Miracle-dz/UniFAR-FTUs huggingface dataset:
Constant switching frequency techniques for sliding mode control in DC-DC converters

Sliding mode is a very effective control strategy for switch mode DC-DC converters. However, its widespread adoption has been hampered by some of the drawbacks inherent to this control technique. Among these, the most important is apparently the varying operating frequency, which can cause electromagnetic-interference (EMI) problems. This problem is particularly critical in portable devices (e.g. smartphones, e-readers) where it is highly desirable that the DC-DC converters operate at a constant switching frequency to avoid interferences with other parts of the system. Several methods have been proposed in previous literature to stabilize the operating frequency of sliding mode controllers. In this paper, some of the most promising techniques are evaluated and applied to a specific test-case, i.e. a Buck converter for a wireless system. A detailed model of the DC-DC converter has been developed in order to obtain realistic results. The system parameters have been chosen to reflect an actual commercial application.
Learning with Mobiles in Developing Countries: Technology, Language, and Literacy

In the countries of the global South, the challenges of fixed infrastructure and environment, the apparent universality of mobile hardware, software and network technologies and the rhetoric of the global knowledge economy have slowed or impoverished the development of appropriate theoretical discourses to underpin learning with mobiles. This paper addresses one specific and fundamental component of such discourses, namely the role of language and literacy as they interact with mobile technology. The paper makes three points, that mobile technology is culturally and linguistically specific, not universal or culturally-neutral; that mobile technology does not merely store and transmit languages and literacy within communities, it disturbs and transforms them, and that the digital literacy agenda that might underpin learning with mobiles has not yet been developed in relation to mobile technology or in relation to the global South. These are the foundations of understanding learning with mobiles in the global South.
The oocyte population is not renewed in transplanted or irradiated adult ovaries.

BACKGROUND According to conventional theory, the oocyte population is not renewed in mammalian ovaries after birth. A new hypothesis proposes that oocytes are generated continuously from haematopoietic progenitor cells. There is, however, no evidence that they can ovulate, although they may partially restore fertility by organizing 'helper follicles'. The hypothesis that follicles can form de novo in adult ovaries has been tested in a transplant model. METHODS Ovaries from adult mice were transplanted under the kidney capsule or into the ovarian bursa of histocompatible, transgenic CAG::H2B-EGFP host animals. Some donors were sterilized before transplantation by X-irradiation to ensure 'empty niches' were available for repopulation. The phenotype of follicular oocytes at 2, 4 and 8 weeks post-transplantation was scored by epifluorescence. RESULTS A total of 819 oocytes were examined in 30 ovarian grafts. None expressed green fluorescence, as would be predicted if they had formed de novo from germ cell progenitors in the systemic circulation of the host. Furthermore, small follicles eliminated by irradiation were not replaced in transplanted ovaries, and the few growing follicles present were apparently survivors of the original population. CONCLUSIONS No evidence was found to support the hypothesis that progenitor cells from extra-ovarian sources can repopulate the adult ovary. The findings are consistent with the conventional view that a limited number of oocytes are formed before birth and declines with age. The study did not, however, rule out the possibility that germline stem cells may reside in the adult ovary.
A uniquely adaptable pore is consistent with NALCN being an ion sensor

