, and 1900 to 1920 in stage D plots. All sites were similar in slope, aspect, and soil type. Vascular plants were identified to the species level (except for certain willows) and bryophytes and lichens were identified to the level of presumptive (usually unknown) species within family groups. Organic layer thickness was significantly greater on logged sites compared to burned sites overall and at each stage. Burned sites (all stages combined) supported more species (146) than logged sites (111), and more species at each stand development stage. Burned plots in stages A and B supported abundant cover of a few apparent fire specialist species (Ceratodon purpureus (Hedw.) Brid., Marchantia polymorpha L. and Leptobryum pyriforme (Hedw.) Wils.) that were present in only minor amounts on logged sites. Burned plots exhibited higher species turnover from stage to stage and among all stages than logged plots. Species dominant in burned stage A plots were nearly absent in burned stage C and D plots, while logged stage A dominants, which were common mature forest species, increased in each subsequent stage. We compared floristic similarity between our disturbance plots and mature upland white spruce stands in Bonanza Creek Long-Term Ecological Research (LTER) site. Only five species found in the LTER dataset were not also present in this study, which suggests that nearly all species compositional change in our study area occurs during the first century after disturbance. Logged sites appear to begin and continue succession with a greater share of the original mature forest understory plants, while burned sites initiate succession with more distinctive and specialized plant species.
Old phage, new insights: Two recently recognized mechanisms of transcriptional regulation in bacteriophage T4 development

The regulation of bacteriophage T4 middle and late gene expression involves previously unrecognized mechanisms. Middle transcription requires a DNA-binding transcriptional activator and a σ70-binding co-activator. The coupling of late transcription to DNA replication is effected by a DNA-tracking protein that is loaded onto DNA by an assembly factor at enhancer-like entry sites. Late transcription also requires an RNA polymerase core-binding co-activator. The co-activators of T4 middle and late transcription share the property of depressing unactivated, basal transcription.
Effects of DBS on precision grip abnormalities in essential tremor.

Deep brain stimulation (DBS) of the ventrolateral thalamus is a highly effective procedure for the treatment of essential tremor (ET). The regularity of repetitive, self-paced finger tapping is known to be abnormal in patients with ET and improved following DBS. However, the more complex timing that underlies force development in the hands in ET and after DBS has not been evaluated. In this pilot study, we assessed precision grip performance in seven ET subjects before and after 5 months of DBS. Ten healthy controls were also studied. ET subjects showed a significant increase in preload duration (235 ± 145 vs. 82 ± 49 ms) and peak negative load (−0.524 ± 0.35 vs. −0.174 ± 0.14 N) during grip–lift compared with healthy subjects. No difference in load duration was observed between the groups. Following DBS, the magnitude of the peak negative load was significantly reduced (P = 0.03). In contrast, the duration of the load phase was worsened (non-significant) after DBS. We conclude that defects in the control of distal musculature necessary for establishing a stable grip exist in ET, whereas proximal muscles necessary for object lift-off remain relatively intact. Further, synergy paradigms governing grip–lift coordination may also be impaired. Although DBS is successful in alleviating tremor in ET, it produces only a partial restoration of normal precision grip.
Permeabilization of Streptococcus thermophilus and the expression of beta-galactosidase

Studies were carried out to determine the efficacy of several permeabilizing agents in inducing high-level expression of β-galactosidase in Streptococcus thermophilus. Sodium dodecyl sulfate, Triton X-100, sodium deoxycholate, and one commercial bile acid preparation were effective as membrane destabilizing agents allowing lactose influx and hydrolysis by cytoplasmic β-galactosidase in treated cells. Cells exposed to Oxgall or Triton X-100 displayed 15 times higher levels of β-galactosidase activity than control cells. Detergent treatment also induced extensive cell death or significant injury to cell populations resulting in long delays before resumption of growth. A permeabilized suspension of S. thermophilus corresponding to 108 cfu ml−1 released 87% of glucose available in a 5% lactose solution within 10 min at 50°;C.
Dependence balance outer bounds for the discrete memoryless two-way multiple access broadcast channel

We present an outer bound for the discrete memo-ryless two-way multiple access broadcast channel (TW-MAC/BC) using the dependence balance idea. The cut-set outer bound for multi-user channels allows arbitrarily correlated input distributions while the dependence balance idea limits the set of arbitrarily correlated input distributions to those satisfying a specific constraint known as dependence balance bound, which is particularly useful in channels with feedback or adaptation, as in two-way channels. We obtain a general dependence-balance-based outer bound for the discrete memoryless TW-MAC/BC, and a parallel channel extension for the single-output channel. We then show that for the single-output binary additive noisy TW-MAC/BC Y = X 1 + X 2 + X 3 + Z (Z Bernoulli(0.5)), an outer bound to the symmetric sum-rate of our outer bound is strictly smaller than that of the cut-set outer bound. This is shown using the composite function technique introduced by Willems and used by Tandon and Ulukus in the context of multiple-access channels with feedback.
An indirect technique for fabrication of a post and core wax pattern

Indirect techniques for the fabrication of posts and cores provide some advantages over direct techniques. Indirect fabrication allows parallelism and design to be optimized. This becomes particularly important when multiple abutments are prepared. The laboratory technique, however, can create some difficulties. Posts fabricated with acrylic resin may become locked into minor cast undercuts.1 Use of wax for the post fabrication reduces this problem, but insertion and removal of the pattern during its fabrication are required.2 Although this reduces the inclusion of voids, insertion and removal may create distortion or breakage of the wax pattern. It is also difficult to orient the post correctly each time. The following procedure provides a predictable method of delivering wax to the canal and eliminates the need for removal and insertion of the pattern during fabrication.