Miracle-dz/UniFAR-FTUs huggingface dataset:
The Grothendieck Constant is Strictly Smaller than Krivine's Bound

The classical Grothendieck constant, denoted $K_G$, is equal to the integrality gap of the natural semi definite relaxation of the problem of computing$$\max \{\sum_{i=1}^m\sum_{j=1}^n a_{ij} \epsilon_i\delta_j: \{\epsilon_i\}_{i=1}^m,\{\delta_j\}_{j=1}^n\subseteq \{-1,1\}\},$$a generic and well-studied optimization problem with many applications. Krivine proved in 1977 that $K_G\leq \pi / (2\log(1+\sqrt{2}))$ and conjectured that his estimate is sharp. We obtain a sharper Grothendieck inequality, showing that $K_G 0$. Our main contribution is conceptual: despite dealing with a binary rounding problem, random 2-dimensional projections combined with a careful partition of $R^2$ in order to round the projected vectors, beat the random hyper plane technique, contrary to Krivine's long-standing conjecture.
Giardia lamblia in patients undergoing upper G.I. endoscopy.

To determine the frequency of giardiasis in patients undergoing upper G.I. endoscopy for dyspepsia and other upper G.I. disorders, duodenal aspirates were collected in 200 patients and simultaneous duodenal biopsies in 163 patients. Nine percent aspirates and 1.8% duodenal biopsies showed Giardia lamblia trophozoites. Giardia as a cause of dyspepsia should be considered in patients with negative endoscopy and in those who remain symptomatic inspite of adequate treatment for known upper G.I. disorders.
Recognizing child's emotional state in problem-solving child-machine interactions

The need for automatic recognition of a speaker's emotion within a spoken dialog system framework has received increased attention with demand for computer interfaces that provide natural and user-adaptive spoken interaction. This paper addresses the problem of automatically recognizing a child's emotional state using information obtained from audio and video signals. The study is based on a multimodal data corpus consisting of spontaneous conversations between a child and a computer agent. Four different techniques-- k-nearest neighborhood (k-NN) classifier, decision tree, linear discriminant classifier (LDC), and support vector machine classifier (SVC)-- were employed for classifying utterances into 2 emotion classes, negative and non-negative, for both acoustic and visual information. Experimental results show that, overall, combining visual information with acoustic information leads to performance improvements in emotion recognition. We obtained the best results when information sources were combined at feature level. Specifically, results showed that the addition of visual information to acoustic information yields relative improvements in emotion recognition of 3.8% with both LDC and SVC classifiers for information fusion at the feature level over that of using only acoustic information.
A Work-System Approach to Classifying Risks in Crowdfunding Platforms: An Exploratory Analysis

Crowdfunding has attracted much attention in the last few years because it has opened up new pathways for projects to obtain financing from individuals who are non-professional investors via the Internet. While risk occupies a central role in crowdfunding, this notion has been an unexplored area in the information systems literature. To close this gap, we contribute to the literature by identifying the main risks in crowdfunding platforms. Using the Work Systems Risk Framework, we analyze main risks in three equity crowdfunding platforms: Crowdfunder, AngelList and Seedrs. Our findings indicate that operational risk, project management risk, cognitive skill risk, IP risk, quality risk, legal risk and vendor relationship risk factors to be important to crowdfunding platforms. Findings from this study are relevant to platform owners and regulators in assessing the risks of crowdfunding platforms.
Optimal Retransmission Probability for S-ALOHA Under the Infinite Population Model

In this paper, a mathematical analysis method to simultaneously evaluate throughput and access delay considering an infinite population model is considered. Most of the previous related research has been done considering both finite population and saturation conditions where all the nodes in the system have always a packet ready to be transmitted and the transmission queue of each station is assumed to be always nonempty. This assumption is a good approximation for a local area network working at full capacity; however, in a cellular system the assumptions of finite population and that every node in a cell has always a packet to transmit is not very realistic. Here, analytical results considering a S-ALOHA random access protocol with a Poisson arrival process - more suitable for the traffic model in a cellular system - for the users in the cells is presented. Using the geometrical backoff (GB) strategy, two approaches to find the optimum retransmission probabilities are developed; in the first one, the number of backlogged packets is required while a simpler and efficient alternative method requires only the knowledge of the new packet arrival rate.
Hemodynamic Evaluation of Embolic Trajectory in an Arterial Bifurcation: An In-Vitro Experimental Model