NALCN is an intriguing, orphan ion channel among the 4x6TM family of related voltage-gated cation channels, sharing a common architecture of four homologous domains consisting of six transmembrane helices, separated by three cytoplasmic linkers and delimited by N and C-terminal ends. NALCN is one of the shortest 4x6TM family members, lacking much of the variation that provides the diverse palate of gating features, and tissue specific adaptations of sodium and calcium channels. NALCN’s most distinctive feature is that that it possesses a highly adaptable pore with a calcium-like EEEE selectivity filter in radially symmetrical animals and a more sodium-like EEKE or EKEE selectivity filter in bilaterally symmetrical animals including vertebrates. Two lineages of animals evolved alternative calcium-like EEEE and sodium-like EEKE / EKEE pores, spliced to regulate NALCN functions in differing cellular environments, such as muscle (heart and skeletal) and secretory tissue (brain and glands), respectively. A highly adaptable pore in an otherwise conserved ion channel in the 4x6TM channel family is not consistent with a role for NALCN in directly gating a significant ion conductance that can be either sodium ions or calcium ions. NALCN was proposed to be an expressible Gd3+-sensitive, NMDG+-impermeant, non-selective and ohmic leak conductance in HEK-293T cells, but we were unable to distinguish these reported currents from leaky patch currents (ILP) in control HEK-293T cells. We suggest that NALCN functions as a sensor for the much larger UNC80/UNC79 complex, in a manner consistent with the coupling mechanism known for other weakly or non-conducting 4x6TM channel sensor proteins such as Nax or Cav1.1. We propose that NALCN serves as a variable sensor that responds to calcium or sodium ion flux, depending on whether the total cellular current density is generated more from calcium-selective or sodium-selective channels.
GDP-mannose pyrophosphorylase is a genetic determinant of ammonium sensitivity in Arabidopsis thaliana

Higher plant species differ widely in their growth responses to ammonium (NH4+). However, the molecular genetic mechanisms underlying NH4+ sensitivity in plants remain unknown. Here, we report that mutations in the Arabidopsis gene encoding GDP-mannose pyrophosphorylase (GMPase) essential for synthesizing GDP-mannose confer hypersensitivity to NH4+. The in planta activities of WT and mutant GMPases all were inhibited by NH4+, but the magnitude of the inhibition was significantly larger in the mutant. Despite the involvement of GDP-mannose in both l-ascorbic acid (AsA) and N-glycoprotein biosynthesis, defective protein glycosylation in the roots, rather than decreased AsA content, was linked to the hypersensitivity of GMPase mutants to NH4+. We conclude that NH4+ inhibits GMPase activity and that the level of GMPase activity regulates Arabidopsis sensitivity to NH4+. Further analysis showed that defective N-glycosylation of proteins, unfolded protein response, and cell death in the roots are likely important downstream molecular events involved in the growth inhibition of Arabidopsis by NH4+.
Using sodium molybdate to treat chronic copper toxicity in dairy cows: A practical approach

Abstract CASE HISTORY: A Jersey herd of 350 cows and 70 heifers located in the Taranaki region of New Zealand ceased milking in June 2011. Ten cows died during the subsequent 14 days. For at least 9 months, the cows had received palm kernel expeller (PKE) and molasses supplements. Additional Cu supplementation was provided through the water system. Total Cu intake was calculated to be 400 mg/day/cow. CLINICAL AND PATHOLOGICAL FINDINGS: Half of the cows died suddenly while others presented with anorexia, depression and ataxia, which progressed to recumbency and death after 1 to 3 days. Clinical signs were mild dehydration, cyanosis and firm faeces which were covered in dark blood. Mean concentrations of Cu in liver and kidney in three of the dead cows were 3,900 and 440 µmol/kg fresh weight (FW), respectively. Haemorrhages were observed throughout the alimentary tracts and in muscles, and there were ecchymotic haemorrhages on the epi- and endocardia. The livers were swollen and the gall bladder walls were inflamed. DIAGNOSIS: High concentrations of Cu in the liver and kidney are characteristic findings of chronic Cu toxicity. TREATMENT: The remaining herd was fed 200 mg Mo, as sodium molybdate, per cow per day and all Cu supplements were removed including those provided by the water supply. This reduced mean concentrations of Cu in liver from 3,100 to 1,320 µmol/kg FW within 26 days in the five live animals that were biopsied. There were no further deaths. CLINICAL RELEVANCE: In dairy herds where excessive Cu intakes have resulted in high liver Cu concentrations and caused chronic Cu toxicity, the removal of all Cu supplements and provision of high intakes of Mo (200 mg/cow/day) can markedly reduce liver Cu stores within 4 weeks.
Co-localization of Racl and E-Cadherin in Human Epidermal Keratinocytes

