Miracle-dz/UniFAR-FTUs huggingface dataset:
B-DNA twisting correlates with base-pair morphology.

The observed sequence dependence of the mean twist angles in 38 B-DNA crystal structures can be understood in terms of simple geometrical features of the constituent base-pairs. Structures with low twist appear to unwind in response to severe steric clashes of large exocyclic groups (such as NH2-NH2) in the major and minor grooves, while those with high twist are subjected to lesser contacts (H-O and H-H). We offer a simple clash function that depends on base-pair morphology (i.e. the chemical constitution of base-pairs) and satisfactorily accounts for the twist angles of the ten common Watson-Crick dimer steps both in the solid state and in solution. The twist-clash correlation that we find here still holds when extended to modified bases. In addition to Calladine's purine-purine clashes, we add other close contacts between bases in the grooves, and consider the conformational restrictions on the geometry of the sugar-phosphate backbone (namely, we emphasize the tendency of DNA to conserve virtual backbone length). The significance of this finding is threefold: (1) sequence-dependent DNA twisting is directly involved in protein-DNA interactions; (2) strong correlation between Twist and Roll helps to elucidate the bending of the double helix as a function of base sequence; (3) it is possible to anticipate the effects of chemical modifications on twisting and bending. The mutual correlations of other structural parameters with the twist make this angle a primary determinant of DNA conformational heterogeneity.
Dynamic learner profiling and automatic learner classification for adaptive e-learning environment

E-learning allows learners individually to learn “anywhere, anytime” and offers immediate access to specific information. However, learners have different behaviors, learning styles, attitudes, and aptitudes, which affect their learning process, and therefore learning environments need to adapt according to these differences, so as to increase the results of the learning process. In addition, providing the same learning content to all the learners may lead to a reduction in the learner's performance. Hence, there is a need to classify the learners based on their performance and knowledge level. Learner profiles play an important role in making the e-learning environment adaptive. Providing an adaptive learning environment, catering to the changing needs and behavior of the learner can be achieved by evolving dynamic learner profiles. Navigation logs can be used to analyze learners’ behavior over a period of time. In this work, we propose dynamic learner profiling to cater to changing learner behaviors, styles, goals, preferences, performances, knowledge level, learner's state, content difficulty, and feedbacks. Based on the continuous observation of learner preferences and requirements, the learner profile is dynamically updated. Furthermore, we propose an automatic learner classification to construct the learner profile and identify the complexity level of learning content, using the Bayesian belief network and decision tree techniques. We evaluated our system with two traditional adaptive e-learning systems, using static profiles and behavioral aspects, through our performance evaluation method of different learner types. In addition, we compared the actual learners’ data with the system generated results for various types of learners, and showed the increased interest in their learning outcomes.
Evidence that age‐related changes in p38 MAP kinase contribute to the decreased steroid production by the adrenocortical cells from old rats

The current studies were initiated to investigate whether excessive oxidative stress exerts its antisteroidogenic action through modulation of oxidant‐sensitive mitogen‐activated protein kinase (MAPK) signaling pathways. Western blot analysis indicated that aging caused increased phosphorylation and activation of rat adrenal p38 MAPK, but not the ERK1/2 or JNK1/2. Lipid peroxidation measurements (an index of cellular oxidative stress) indicated that adrenal membranes from young animals contained only minimal levels of endogenous thiobarbituric acid‐reactive substances (TBARS), and exposure of membranes to enzymatic and non‐enzymatic pro‐oxidants enhanced TBARS formation approximately 12‐ and 20‐fold, respectively. The adrenal membranes from old animals showed much more susceptibility to lipid peroxidation and exhibited roughly 4‐ to 6‐fold higher TBARS formation than young controls both under basal conditions and in response to pro‐oxidants. Qualitatively similar results were obtained when lipid peroxide formation was measured using a sensitive FOXRS (ferrous oxidation‐xylenol orange‐reactive substances) technique. We next tested whether aging‐induced excessive oxidative insult alters steroidogenesis through modulation of MAPK signaling pathway. Treatment of adrenocortical cells from old rats with specific p38 MAPK inhibitors restored Bt2cAMP‐stimulated steroidogenesis ~60–70% of the value seen in cells of young animals. Likewise, pretreatment of cells with reactive oxygen species (ROS) scavengers MnTMPyP and N‐acetyl cysteine also partially rescued age‐induced loss of steroid production. In contrast, simultaneous treatment of cells with ROS scavengers and p38 MAPK inhibitor did not produce any additional effect suggesting that both types of inhibitors exert their stimulatory action through inhibition of p38 MAPK activation. Collectively, these results indicate that p38 MAPK functions as a signaling effector in oxidative stress‐induced inhibition of steroidogenesis during aging.
Information and socioeconomic factors associated with early breastfeeding practices in rural and urban Morogoro, Tanzania

