Miracle-dz/UniFAR-FTUs huggingface dataset:
Optimization Based Topology Control for Wireless Ad Hoc Networks to Meet QoS Requirements

This paper proposes a technique for topology control (TC) of wireless nodes to meet Quality of Service (QoS) requirements between source and destination node pairs. The nodes are assumed to use a TDMA (Time Division Multiple Access) based MAC (Medium Access Control) layer. Given a set of QoS requirements, a set of wireless nodes and their initial positions, the goal is to find a topology of the nodes by adjusting the transmitting power, which will meet the QoS requirements under the presence of interference and at the same time minimize the energy consumed. The problem of TC is treated like an optimization problem and techniques of Linear Programming (LP) and Genetic Algorithms (GA) are used to solve it. The solution obtained after solving the optimization problem is in the form of optimal routes to be followed between each source, destination node pair. This information is used to construct the optimal topology.
Developing technological pedagogical content knowledge in pre-service mathematics teachers through collaborative design

Although many studies have shown the need to pay attention to teachers' preparation for the integration of technology in classroom practice, most teachers in Ghana have not had any preparation that develops their technological pedagogical content knowledge (TPCK). This paper presents a case study of four pre-service mathematics teachers from the University of Cape Coast, Ghana, who worked in two design teams to develop lessons, and subsequently taught in a technology-based environment for the first time. It was evident from the findings that more systematic efforts are needed to engage pre-service teachers in technology-rich design activities, to develop their TPCK adequately. The study also showed the potential of TPCK as a new frame for developing pre-service teachers' experiences in technology integration within initial teacher education, particularly in Sub-Saharan African countries
Interpretations arising from Wrightian and Malthusian fitness under strong frequency dependent selection

Fitness is the central concept in evolutionary theory. It measures a phenotype's ability to survive and reproduce. There are different ways to represent this measure: Malthusian fitness and Wrightian fitness. One can go back and forth between the two, but when we characterize model properties or interpret data, it can be important to distinguish between them. Here, we discuss a recent experiment to show how the interpretation changes if an alternative definition is used.
Efficient IP-address lookup with a shared forwarding table for multiple virtual routers

Virtual routers are a promising way to provide network services such as customer-specific routing, policy-based routing, multi-topology routing, and network virtulization. However, the need to support a separate forwarding information base (FIB) for each virtual router leads to memory scaling challenges. In this paper, we present a small, shared data structure and a fast lookup algorithm that capitalize on the commonality of IP prefixes between each FIB. Experiments with real packet traces and routing tables show that our approach achieves much lower memory requirements and considerably faster lookup times. Our prototype implementation in the Click modular router, running both in user space and in the Linux kernel, demonstrates that our data structure and algorithm are an interesting solution for building scalable routers that support virtualization.
An Expository Development of a Mathematical Model of the Electoral Process

The fundamental process of politics is the aggregation of citizens' preferences into a collective—a social—choice. We develop, interpret, and explain non-technically in this expository essay the definitions, assumptions, and theorems of a mathematical model of one aggregative mechanism—the electoral process. This mechanism is conceptualized here as a multidimensional model of spatial competition in which competition consists of candidates affecting turnout and the electorate's perception of each candidate's positions, and in which the social choice is a policy package which the victorious candidate advocates. This approach, inaugurated by Downs's An Economic Theory of Democracy, and falling under the general rubric “spatial models of party competition,” has been scrutinized, criticized, and reformulated. To clarify the accomplishments of this formulation we identify and discuss in section 2 the general democratic problem of ascertaining a social preference. We review critically in section 3 the definitions and assumptions of our model. We consider in sections 4 and 5 the logic of a competitive electoral equilibrium. We assume in section 4 that the electorate's preferences can be summarized and represented by a single function; the analysis in section 5 pertains to competition between two organizational structures or two opposed ideologies (i.e., when two functions are required to summarize and represent the electorate's preference). Finally, we suggest in section 6 a conceptualization of electoral processes which facilitates extending and empirically testing our model.
Modular coherence of protein dynamics in yeast cell polarity system

