Miracle-dz/UniFAR-FTUs huggingface dataset:
Correction for eddy current induced Bo shifts in diffusion‐weighted echo‐planar imaging

The importance of diffusion‐weighted MRI in the assessment of acute stroke is well‐recognized, and quantitative maps of the apparent diffusion coefficient (ADC) are now widely used. Echo‐planar imaging provides a robust method of acquiring diffusion‐weighted images free of motion artifact. However, initial experience with clinical MRI systems indicates that calculation of artifact‐free ADC maps from a series of echo‐planar diffusion‐weighted images is not necessarily straight‐forward. One of the problems is that frequency shifts resulting from eddy currents can cause misregistration of base diffusion‐weighted images. In this study, an on‐line correction method that overcomes this problem is described, and phantom and human images that demonstrate the validity of the technique are presented. The method uses a non‐phase‐encoded reference scan to correct the phase of each echo in the echo train, and can provide ADC maps that are free of misregistration artifacts, without the need for off‐line postprocessing. Magn Reson Med 41:95‐102, 1999. © 1999 Wiley‐Liss, Inc.
The cultural requirements of Endamoeba coli and the comparative effects of drying on the cysts of E coli and E histolytica.

Summary 1. A modification of the zinc sulfate centrifugal flotation technique is described for concentrating cysts of E. coli and E. histolytica from stools and cultures in watch glasses with minimum amounts of foreign material. 2. Several strains of E. coli have been cultivated from cysts that were freed by microisolation from bacteria and transferred into riced whole egg medium that was seeded with organism t and B. subtilis. 3. Encystation of E. coli in vitro was obtained by the method of Dobell in cultures with an undetermined number of species of bacteria and also with only three species, organism t, B. subtilis and Streptococcus zymogenes. 4. On the basis of culturability and microscopic appearance the cysts of E. coli were not demonstrably affected by drying; cysts of E. histolytica were irreversibly damaged by drying.
Severe life stress as a predictor of early disease progression in HIV infection.

OBJECTIVE Although there is evidence that stress is associated with alterations in immunity, the role of emotional factors in the onset and course of immune-based diseases such as cancer and AIDS has not been established. This prospective study was designed to test the hypothesis that stressful life events accelerate the course of HIV disease. METHOD Ninety-three HIV-positive homosexual men who were without clinical symptoms at the time of entry into the study were studied for up to 42 months. Subjects received comprehensive medical, neurological, neuropsychological, and psychiatric assessments every 6 months, including assessment of stressful life events during the preceding 6-month interval. Several statistical approaches were used to assess the relation between stress and disease progression. RESULTS The time of the first disease progression was analyzed with a proportional hazard survival method, which demonstrated that the more severe the life stress experienced, the greater the risk of early HIV disease progression. Specifically, for every one severe stress per 6-month study interval, the risk of early disease progression was doubled. Among a subset of 66 subjects who had been in the study for at least 24 months, logistic regression analyses showed that higher severe life stress increased the odds of developing HIV disease progression nearly fourfold. the degree of disease progression was also predicted by severe life stress when a proportional odds logistic regression model was used for analysis. CONCLUSIONS This report presents the first evidence from a prospective research study that severe life event stress is associated with an increased rate of early HIV disease progression.
Acceptability and feasibility of a virtual intervention to help people living with HIV manage their daily therapies

We conducted a study of the acceptability and feasibility of a web application which was designed to empower people living with HIV to manage their daily antiretroviral therapies. The application (VIH-TAVIE) consists of four interactive computer sessions with a virtual nurse who guides the user through a learning process aimed at enhancing treatment management capacities. The information furnished and the strategies proposed by the nurse are tailored, based on the responses provided by the user. The application was evaluated in a hospital setting as an adjunct to usual care. The participants (n = 71) had a mean age of 47 years (SD = 7.6). There were 59 men and 12 women. They had been diagnosed with HIV some 15 years earlier and had been on antiretroviral medication for a mean duration of 11 years. Data were collected by acceptability questionnaires, field notes and observations. Most participants found the application easy to use. They learned tips for taking their medication, diminishing adverse side-effects and maintaining a positive attitude towards treatment. Many participants deemed their experience with the application highly satisfactory and felt that it met their needs with respect to strategies and proficiencies despite their long experience of medication use. The results of the study support the feasibility and acceptability of the intervention.
Does Weight Gain during Pregnancy Influence Postpartum Depression?