Background and Purpose— Despite the importance of embolism as a major cause of brain infarction, little is known about the hemodynamic factors governing the path large emboli tend to follow. Our aim was to test in vitro, whether hemodynamic parameters other than flow ratios between bifurcation branches may affect the distribution of embolic particles in a Y-shaped bifurcation model, used as an analogue to an arterial bifurcation. Methods— In vitro experiments were conducted using suspensions of sphere-shaped particles (0.6, 1.6, and 3.2 mm) in water-glycerin mixture, using steady and pulsatile laminar flow regimes in a Y-shaped bifurcation model (identical branching angles [&thgr;1=&thgr;2=45o] with one daughter branch diameter wider than the other [D1=6 mm, D2=4 mm]; average Reynolds number 500). Results— Experiments using naturally buoyant particles under steady flow conditions and four outlet-flow ratios revealed that small (0.6 mm) and mid-sized (1.6 mm) particles entered into either the narrower or wider bifurcation daughter branch nonpreferentially, proportionally to the flow ratios. Large particles (3.2 mm), however, preferentially entered the wider daughter branch. Moreover, as the flow ratio increases this phenomenon was augmented. Further experiments revealed that the preference of the wider daughter branch for high particle-to-branch diameter-ratios further increases under pulsatile flow and by the density ratio between particles and fluid. Conclusion— Particles’ distribution in a bifurcation is affected, beyond its outlets-flow-ratios, by the particle-to-branch diameter-ratio. The tendency of large particles to preferentially enter the wider bifurcation branch, beyond the flow ratio, is augmented under pulsatile flow conditions and is affected by particle-to-fluid density-ratio. These findings may have important implications for understanding the hemodynamic mechanisms underlying the trajectory of large emboli.
Tactile Assessment in Children with Cerebral Palsy: A Clinimetric Review

ABSTRACT This review evaluates the clinimetric properties of tactile assessments for children with cerebral palsy. Assessment of registration was reported using Semmes Weinstein Monofilaments (SWMs) or exteroception. Assessment of two-point discrimination was reported using the Disk-Criminator® or paperclip methods; Single point localization and double simultaneous were reported from the Neurosensory Motor Developmental Assessment (NSMDA); graphaesthesia was reported from the Sensory Integration and Praxis Test (SIPT); and stereognosis was assessed using Manual Form Perception from the SIPT and the Klingels method (Klingels, K. et al. (2010). Upper limb motor and sensory impairments in children with hemiplegic cerebral palsy. Can they be measured reliably? Disability and Rehabilitation, 32(5), 409–416) and the Cooper method (Cooper, J., Majnemer, A., Rosenblatt, B., & Birnbaum, R. (1995). The determination of sensory deficits in children with hemiplegic cerebral palsy. Journal of Child Neurology, 10, 300–309). The SIPT and NSMDA demonstrated stronger content validity. Inter-rater reliability was excellent for SIPT (ICC = 0.99) and exteroception (k = 0.88). Test–retest reliability was excellent for exteroception (k = 0.89) and stereognosis (ICC = 0.86; 100%), moderate for SIPT (r = 0.69–0.74) and poor for SWM (k = 0.22). Together these assessments measure tactile registration and spatial perception. Temporal and textural tests are to be developed for comprehensive tactile examination.
Small-Ruminant Lentivirus Enhances PrPSc Accumulation in Cultured Sheep Microglial Cells

ABSTRACT Sheep scrapie is the prototypical transmissible spongiform encephalopathy (prion disease), which has a fundamental pathogenesis involving conversion of normal cellular prion protein (PrPC [C superscript stands for cellular]) to disease-associated prion protein (PrPSc [Sc superscript stands for sheep scrapie]). Sheep microglial cell cultures, derived from a prnp 136VV/171QQ near-term fetal brain, were developed to study sheep scrapie in the natural host and to investigate potential cofactors in the prion conversion process. Two culture systems, a primary cell culture and a cell line transformed with the large T antigen of simian virus 40, were developed, and both were identified as microglial in origin as indicated by expression of several microglial phenotype markers. Following exposure to PrPSc, sheep microglial cells demonstrated relatively low levels (transformed cell line) to high levels (primary cell line) of PrPSc accumulation over time. The accumulated PrPSc demonstrated protease resistance, an inferred beta-sheet conformation (as determined by a commercial enzyme-linked immunosorbent assay), specific inhibition by anti-PrP antibodies, and was transmissible in a dose-dependent manner. Primary microglia coinfected with a small-ruminant lentivirus (caprine arthritis encephalitis virus-Cork strain) and PrPSc demonstrated an approximately twofold increase in PrPSc accumulation compared to that of primary microglia infected with PrPSc alone. The results demonstrate the in vitro utility of PrPSc-permissive sheep microglial cells in investigating the biology of natural prion diseases and show that small-ruminant lentiviruses enhance prion conversion in cultured sheep microglia.
Role of iodine in antioxidant defence in thyroid and breast disease