In this study, we investigated on a systems level how complex protein interactions underlying cell polarity in yeast determine the dynamic association of proteins with the polar cortical domain (PCD) where they localize and perform morphogenetic functions. We constructed a network of physical interactions among >100 proteins localized to the PCD. This network was further divided into five robust modules correlating with distinct subprocesses associated with cell polarity. Based on this reconstructed network, we proposed a simple model that approximates a PCD protein's molecular residence time as the sum of the characteristic time constants of the functional modules with which it interacts, weighted by the number of edges forming these interactions. Regression analyses showed excellent fitting of the model with experimentally measured residence times for a large subset of the PCD proteins. The model is able to predict residence times using small training sets. Our analysis also revealed a scaffold protein that imposes a local constraint of dynamics for certain interacting proteins.
Normative Programs and Normative Mechanism Design (Extended Abstract)

The environment is an essential component of multi-agent systems, which is often used to coordinate the behaviour of individual agents. Recently many programming languages have been proposed to facilitate the implementation of such environments. This extended abstract is motivated by the emerging programming languages that are designed to implement environments in terms of normative concepts such as norms and sanctions. We propose a formal analysis of normative environment programs from a mechanism design perspective. By doing this we aim at relating normative environment programs to mechanism design, setting the stage for studying formal properties of these programs such as whether a set of norms implements a specific social choice function in a specific equilibria.
Surgery for herniated lumbar discs: a literature synthesis.

OBJECTIVE To assess the risks and benefits of surgery for herniated lumbar discs (discectomy) and to evaluate the methodologic quality of the literature. DESIGN Literature synthesis. STUDY SELECTION AND DATA ANALYSIS: A structured MEDLINE search identified studies of standard, microsurgical, or percutaneous discectomy. Eligible studies had adult subjects, sample sizes of > or = 30, clinical outcome data for > or = 75% of patients, and follow-up of > or = 1 year. Summary rates of successful outcomes, reoperations, and complications were obtained by a random-effects logistic regression model. Methodologic quality was assessed using established study design criteria. RESULTS Eighty-one studies met inclusion criteria. Most had substantial design flaws and/or omitted important clinical data. Randomized trials of standard discectomy showed better short-term sciatica relief following surgery; 65% to 85% of patients reported no sciatica one year after surgery, compared with only 36% of conservatively treated patients. No data from randomized trials were available for microdiscectomy or percutaneous discectomy, although most outcomes appeared comparable to those of standard discectomy. Approximately 10% of discectomy patients underwent further back surgery, and rates increased over time. The rate of serious complications, including death and permanent neurologic damage, was less than 1%. CONCLUSIONS Most studies were poorly designed and reported. Standard discectomy appears to offer better short-term outcomes than does conservative treatment, but long-term outcomes are similar. Discectomies are relatively safe procedures, though reoperations are common and increase over time. Decisions for elective surgery must balance faster pain relief against the risks and costs of surgery.
Barriers to Manipulation in Voting