The goal of this study was to determine if weight gain during pregnancy has an effect on postpartum depression (PPD). Data were collected in a web survey from 238 women who had recently given birth. The data were analyzed for the total sample and also by body weight category before pregnancy. Findings revealed that weight gain was inversely associated with PPD for the obese women in our sample. For these women, the less weight they gained, the more likely they were to experience PPD. History of depression, partner support, and age were also predictors of PPD.
Rietveld refinement of langbeinite-type K2YHf(PO4)3

Potassium yttrium hafnium tris(orthophosphate) belongs to the langbeinite-family and is built up from [MO6] octahedra [in which the positions of the two independent M sites are mutually occupied by Y and Hf in a 0.605 (10):0.395 (10) ratio] and [PO4] tetrahedra connected via vertices into a three-dimensional framework. This framework is penetrated by large closed cavities in which the two independent K atoms are located; one of the K atoms is nine-coordinated and the other is 12-coordinated by surrounding O atoms. The K, Y and Hf atoms lie on threefold rotation axes, whereas the P and O atoms are located in general positions.
Prevalence of antibodies to hepatitis C virus among patients with leprosy in several African countries and the Yemen

The prevalence of anti‐HCV was determined in 1,309 leprosy patients and a control group of 1,469 subjects from 6 sub‐Saharan African countries and the Yemen. Sera found positive by an initial second generation ELISA were subjected to 3 additional confirmatory tests. The anti‐HCV prevalence in leprosy patients (7.1%) was significantly higher than in the control group (2.6%). HCV seroprevalence increased with age in both the control and leprosy groups. No statistically significant difference could be found between anti‐HCV prevalence and the several clinical forms of leprosy among patients. The results of this study indicate a high degree of exposure or chronic carriage of hepatitis C among leprosy patients. © 1994 Wiley‐Liss, Inc.
A unified, scalable dual-field Montgomery multiplier architecture for ECCs

This paper proposes a unified, scalable dual-field Montgomery multiplier architecture which can operate in both prime GF(p) and binary extension fields GF(2n) for arbitrary prime numbers and irreducible polynomials. The Montgomery multiplier architecture has advantages in speed and flexibility for operator size compared with conventional architectures using long adders or long-bit × short-bit multipliers by introducing using a balanced r-bit×r-bit dual field multiplier. Finally, the hardware size of multipliers on GF(2n) for various r, are investigated. The Montgomery multiplier provides efficient execution of Montgomery multiplication in either field for different operand lengths, which suitable be applied to elliptic curve cryptographic (ECC) processors.
Efficiency of the RDVFS countermeasure

The use of Dynamic Voltage and Frequency Scaling technique (DVFS) in Systems-on-Chip is becoming more and more common. This technique, re-named RDVFS for the occasion, has recently been proposed as a countermeasure against Side Channel Attacks (SCA) through the randomization of the choices of V and F, at the expense of power consumption. In this paper, theoretical and practical assessments of the robustness against Correlation Power Analysis (CPA) of the RDVFS countermeasure is proposed.
Investor sentiment, variance risk premium and delta-hedged gains