The role played in thyroid hormonogenesis by iodide oxidation to iodine (organification) is well established. Iodine deficiency may produce conditions of oxidative stress with high TSH producing a level of H2O2, which because of lack of iodide is not being used to form thyroid hormones. The cytotoxic actions of excess iodide in thyroid cells may depend on the formation of free radicals and can be attributed to both necrotic and apoptotic mechanisms with necrosis predominating in goiter development and apoptosis during iodide induced involution. These cytotoxic effects appear to depend on the status of antioxidative enzymes and may only be evident in conditions of selenium deficiency where the activity of selenium containing antioxidative enzymes is impaired. Less compelling evidence exists of a role for iodide as an antioxidant in the breast. However the Japanese experience may indicate a protective effect against breast cancer for an iodine rich seaweed containing diet. Similarly thyroid autoimmunity may also be associated with improved prognosis. Whether this phenomenon is breast specific and its possible relationship to iodine or selenium status awaits resolution.
Impaired tissue regeneration corresponds with altered expression of developmental genes that persists in the metabolic memory state of diabetic zebrafish

As previously reported by our laboratory, streptozocin‐induced diabetes mellitus (DM) in adult zebrafish results in an impairment of tissue regeneration as monitored by caudal fin regeneration. Following streptozocin withdrawal, a recovery phase occurs to reestablish euglycemia, via pancreatic beta‐cell regeneration. However, DM‐associated impaired fin regeneration continues indefinitely in the metabolic memory (MM) state, allowing for subsequent molecular analysis of the underlying mechanisms of MM. This study focuses on elucidating the molecular basis that explains the DM‐associated impaired fin regeneration and why it persists into the MM state with the aim of better understanding MM. Using a combination of microarray analysis and bioinformatics approaches, our study found that of the 14,900 transcripts analyzed, aberrant expression of 71 genes relating to tissue developmental and regeneration processes were identified in DM fish and the altered expression of these 71 genes persisted in MM fish. Key regulatory genes of major development and signal transduction pathways were identified among this group of 71. The aberrant expression of key regulatory genes in the DM state that persist into the MM state provides a plausible explanation on how hyperglycemia induced impaired fin regeneration in the adult zebrafish DM/MM model.
Mutable checkpoint-restart: automating live update for generic server programs

The pressing demand to deploy software updates without stopping running programs has fostered much research on live update systems in the past decades. Prior solutions, however, either make strong assumptions on the nature of the update or require extensive and error-prone manual effort, factors which discourage live update adoption. This paper presents Mutable Checkpoint-Restart (MCR), a new live update solution for generic (multiprocess and multithreaded) server programs written in C. Compared to prior solutions, MCR can support arbitrary software updates and automate most of the common live update operations. The key idea is to allow the new version to restart as similarly to a fresh program initialization as possible, relying on existing code paths to automatically restore the old program threads and reinitialize a relevant portion of the program data structures. To transfer the remaining data structures, MCR relies on a combination of precise and conservative garbage collection techniques to trace all the global pointers and apply the required state transformations on the fly. Experimental results on popular server programs (Apache httpd, nginx, OpenSSH and vsftpd) confirm that our techniques can effectively automate problems previously deemed difficult at the cost of negligible run-time performance overhead (2% on average) and moderate memory overhead (3.9x on average).
Diffusive Transport through a Nontwist Barrier in tokamaks

The magnetic field line structure of tokamaks with reversed magnetic shear is analyzed by means of a nontwist map model that takes into account non-integrable perturbations that describe ergodic magnetic limiters. The map studied possess behavior expected of the standard nontwist map, a well-studied map, despite the different symmetries and the existence of coupled perturbations. A distinguising feature of nontwist maps is the presence of good surfaces in the reveresed shear region, and consequently the appearance of a transport barrier inside the plasma. Such barriers are observed in the present model and are seen to be very robust. Very strong perturbations are required to destroy them, and even after breaking, the transport turns out to be diffusive. Poloidal diffusion is found to be two orders of magnitude higher than radial diffusion.
The genetically encoded tool set for investigating cAMP: more than the sum of its parts

Intracellular fluctuations of the second messenger cyclic AMP (cAMP) are regulated with spatial and temporal precision. This regulation is supported by the sophisticated arrangement of cyclases, phosphodiesterases, anchoring proteins, and receptors for cAMP. Discovery of these nuances to cAMP signaling has been facilitated by the development of genetically encodable tools for monitoring and manipulating cAMP and the proteins that support cAMP signaling. In this review, we discuss the state-of-the-art in development of different genetically encoded tools for sensing cAMP and the activity of its primary intracellular receptor protein kinase A (PKA). We introduce sequences for encoding adenylyl cyclases that enable cAMP levels to be artificially elevated within cells. We chart the evolution of sequences for selectively modifying protein–protein interactions that support cAMP signaling, and for driving cAMP sensors and manipulators to different subcellular locations. Importantly, these different genetically encoded tools can be applied synergistically, and we highlight notable instances that take advantage of this property. Finally, we consider prospects for extending the utility of the tool set to support further insights into the role of cAMP in health and disease.
Regulatory mechanisms of the acrosome reaction revealed by multiview microscopy of single starfish sperm