Introduction In many situations, voters may vote strategically. That is, they may declare preferences that are not their true ones, with the aim of obtaining a better outcome for themselves. The following example illustrates this. Example 6.1. Consider an election with three alternatives, a , b , and c , and three voters, 1, 2, and 3. Suppose the rule used is plurality—an alternative gets a point each time it is ranked first by a voter, and the alternative with the most points wins—with ties broken toward alternatives earlier in the alphabet. Suppose voter 3 knows (or strongly suspects) that voter 1 will rank a first in her vote, and that voter 2 will rank b first. Voter 3's true preferences are c ≻ b ≻ a . If she votes truthfully, this will result in a three-way tie, broken in favor of a which is 3's least preferred alternative. If, instead, voter 3 ranks b first, then b will win instead. Hence, voter 3 has an incentive to cast a vote that does not reflect her true preferences. This is often referred to as manipulation or strategic voting ; we will use “manipulation” throughout. Voting rules that are never manipulable are also referred to as strategyproof . We start by reviewing the Gibbard-Satterthwaite impossibility result (discussed also in Chapter 2), which states that with unrestricted preferences over three or more alternatives, only very unnatural rules are strategyproof. The main focus of the chapter is on exploring whether computational complexity can be an effective barrier to manipulation. That is, we may not be concerned about manipulation of a voting rule if it is computationally hard to discover how to manipulate it. Gibbard-Satterthwaite and Its Implications An important axiomatic result about the properties of voting rules is the Gibbard- Satterthwaite Theorem: Theorem 6.2 (Gibbard, 1973; Satterthwaite, 1975). Consider a (resolute)votingrule that is defined for some number m of alternatives with m ≥ 3 , with no restrictionson the preference domain. Then, this rule must be at least one of the following: dictatorial : there exists a single fixed voter whose most-preferred alternative is chosenfor every profile; imposing: there is at least one alternative that does not win under any profile; manipulable (i.e., not strategyproof).
High Prevalence Disorders in Urban and Rural Communities

Objective: High prevalence disorders (anxiety, depressive and substance use) are generally assumed to be more common in urban than rural dwellers. The aims of this paper are (i) to critically review studies measuring prevalence in rural as opposed to urban location, and (ii) to argue the need to look beyond the ‘quantity’ question to the quality question: how does urban or rural place influence mental health? Method: A literature review (Medline and PsychLIT) was carried out using the words ‘rural, urban, mental/psychiatric, illness/disorders and prevalence’, as well as a review of relevant papers and publications known to the authors. Results: Many studies examining urban/rural differences in the rate of high prevalence disorders have been reported. Most use a ‘one size fits all’ definition of urban and rural, which assumes location is the key issue. The majority fail to show the purported difference in prevalence between the two settings. In general, studies have not examined interaction effects, but have simply treated the independent variables as main effects. Available data suggest that a variety of socio-demographic factors are more powerful predictors of difference in prevalence than is the location of residence. Conclusion: Further studies are required to understand if and how rural or urban place contributes to the development of psychiatric morbidity. These studies should mirror the clinical situation by taking into account a variety of individual and community-based (including urban/rural place) risk factors which may be important determinants of mental health and mental illness, and examining the interaction between them. This may then identify the nature of any differences or what issues are specific to, or especially important, in the rural setting.
Algorithms for Automatic Transistor Sizing in CMOS Digital Circuits

This paper describes the algorithms for automatic transistor sizing (determination of device width and length) of CMOS digital circuits. In CMOS circuits, since power dissipation is small and not a limiting factor, the sizing algorithm is geared toward minimizing area. The program XTRAS (Xerox TRAnsistor Sizing Program) which determines transistor sizes as well as calculates path delays is described. Equations for the calculation of gate area, node capacitances, and rise and fall delays are given. Example circuits sized using XTRAS are compared and found to be within 10% of SPICE circuit simulations.
A 14-bit 200MS/s current-steering DAC achieving over 82dB SFDR with digitally-assisted calibration and dynamic matching techniques

This paper presents a digitally-assisted two-step linearity enhancement technique for a 14-bit current-steering digital-to-analog converter. The static nonlinearity introduced by the wittingly small current sources for the sake of area reduction is firstly calibrated by evaluating and compensating the offset current between the average of 6-bit MSB array and the sum of 8-bit LSB array. An unique dynamic element matching (DEM) algorithm is then applied to suppress the residual nonlinearities without introducing too many transient glitches at the output. A 14-bit 200MS/s DAC is fabricated to verify the proposed scheme and successfully demonstrates a decent linearity of 82.5dB SFDR within an area of 0.45mm2 in a 0.18-μm CMOS process. A good power efficiency is kept at the same time as well.
Neuronal Culture Microenvironments Determine Preferences in Bioenergetic Pathway Use