ABSTRACT Delta-hedged gains are supposed to be negative and represent a volatility risk premium. Using a sample of Standard & Poor 500 index options from 2006 to 2009, this study documents two anomalies that cannot be explained by the volatility risk premium. First, delta-hedged gains are more negative for out-of-money options than for at-the-money options. Second, delta-hedged gains are significantly positive during financial crisis period. We propose a behavioural explanation in which both option prices and stock prices are affected by investor’s sentiment, but pessimistic sentiment has a greater impact on stock market than option market. This asymmetric response to pessimistic mood in turn affects the relative expensiveness of option prices.
The Value of Mutual Fund Rankings to the Individual Investor

This paper investigates whether an investment strategy based on mutual fund rankings by the popular press can earn abnormal returns. In an efficient market, mutual fund managers cannot beat the market and any superior performance is simply luck and does not persist. The sample contains 757 funds that have received rankings from Barron's, Business Week, and Forbes between 1993-1995. Using published rankings as the sample selection criterion has several advantages. First, these funds do not suffer from survivorship bias. Second, the sample was chosen without analyzing prior period data. Therefore, the evaluation period and methodology are independent of the selection period and methodology. Third, the funds examined in this paper are chosen from all funds available as of the publication dates. Therefore, the rankings represent an investment strategy that can be easily implemented by investors. Lastly, the three publications used in this study have a large readership and many investors will be interested in the findings. This study shows that an investment strategy based on popular mutual fund rankings did not produce superior performance. The ranked funds have higher excess returns relative to peer funds during the pre-ranking period, but have similar excess returns as their peers in the post-ranking period. These results do not support the short-term persistent performance hypothesis. The ranked funds also have higher risk, measured by standard deviations, in both the pre- and post-ranking periods. The majority of the ranked funds (54%) have negative risk-adjusted performance in the post-ranking period against a 4-factor benchmark and 65% of the funds have lower performance compared to the pre-ranking period. The results are not consistent with persistent risk-adjusted performance.
Cell aggregation precedes the onset of Sox9-expressing preSertoli cells in the genital ridge of mouse

Sox9 is expressed at the onset of the genital ridge formation in both sexes. It is assumed that Sry, the testis determining gene, turns Sox9 on in male embryos because it is turned off in female embryos. Spatial expression of Sry follows a cranio-caudal pattern. Here, we asked if Sox9 is expressed in the same cell lineage and with a similar pattern as Sry. A correlative study between the structural changes in the genital ridge and the immunocytochemical localization of Sox9-positive cells was undertaken. We used a transgenic strain expressing the green fluorescent protein (GFP) that considerably enhanced the cell context where the first Sox9-positive cells appear. Although Sox9-positive cells are located among loose mesenchymal cells by stages of 8–14 tail somites (ts) in both sexes, they are absent in the thickening coelomic epithelium of females. At 15 ts the first Sox9-positive cells appear within the core of the condensed cells only in male genital ridges. At 17 ts, a gradient of Sox9-positive cells in males is apparent, closely following the cranio-caudal pattern of cell aggregation seen in genital ridges of both sexes. Hence, our results suggest that Sox9 is expressed only in loose mesenchymal cells in both sexes and that expression of Sox9 in males requires the prior aggregation of cells in the genital ridges. The correspondence of Sox9 and Sry pattern of expression supports that both genes are expressed in the preSertoli cell lineage in the core of the genital ridges.
Genome-Wide Mapping of Targets of Maize Histone Deacetylase HDA101 Reveals Its Function and Regulatory Mechanism during Seed Development[OPEN]