A cross‐sectional study was undertaken in a rural and an urban area in Tanzania with the aim of identifying factors related to early infant feeding practices. The study included 320 mothers from each area with infants below 7 mo of age. A significant proportion of both rural and urban mothers had erroneous beliefs about infant feeding practices. None of the socioeconomic, demographic or biological variables studied were associated with feeding practices. Urban residence was positively associated with the duration of exclusive but not predominant breastfeeding. Better knowledge about specific breastfeeding issues was positively associated with the duration of both exclusive and predominant breastfeeding. Ownership of a radio was positively associated with both exclusive and predominant breastfeeding in the rural area. Although both rural and urban mothers had a high antenatal clinic attendance rate, 65% of the rural and 14% of the urban mothers delivered at home. Urban mothers informed about breastfeeding at the antenatal clinic had better feeding practices.
In vitro comparison of the vitamin D endocrine system in 1,25(OH)2D3-responsive and –Resistant melanoma cells

We studied effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], its analog seocalcitol (EB 1089), and 25-hydroxyvitamin D3 [25(OH)D3], on the growth of seven melanoma cell lines. While three cell lines (MeWo, SK-Mel-28, SM) responded to antiproliferative effects of active vitamin D analogs, the others (SK-Mel-5, SK-Mel-25, IGR, MelJuso) were resistant. A strong induction (7000-fold) of 1,25-dihydroxyvitamin D-24-hydroxylase (24OHase, CYP24) mRNA was detected in responsive cell lines along with 1,25(OH)2D3-treatment, indicating functional integrity of vitamin D receptor (VDR)-mediated transcription. In contrast, induction of 24OHase was much lower in resistant melanoma cells (70-fold). VDR mRNA was induced up to 3–fold both in responsive and resistant cell lines along with 1,25(OH)2D3-treatment. RNA for vitamin D-activating enzymes vitamin D-25-hydroxylase (25OHase, CYP27A1) and 25-hydroxyvitamin D-1α-hydroxylase (1αOHase, CYP27B1) was detected in all melanoma cell lines analyzed, additionally we show splicing variants of 1αOHase in SK-Mel-28 cells. Expression of 25OHase and 1αOHase was marginally modulated along with treatment. Proliferation of melanoma cells was not inhibited by treatment with 25(OH)D3, indicating no significant stimulation of endogeneous production of antiproliferative acting 1,25(OH)2D3. In conclusion, we characterize the vitamin D endocrine system in melanoma cells and demonstrate that the majority of melanoma cell lines analyzed is resistant to antiproliferative effects of 1,25(OH)2D3. It can be speculated that these alterations are of importance for pathogenesis and growth of metastasizing malignant melanoma. Additionally, our findings indicate that only a minority of cases with metastasizing melanoma may represent a promising target for palliative treatment with new vitamin D analogs that exert little calcemic side effects or for pharmacological modulation of 1,25(OH)2D3-synthesis/metabolism.
Canine inherited ataxia