In the brain, metabolic supply and demand is directly coupled to neuronal activation. Methods for culturing primary rodent brain cells have come of age and are geared toward sophisticated modeling of human brain physiology and pathology. However, the impact of the culture microenvironment on neuronal function is rarely considered. Therefore, we investigated the role of different neuronal culture supplements for neuronal survival and metabolic activity in a model of metabolic deprivation of neurons using oxygen deprivation, glucose deprivation, as well as live cell metabolic flux analysis. We demonstrate the impact of neuronal culture conditions on metabolic function and neuronal survival under conditions of metabolic stress. In particular, we find that the common neuronal cell culture supplement B27 protects neurons from cell death under hypoxic conditions and inhibits glycolysis. Furthermore, we present data that B27 as well as the alternative neuronal culture supplement N2 restrict neuronal glucose metabolism. On the contrary, we find that the more modern supplement GS21 promotes neuronal energy metabolism. Our data support the notion that careful control of the metabolic environment is an essential component in modeling brain function and the cellular and molecular pathophysiology of brain disease in culture.
Numerical modeling of pseudotachylyte injection vein formation by Will Sawyer Class of 2016

Pseudotachylyte, a fault rock formed through coseismic frictional melting, provides an important record of coseismic mechanics. In particular, injection veins formed at a high angle to the fault surface have been used to estimate rupture directivity, velocity, pulse length, stress and strength drop, as well as slip weakening distance and wall rock sti ness. These studies, however, have generally treated injection vein formation as a purely elastic process and have assumed that processes of melt generation, transport, and solidi cation have little in uence on the nal vein geometry. Using a modi ed analytical approximation of injection vein formation based on a dike intrusion model we nd that the timescales of quenching and ow propagation are similar for a suite injection veins in the Fort Foster Brittle Zone, indicating a complex, dynamic process whose behavior is not fully captured by the current approach. To assess the applicability of the simplifying assumptions of the dike model when applied to injection veins we employ a nite-element time-dependent model of injection vein formation. This model couples elastic deformation of the wall rock with the uid dynamics and heat transfer of the frictional melt. The nal geometry of a majority of injection veins is una ected by the inclusion of these processes. However, some injection veins are ow limited, with a nal geometry re ecting cooling of the vein before it reaches an elastic equilibrium with the wall rock. In these cases, numerical results are signi cantly di erent from the dike model, and two basic assumptions of the dike model, self-similar growth and a uniform pressure gradient, are shown to be false. Additionally, we provide two new constrains on the Fort Foster coseismic environment: a lower limit on the initial melt temperature of 1400 ◦C, and either signi cant coseismic wall rock softening or high transient tensile stress.
Emerging model systems in evo‐devo: horned beetles and the origins of diversity

SUMMARY Horned beetles and beetle horns are emerging as a model system suited to address fundamental questions in evolutionary developmental biology. Here we briefly review the biology of horned beetles and highlight the unusual opportunities they provide for evo‐devo research. We then summarize recent advances in the development of new approaches and techniques that are now available to scientists interested in working with these organisms. We end by discussing ways to implement and combine these new approaches to explore new frontiers in evo‐devo research previously unavailable to reseachers working outside traditional model organisms.
Constraints on the CO content of Callisto’s exosphere based on ALMA archival data