The acrosome reaction in many animals is a coupled reaction involving an exocytotic step and a dramatic change in cell shape. It has been proposed that these morphological changes are regulated by intracellular ions such as Ca2+ and H+. We report here simultaneous visualization, under a multiview microscope, of intracellular free Ca2+ concentration ([Ca2+]i), intracellular pH (pHi), and morphological changes in a single starfish sperm (Asterina pectinifera). [Ca2+]i and pHi were monitored with the fluorescent probes indo-1 and SNARF-1, respectively. The acrosome reaction was induced with ionomycin. After the introduction of ionomycin in the medium, [Ca2+]i increased gradually and reached a plateau in approximately 30 s. The fusion of the acrosomal vacuole took place abruptly before the plateau, during the rising phase. Although the speed of the [Ca2+]i increase varied among the many sperm tested, exocytosis in all cases occurred at the same [Ca2+]i of approximately 2 microM (estimated using the dissociation constant of indo-1 for Ca2+ of 1.1 microM). This result suggests that the exocytotic mechanism in starfish sperm responds to [Ca2+]i rapidly, with a reaction time of the order of one second or less. Unlike the change in [Ca2+]i, an abrupt increase in pHi was observed immediately after exocytosis, suggesting the presence of a proton mobilizing system that is triggered by exocytosis. The rapid increase in pHi coincided with the formation of the acrosomal rod and the beginning of vigorous movement of the flagellum, both of which have been proposed to be pHi dependent. The exocytotic event itself was visualized with the fluorescent membrane probe RH292. The membrane of the acrosomal vacuole, concealed from the external medium in an unreacted sperm, was seen to fuse with the plasma membrane.
Enhancement of recovery of Neisseria meningitidis by gelatin in blood culture media

The efficacy of gelatin for the recovery of Neisseria meningitidis from blood cultures was evaluated in a clinical setting. The organism was isolated from seven patients with meningococcal infections in blood culture media containing 1% gelatin. In contrast, only two blood cultures from these patients were positive in media without gelatin (P less than 0.05). Gelatin did not influence the recovery of other organisms isolated during this study. Conventional blood culture media may be supplemented with gelatin when meningococcemia is suspected.
Interactions and fates of avian craniofacial mesenchyme.

Craniofacial mesenchyme is composed of three mesodermal populations - prechordal plate, lateral mesoderm and paraxial mesoderm, which includes the segmented occipital somites and the incompletely segmented somitomeres - and the neural crest. This paper outlines the fates of each of these, as determined using quail-chick chimaeras, and presents similarities and differences between these cephalic populations and their counterparts in the trunk. Prechordal and paraxial mesodermal populations are the sources of all voluntary muscles of the head. The latter also provides most of the connective precursors of the calvaria, occipital, otic-parietal and basisphenoid tissues. Lateral mesoderm is the source of peripharyngeal connective tissues; the most rostral skeletal tissues it forms are the laryngeal and tracheal cartilages. When migrating neural crest cells encounter segmented paraxial mesoderm (occipital and trunk somites), most move into the region between the dermamyotome and sclerotome in the cranial half of each somite. In contrast, most cephalic crest cells migrate superficial to somitomeres. There is, however, a small subpopulation of the head crest that invades somitomeric mesoderm. These cells subsequently segregate presumptive myogenic precursors of visceral arch voluntary muscles from underlying mesenchyme. In the neurula-stage avian embryo, all paraxial and lateral mesodermal populations contain precursors of vascular endothelial cells, which can be detected in chimaeric embryos using anti-quail endothelial anti-bodies. Some of these angioblasts differentiate in situ, contributing directly to pre-existing vessels or forming isolated, nonpatent, cords that subsequently vesiculate and fuse with nearby vessels. Many angioblasts migrate in all directions, invading embryonic mesenchymal and epithelial tissues and participating in new blood vessel formation in distant sites. The interactions leading to proper spatial patterning of craniofacial skeletal, muscular, vascular and peripheral neural tissues has been studied by performing heterotopic transplants of each of these mesodermal and neural crest populations. The results consistently indicate that connective tissue precursors, regardless of their origin, contain spatial information used by the precursors of muscles and blood vessels and by outgrowing peripheral nerves. Some of these connective tissue precursors (e.g. the neural crest, paraxial mesoderm) acquire their spatial programming while in association with the central nervous system or developing sensory epithelia (e.g. otic, optic, nasal epithelia).