Maize histone deacetylase HDA101 mainly targets active genes regulating H4K5 acetylation and represses a small subset of targets whose expression must be kept at a low level during seed development. Histone deacetylases (HDACs) regulate histone acetylation levels by removing the acetyl group from lysine residues. The maize (Zea mays) HDAC HDA101 influences several aspects of development, including kernel size; however, the molecular mechanism by which HDA101 affects kernel development remains unknown. In this study, we find that HDA101 regulates the expression of transfer cell-specific genes, suggesting that their misregulation may be associated with the defects in differentiation of endosperm transfer cells and smaller kernels observed in hda101 mutants. To investigate HDA101 function during the early stages of seed development, we performed genome-wide mapping of HDA101 binding sites. We observed that, like mammalian HDACs, HDA101 mainly targets highly and intermediately expressed genes. Although loss of HDA101 can induce histone hyperacetylation of its direct targets, this often does not involve variation in transcript levels. A small subset of inactive genes that must be negatively regulated during kernel development is also targeted by HDA101 and its loss leads to hyperacetylation and increased expression of these inactive genes. Finally, we report that HDA101 interacts with members of different chromatin remodeling complexes, such as NFC103/MSI1 and SNL1/SIN3-like protein corepressors. Taken together, our results reveal a complex genetic network regulated by HDA101 during seed development and provide insight into the different mechanisms of HDA101-mediated regulation of transcriptionally active and inactive genes.
Do teacher opinion leaders impact other teachers

DO TEACHER OPINION LEADERS IMPACT OTHER TEACHERS Annette Eyman, MA University of Nebraska, 2001 Advisor: Dr. Shereen Bingham The purpose of this study was to determine if there were identified opinion leaders among teachers and how those opinion leaders may have influenced teachers’ acceptance levels of the standards and assessment implementation for the language arts curriculum. Three phases of research were conducted. Twenty-four secondary language arts teachers and 109 elementary classroom teachers in the Papillion-LaVista School District were first surveyed to determine their level of acceptance of the standards and assessments for language arts. Each of the respondents was then asked to identify the opinion leaders, or those they turn to and trust regarding the standards and assessment implementation. The identified opinion leaders were then asked to participate in focus groups where they were asked to share their sources of information and views regarding the standards and assessment process. A total of 32 teachers were identified as opinion leaders. The list of identified opinion leaders was compared to the list of teachers who served on the core team that was responsible for writing, and disseminating information regarding the standards and assessments. The acceptance levels of those four schools that had opinion leaders on the core team were compared to the acceptance levels of those schools without opinion leaders on the core team. There were three elementary schools and one secondary school. It was discovered that elementary schools that had teachers on the core team had a higher level of acceptance than the other elementary schools that did not have opinion leaders on the core team. This was not found to be true for the secondary schools. The findings also indicate that overall elementary and secondary teachers are neutral regarding their acceptance levels of the standards and assessment process. The elementary opinion leader teachers were more positive about the process citing the direct correlation between the assessments and the curriculum as the main strength. The secondary opinion leader teachers were not as positive, citing the fact that the assessments were not taken from the curriculum as a weakness. Additional findings indicate that the media and general talk in the education community were the first sources of information and being involved, for those that were, was the most influential as the opinion leaders determined their level of acceptance
Detecting Parallel Browsing to Improve Web Predictive Modeling

Present-day web browsers possess several features that facilitate browsing tasks. Among these features, one of the most useful is the possibility of using tabs. Nowadays, it is very common for web users to use several tabs and to switch from one to another while navigating. Taking into account parallel browsing is thus becoming very important in the frame of web usage mining. Although many studies about web users' navigational behavior have been conducted, few of these studies deal with parallel browsing. This paper is dedicated to such a study. Taking into account parallel browsing involves to have some information about when tab switches are performed in user sessions. However, navigation logs usually do not contain such informations and parallel sessions appear in a mixed fashion. Therefore, we propose to get this information in an implicit way. We thus propose the TABAKO model, which is able to detect tab switches in raw navigation logs and to benefit from such a knowledge in order to improve the quality of web recommendations.
Multiple sites in HIV-1 reverse transcriptase associated with virological response to combination therapy