Callisto is the second largest moon of Jupiter and the third largest in the Solar System and in a wide enough orbit to avoid Jupiter’s harmful magnetosphere. It is tidally locked in its orbit so that the same side of Callisto always looks at Jupiter. Water (H2O) detections from the two leading and trailing hemispheres of Callisto are somewhat different which might be an indication of asymmetry in its atmosphere. A theoretical atmosphere density model of Callisto predicts that if the atmosphere of Callisto has been formed in oxidizing state, the top constituents of sublimation profile density are expected to be H2O, CO and CO2. Callisto’s tenuous CO2 atmosphere have been observed directly by the Galileo Near Infrared Mapping Spectrometer. Likewise, water absorption lines are detected from the leading hemisphere of Callisto. These findings and lack of information about CO, motivated us to search for CO lines in Callisto’s atmosphere. ESA’s (European Space Agency) JUICE spacecraft in 2030 will investigate Callisto’s exosphere in more detail. To prepare for that investigation it might be possible to use ground-based data from Atacama Large Millimeter Array (ALMA) in Chile to detect carbon monoxide (CO) lines. All available observations covering the COJ=2−1 transition frequency toward Callisto are extracted from ALMA archive. Then, to find the best fitted visibilities, the extracted data are analysed using a circular disc model for Callisto and spectra are extracted directly from the interferometric visibilities. Afterwards, averaging of the fitted spectra are performed for both leading and trailing hemispheres. Since the average spectra does not show any emission or absorption CO line, upper column density of CO by using rms noise level is calculated which gives  2 × 1015 cm−2. The result shows that, CO is likely not the most dominant species in Callisto’s atmosphere. For comparison, COJ=2−1 spectra towards Saturn’s moon Titan, are also extracted from the ALMA archive. The detected lines are strong and broad and CO column density is estimated to be at least five to six orders of magnitude higher in the atmosphere of Titan, than in that of Callisto.
Adult Ciliary Epithelial Cells, Previously Identified as Retinal Stem Cells with Potential for Retinal Repair, Fail to Differentiate into New Rod Photoreceptors

The ciliary margin in lower vertebrates is a site of continual retinal neurogenesis and a stem cell niche. By contrast, the human eye ceases retinal neuron production before birth and loss of photoreceptors during life is permanent and a major cause of blindness. The discovery of a proliferative cell population in the ciliary epithelium (CE) of the adult mammalian eye, designated retinal stem cells, raised the possibility that these cells could help to restore sight by replacing lost photoreceptors. We previously demonstrated the feasibility of photoreceptor transplantation using cells from the developing retina. CE cells could provide a renewable source of photoreceptors for transplantation. Several laboratories reported that these cells generate new photoreceptors, whereas a recent report questioned the existence of retinal stem cells. We used Nrl.gfp transgenic mice that express green fluorescent protein in rod photoreceptors to assess definitively the ability of CE cells to generate new photoreceptors. We report that CE cells expanded in monolayer cultures, lose pigmentation, and express a subset of eye field and retinal progenitor cell markers. Simultaneously, they continue to express some markers characteristic of differentiated CE and typically lack a neuronal morphology. Previously reported photoreceptor differentiation conditions used for CE cells, as well as conditions used to differentiate embryonic retinal progenitor cells (RPCs) and embryonic stem cell‐derived RPCs, do not effectively activate the Nrl‐regulated photoreceptor differentiation program. Therefore, we conclude that CE cells lack potential for photoreceptor differentiation and would require reprogramming to be useful as a source of new photoreceptors. STEM Cells 2010;28:1048–1059
Overexpression of DnWRKY11 enhanced salt and drought stress tolerance of transgenic tobacco

Dendrobium seedlings showed low survival rate when they were transferred from in vitro conditions to greenhouse or field environment. One of the major reasons is their low tolerance to environmental changes. WRKY transcription factors are one of the largest families of transcriptional regulators in plants. They are involved in various biotic and abiotic stress responses. One DnWRKY11 gene was isolated from Dendrobium nobile. To explore the function of DnWRKY11 in Dendrobium defense responses to abiotic stress, it was overexpressed in tobacco. Under salt and drought stresses, the DnWRKY11 transgenic tobacco showed higher germination rate, longer root length, higher fresh weight, higher activities of catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and lower content of malonidialdehyde (MDA) than the wild type. These results proved the important roles of DnWRKY11 in plant response to drought and salt stresses, and provided a potential gene for improving environmental stress tolerance of Dendrobium seedlings.