A previously unrecognized canine disorder consists of familial cortical cerebellar degeneration with many characteristics that are similar to inherited ataxias in humans. The disease occurs in Gordon setters and appears to be inherited as an autosomal recessive trait. The dogs appear normal during the first 6 months of life, but betwen 6 and 12 months of age they develop a broad‐based gait and dysmetria, followed by truncal ataxia. Nystagmus occurs late. The disorder is slowly and insidiously progressive. Neuropathological examination shows atrophy of the cerebellar cortex, particularly the pars in termedia. There is loss of Purkinje and granule cells, more severe in older dogs. Other parts of the neuraxis appear normal. These pathological changes resemble those of the familial human cerebellar cortical atrophies.
DIAGNÓSTICO FÍSICO CONSERVACIONISTA E DEGRADAÇÃO AMBIENTAL NO MUNICÍPIO DE CABACEIRAS - PB

O semiarido brasileiro apresenta um quadro biotico e abiotico ainda pouco conhecido cientificamente, o que acaba favorecendo a ocorrencia de degradacao ambiental, caracteristica marcante no conjunto de paisagens existentes, particularmente em suas zonas de maior secura climatica. Esse trabalho foi realizado no municipio de Cabaceiras-PB, conhecido como o de menor pluviosidade do Brasil, onde tambem existem serios impactos ambientais devido a ocorrencia de alguns processos naturais e principalmente atraves do uso e ocupacao da terra por atividades agropecuarias e extrativistas, desde o inicio do processo de ocupacao de seu territorio. O objetivo geral da pesquisa foi analisar o nivel de degradacao ambiental existente no municipio, tendo por objetivos especificos, realizar o diagnostico fisico-geografico, analisar a vulnerabilidade das unidades de paisagem associadas as atividades socioeconomicas e analisar a relacao do processo historico e socioeconomico de uso e ocupacao da terra com a degradacao ambiental. A metodologia foi fundamentada nas Teorias Geossistemica e Ecodinâmica, como tambem nos conceitos e processos causadores da degradacao ambiental. Para os procedimentos metodologicos, foram utilizadas tecnicas de geoprocessamento e sensoriamento remoto, acompanhadas de trabalhos de campo para validacao das respostas obtidas. Como resultados, concluiu-se que o municipio se encontra, predominantemente, em um estado de media vulnerabilidade, prevalecendo a morfogenese sobre a pedogenese e que 32,36% da area de estudo foi considerada como degradada, tendo em vista, principalmente, a perda de biomassa entre os periodos de 1989 e 2005. Do ponto de vista das acoes passiveis de conter a degradacao e melhorar a qualidade ambiental encontrada atualmente, buscou-se destacar algumas diretrizes e programas de intervencoes publicas existentes, as quais, sendo bem executadas, podem solucionar ou ao menos amenizar a situacao existente.
A validation study of the Hospital Anxiety and Depression Scale (HADS) in different groups of Dutch subjects

Background. Research on the dimensional structure and reliability of the Hospital Anxiety and Depression Scale (HADS) and its relationship with age is scarce. Moreover, its efficacy in determining the presence of depression in different patient groups has been questioned. Methods. Psychometric properties of the HADS were assessed in six different groups of Dutch subjects (N = 6165): (1) a random sample of younger adults (age 18–65 years) (N = 199); (2) a random sample of elderly subjects of 57 to 65 years of age (N = 1901); (3) a random sample of elderly subjects of 66 years or older (N = 3293); (4) a sample of consecutive general practice patients (N = 112); (5) a sample of consecutive general medical out-patients with unexplained somatic symptoms (N = 169); and (6) a sample of consecutive psychiatric out-patients (N = 491). Results. Evidence for a two-factor solution corresponding to the original two subscales of the HADS was found, although anxiety and depression subscales were strongly correlated. Homogeneity and test–retest reliability of the total scale and the subscales were good. The dimensional structure and reliability of the HADS was stable across medical settings and age groups. The correlations between HADS scores and age were small. The total HADS scale showed a better balance between sensitivity and positive predictive value (PPV) in identifying cases of psychiatric disorder as defined by the Present State Examination than the depression subscale in identifying cases of unipolar depression as defined by ICD-8. Conclusions. The moderate PPV suggests that the HADS is best used as a screening questionnaire and not as a ‘case-identifier’ for psychiatric disorder or depression.
Aflatoxin control and prevention strategies in key crops of Sub-Saharan Africa