ObjectiveTo determine whether analysis of sequence variation in reverse transcriptase at baseline can explain differences in response to combination antiretroviral therapy. MethodsAmino acid sequences of reverse transcriptase obtained from baseline isolates from 55 patients included in a trial of zidovudine and didanosine versus zidovudine/didanosine/nevirapine (ACTG241) were analysed. Simple and multiple linear regression were used to determine the relationship between numbers and identity of mutations at baseline and virological response after 8 and 48 weeks. ResultsNumbers of baseline zidovudine resistance mutations were predictive of short-term response (week 8). Amino acid identity at position 215 explained > 20% of the variation in response at week 8, but less at week 48. Multiple regression identified the combinations: 215 + 44 and 41 + 202, each of which explained about 30% of the variation in week 8 response. A model incorporating amino acids 214 + 215 + 60 + 202 + baseline viral load explained > 40% of the variation in response at week 48. Unexpectedly, the mutant combination 60I + 215Y/F responded threefold better than 60V + 215Y/F over 48 weeks. ConclusionsUse of clinical data to analyse virological response to combination therapy has revealed effects of baseline amino acid mutations at sites not previously identified as being important in antiretroviral resistance. Predictors of long-term responses were different from those involved in the short term and may require more complex analysis.
Fertility drugs and ovarian cancer risk: a critical review of the literature

There is evidence that medications used for ovarian stimulation and in vitro fertilization may be associated with ovarian cancer. In this review, we attempt to describe this relationship according to the most recent epidemiologic data and to present the possible mechanisms on the molecular level that could potentially explain this correlation. Currently there is no proven relationship between any type of ovarian cancer and drugs used for infertility treatment. Overall, infertile women have increased risk for ovarian malignancies. Nulligravidas that received treatment are at increased risk for ovarian malignancy as compared to women that conceived after treatment. More studies with the appropriate statistical power and follow‐up time, as well as with better adjustment for confounding factors, which coexist in infertile patients, are required to evaluate accurately the long‐term effects of these drugs and procedures.
Cloning and surface expression in Escherichia coli of a structural gene encoding a surface protein of Haemophilus influenzae type b

Recombinant DNA technology was used to clone a gene coding for a surface protein of Haemophilus influenzae type b (Hib) into Escherichia coli. Chromosomal DNA from a clinical isolate of Hib was cleaved with EcoRI and ligated into plasmid vectors containing three different translational reading frames. E. coli carrying recombinant plasmids were screened in a colony blot-radioimmunoassay system by using murine monoclonal antibodies (mabs) directed against cell surface-exposed proteins of Hib. mab 7B2, which is specific for a Hib surface protein with an apparent molecular weight of 27,000 (27K), reacted with several recombinant strains of E. coli. Restriction analysis revealed the presence of a 9.1-kilobase DNA insert in each of these recombinant plasmids and also determined that both transcription and translation of the Hib gene(s) coding for the 7B2-reactive antigen were not dependent on the lac operator and promoter of the vectors. Radioimmunoprecipitation and Western blot analyses showed that the antigenic determinant recognized by mab 7B2 in these recombinant E. coli was present in a 27K protein. In addition, this 27K protein was shown to be both localized on the surface of these E. coli cells and accessible to antibody.
A relative navigation sensor for CubeSats based on retro-reflective markers

Over the last years, nanosatellites based on the CubeSat standard have been increasingly exploited by both academic institutions and commercial companies. The low cost and short development time of CubeSats make such miniature spacecraft interesting for a variety of applications. A particularly appealing future field of application for nanosatellites is On-Orbit Servicing of existing orbital assets. A number of mission concepts foresee the employment of miniature spacecraft to perform a variety of operations on orbital vehicles, ranging from inspection and monitoring to assembly and repairing. In this framework, the development of technologies that enable proximity navigation and/or docking between a nanosatellite chaser and a target object is of interest. In particular, miniaturized navigation sensors for the estimation of relative position and attitude of the involved vehicles are required. The work presented here focuses on the development of an IR-based relative navigation sensor compatible with CubeSat standard nanosatellites. The system estimates the relative pose and position of the target by taking images of the object, which is equipped with retro-reflecting fiducial markers illuminated by an array of IR LEDs on the chaser. The system architecture and operation are described, and preliminary laboratory test results are presented.