The Racl small GTP-binding protein is known to be involved in reorganization of the actin cytoskeleton and in regulation of intracellular signal transduction. The assembly and maintenance of cadherin-based cell-cell junctions in epidermal keratinocytes is thought to be dependent on activity of Racl. In this study we have generated green fluorescent protein (GFP)-tagged wild type, dominant negative and constitutively active Racl expression vectors and analyzed distribution of Racl following microinjection of human SCC12F epidermal keratinocytes. Wild type, dominant negative and constitutively active GFP-Racl proteins distribute to sites of cell-cell adhesion and co-localize with E-cadherin and the catenins. Disruption of cadherin-based junctions by reduction in extracellular calcium concentrations, or by use of antibodies to E-cadherin, results in redistribution of Racl away from sites of cell-cell interaction but the co-localization with E-cadherin is maintained. In addition, expression of constitutively active GFP-Racl results in formation of membrane ruffles on the apical surface of cells and intracellular vesicles. Interestingly, co-localization of Racl with E-cadherin is maintained in these structures. In contrast to previously published work we find that expression of dominant negative Racl neither disrupts cell-cell adhesion nor prevents assembly of new cadherin-based adhesion structures.
The Socioeconomic Gradient in the Incidence of Stroke: A Prospective Study in Middle-Aged Women in Sweden

Background and Purpose— A socioeconomic gradient in stroke has been demonstrated in a variety of settings, but mostly in men. Our purpose was to establish whether a socioeconomic gradient in stroke existed in a group of Swedish women and whether this gradient could be explained by established stroke risk factors or psychosocial factors. Methods— The Women's Lifestyle and Health Cohort Study includes 49 259 women from Sweden aged 30 to 50 years at baseline (1991 to 1992). The women completed an extensive questionnaire and were traced through linkages to national registries until the end of 2002. Among the 47 942 women included in these analyses, there were 200 cases of incident stroke during follow up (121 ischemic stroke, 47 hemorrhagic stroke, and 32 of unknown origin). Statistical analysis was through the Cox proportional hazards model. Results— The risk of stroke was significantly inversely related to years of education completed, our proxy for socioeconomic status (hazard ratio comparing lowest with highest education group=2.1, 95% CI: 1.4 to 2.9, P for trend <0.001). This association was reduced after adjustment for established risk factors, although remaining significant (1.5, 1.0 to 2.2, P for trend=0.04). The gradient was more pronounced for ischemic stroke (2.9, 1.8 to 4.7, P for trend <0.001) than for hemorrhagic stroke (1.4, 0.7 to 2.9, P for trend=0.35). Job strain and social support were unrelated to risk of stroke. Self-rated health was strongly related to risk of stroke mediated by established risk factors. Psychosocial factors did not contribute toward the socioeconomic gradient in stroke. Conclusions— There was a strong gradient in risk of stroke by years of education, especially for ischemic stroke. Most of the social gradient was explained by established risk factors, particularly smoking and alcohol, but not by psychosocial factors.
[Assessment of chosen cognitive functions in children and adolescents with primary headaches].