Aflatoxins are secondary fungal metabolites that contaminate agricultural commodities and can cause sickness or death in humans and animals. Risk of aflatoxin contamination of food and feed in Africa is increased due to environmental, agronomic and socio-economic factors. Environmental conditions especially high humidity and temperature favour fungal proliferation, but also drought conditions increase risk of aflatoxin contamination. Low-input farming practices compound fungal and aflatoxin contamination of crops. The socio-economic and food security status of the majority of inhabitants of sub-Saharan Africa leaves them few options for choosing low-risk and high quality products. Several technologies have been tested in Africa to reduce aflatoxin risk. Field management practices that increase yields can reduce the risk of aflatoxin development. They include use of resistant varieties, crop rotation, well-timed planting, weed control, pest control especially control of insect pests and avoiding drought and nutritional stress through fertilization and irrigation. Measures to stop the infection process by controlling the aflatoxin causing fungi in the field are achieved through use of pesticides and atoxigenic fungi to competitively displace toxigenic fungi, and timely harvest. Post-harvest interventions that reduce aflatoxin include rapid and proper drying, proper transportation and packaging, sorting, cleaning, drying, smoking, post harvest insect control, and the use of botanicals or synthetic pesticides as storage protectants. Another approach is to reduce the frequent consumption of ‘high risk’ foods (especially maize and groundnut) by consuming a more varied diet, and diversifying the diet into less risky staples like sorghum and millet. Chemo-preventive measures that can reduce aflatoxin effect include daily consumption of chlorophyllin or oltipraz and incorporating hydrated sodium calcium alumino-silicates into the diet. Reduction and detoxification of aflatoxin is often achieved physically (sorting, physical segregation, flotation etc.), chemically (e.g. calcium hydroxide, ammonia) and microbiologically by incorporating pro-biotics or lactic acid bacteria into the diet. Millers can use blending of less and more contaminated products to reduce the overall risk. There is need for efficient monitoring and surveillance with cost-effective sampling and analytical methods to reduce risk in Africa. Public education and awareness can sensitize the population on aflatoxin risk and its management. Key words: Aflatoxin, Sub-Saharan Africa, control measures.
A Longitudinal Study of Respiratory Health of Toluene Diisocyanate Production Workers

A longitudinal comparison of 305 toluene diisocyanate (TDI) and 581 hydrocarbons workers employed at a Texas chemical manufacturing facility from 1971 through 1997 tested whether workplace exposure to TDI was associated with changes in any of the respiratory measures collected by the company’s health surveillance program. Mean TDI exposures measured 96.9 ppb-months, or 2.3 ppb per job. At the end of the study, there were no differences in self-reported symptoms between the groups. Longitudinal analyses of symptoms and pulmonary function showed no correlation with TDI exposure, yielding an average annual decrease in forced expiratory volume at 1 second of 30 mL per year. We concluded that exposure to TDI at workplace concentrations was not associated with respiratory illnesses in this cohort, and consistent with other recent research, it seemed not to accelerate the normal age-related decline in pulmonary function.
Intervention Strategies to Improve Students' Academic Performance in Public Secondary Schools in Arid and Semi-Arid Lands in Kenya

Fullan (2007) defined school as a community of active people where teachers in a classroom environment convey formal education to learners. A school therefore facilitates education. Schools, whether government aided or private sponsored, have stakeholders who undertake various activities. In light of this, studentsi¯ academic performance has been a key issue in education with many believing that the education programmes are not well interpreted in schools; thus resulting in poor academic performance. This has resulted into finger pointing among stake holders. However, the fact of the matter is that something should be done to improve the current situation. Kaggwa (2003) explained academic performance as the quality and quantity of knowledge, skills, techniques and positive attitudes, behaviors and philosophy that students achieve. The World Bank (2002) further observes that this achievement is evaluated by the mark or grade that student attain in tests or examinations done at the end of the topic, term or year or education cycle. Hence, the quality of the grades and the number of students that pass in various grades determine the level of academic performance. Academic performance is, therefore, a concern of people who have vested interest in schools. They may include parents, students, teachers, proprietors and the entire society that forms the school as a community. Unless all stakeholders are involved, school achievements including studentsi¯ performance may not be realized (Dervitsiotis, 2004). Every student has the potential to learn and become a responsible citizen if given a conducive environment. Therefore, it is worth mentioning that intervening at the earliest stages, can lead to studentsi¯ success. Intervention can be defined as the systematic and explicit instruction provided to accelerate growth in an area of identified need (Kaggwa, 2003). Interventions can be provided by both special and general teachers and they are designed to improve performance relative to a specific, measurable goal. Interventions are generally based on valid information about current performance, whereby realistic implementation and ongoing student progress monitoring are essential. Therefore, for any intervention to be effective, the programmes designed should be based on clearly defined objectives, and the program should be monitored and evaluated (Kaggwa, 2003). More particularly, studentsi¯ needs should be analyzed and programs should be designed to address these. Of more importance is that intervention strategies should not be implemented because they are popular or interesting. Rather, they should be able to address the needs of the students in their institution, given that schools operate in different contexts; hence, no one size fits all. Approaches will vary according to the school context. Student support programmes, behavior modification, life skills programmes, parental involvement and capacity building are some intervention strategies to enhance studentsi¯ performance (Kaggwa, 2003).
Testing for persistence in mutual fund performance and the ex-post verification problem: evidence from the Greek market

The present study examines a series of performance measures with the aim of solving the ex-post verification problem. These measures are employed to test the performance persistence hypothesis of domestic equity funds in Greece, during the period 1998–2004. Correctly adjusting for risk factors and documented portfolio strategies explains a significant part of the reported persistence. The intercept of the augmented Carhart regression is proposed as the most appropriate performance measure. Using this measure, weak evidence for persistence, only before 2001, is documented. The growth of the fund industry, the direction of flows to past winners and the integration in the international financial system are suggested to be the reasons for the absence of performance persistence.
Morphological analysis of cases with ectopic eruption of the maxillary first permanent molar.

The aim of this study was to determine the prevalence of ectopic eruption of the upper first permanent molar and to investigate the morphological characteristics of affected cases. Three groups of children were compared using Ricketts' cephalometric analysis. Group I consisted of 26 patients aged 6 to 11 years with ectopic eruption of the first molars. Group II consisted of 45 cases aged 12 to 17 years with ideal occlusion, and Group III consisted of 50 orthodontic patients aged 8 to 18 chosen at random. In the ectopic group the maxilla appears to be situated further back and facial convexity is reduced. The use of extra-oral forces to correct the mesial position of the ectopic first permanent molars is not appropriate and appliances using reciprocal intramaxillary forces would be more suitable.
Somatosensory mismatch negativity in healthy children

Aim Event‐related potentials (ERPs) obtained when focused attention is kept away from the stimulus (unnoticed stimulation) are possibly linked to automatic mismatch‐detection mechanisms, and could be a useful tool to investigate sensory discrimination ability. By considering the high impact of impaired somatosensory integration on many neurological disturbances in children, we aimed to verify whether mismatch‐related responses to somatosensory stimulation could be obtained in healthy children.
Comparison of Protein Fouling on Heat‐Treated Poly(vinyl alcohol), Poly(ether sulfone) and Regenerated Cellulose Membranes Using Diffuse Reflectance Infrared Fourier Transform Spectroscopy

Poly(vinyl alcohol) (PVA) membranes for ultrafiltration were fabricated by heat‐treatment to separate macromolecules from microsolutes. PVA is a hydrophilic polymer with good mechanical properties because of its semicrystalline structure. The membranes were heat‐treated at 100 °C for 1 h to increase their crystallinity and thereby their mechanical strength. The mechanical strength of the membranes was evaluated using a dynamic mechanical analyzer by measuring their compressive and tensile moduli. Membrane selectivities and protein fouling of heat‐treated PVA membranes were compared to the commercial poly(ether sulfone) (PeS) and regenerated cellulose membranes. Myoglobin from horse skeletal muscle was used as a model protein, and L‐tryptophan was used as a model microsolute. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was used to identify protein fouling on the surfaces of these membranes under flow and nonflow conditions. It was found from the selectivity and DRIFTS studies that PVA membranes were more resistant to fouling than regenerated cellulose and PeS membranes.