BACKGROUND Foundations and aim of the study: Right development of cognitive functions is one of the basal factors, which determines good realization of the developmental tasks, for example achievement in education. Primary headaches especially migraine can be one of the important factor disturbing cognitive functioning of children and adolescents. The aim of the study was to estimate the level of some chosen aspects of cognitive and intellectual functioning of children and adolescents with primary headaches: migraine and tension type (TTH). MATERIAL AND METHODS 90 patients with migraine and 35 with TTH were diagnosed according to the classification of the International Headache Society (IHS 2004). Both groups matched each other according to distribution and averages in sex, age, age of the disease occurrence and time of its duration. The methods used in the study were Raven Test (intelligence), Benton Visual Retention Test form C and D, method A (short term memory for visual modality), Ten Words Test as a shortened version of RAVLT (abilities of learning processes and memory), Loretta Bender Gestalt Test and Bender-Koppitz Test (visuomotor integration and visual perception). RESULTS The significant difference in the level of intelligence was stated between the examined groups. Children with migraine, especially without aura, in comparison to peers with TTH reached better results in Raven Test. The analysis of the results of the Benton Test in the number of correct and incorrect reproduced tables shows that children with migraine have poorer results. The percentage of correct answers in area of the level of visuomotor intergration was lower in the group with migraine (64%) than in the group with TTH (76%). Patients with migraine mainly with aura (41%) got lower results in Ten Word Test, which estimates the sum of gained results in five trials, and a percentage of correct answers in comparison to the group with TTH (60%). CONCLUSIONS Patients with migraine in comparison to children with TTH show important disturbances in ability of short-term visual memory and visuomotor integration. Diagnosed selected cognitive dysfunctions in children with primary headaches can disturb accomplishment of tasks connected with education but they do not have any important influence on general intellectual functioning.
Identification of macroscopic feedback gain in a position-controlled humanoid robot and its application to falling detection

Motion control of a humanoid robot is challenging problem because its dynamics is complicated. To make it easier to design a controller, a macroscopic dynamics focusing on the relationship between the center of gravity (COG) and the center of pressure (COP) is often used. Based on the COG-COP model, it is possible to control the COG by using the COP as the control input. Moreover, it is possible to detect falling based on the Maximal Output Admissible (MOA) set as the author presented in the previous paper. However, generating appropriate control input (COP) requires sophisticated joint actuator which can realize torque control and backdrivability. Research on this type of actuators is still on-going in the robotics field, and most existing humanoid robots are position-controlled. In this paper, the author identifies a macroscopic feedback gain in a position-controlled humanoid by measuring a disturbance response. From the obtained feedback gain, it is possible to compute the MOA set and apply it to the falling prevention control. The effectiveness of the proposed method is verified with experiments.
Intracranial hemorrhage in asymptomatic neonates: prevalence on MR images and relationship to obstetric and neonatal risk factors.

PURPOSE To retrospectively evaluate the prevalence of neonatal intracranial hemorrhage (ICH) and its relationship to obstetric and neonatal risk factors. MATERIALS AND METHODS Pregnant women were recruited for a prospective study of neonatal brain development; the study was approved by the institutional review board and complied with HIPAA regulations. After informed consent was obtained from a parent, neonates were imaged with 3.0-T magnetic resonance (MR) imaging without sedation. The images were reviewed by a neuroradiologist with 12 years of experience for the presence of ICH. Medical records were prospectively and retrospectively reviewed for selected risk factors, which included method of delivery, duration of labor, and evidence of maternal or neonatal birth trauma. Risk factors were assessed for relationship to ICH by using Fisher exact test statistics. RESULTS Ninety-seven neonates (mean age at MR imaging, 20.8 days +/- 6.9 [standard deviation]) underwent MR imaging between the ages of 1 and 5 weeks. Eighty-eight (44 male and 44 female) neonates (65 with vaginal delivery and 23 with cesarean delivery) completed the MR imaging evaluation. Seventeen neonates with ICHs (16 subdural, two subarachnoid, and six parenchymal hemorrhages) were identified. Seven infants had two or more types of hemorrhages. All neonates with ICH were delivered vaginally, with a prevalence of 26% in vaginal births. ICH was significantly associated with vaginal birth (P < .005) but not with prolonged duration of labor or with traumatic or assisted vaginal birth. CONCLUSION Asymptomatic ICH following vaginal birth in full-term neonates appears to be common, with a prevalence of 26% in this study.
Q-TWiST analysis of panitumumab plus FOLFOX4 versus FOLFOX4 alone in patients with previously untreated wild-type RAS metastatic colorectal cancer

Abstract Introduction: Panitumumab plus infusional 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX4) significantly improved overall survival versus FOLFOX4 alone in patients with previously untreated wild-type RAS metastatic colorectal cancer (mCRC). We applied a quality-adjusted time without symptoms of disease or toxicity (Q-TWiST) analysis to provide an integrated measure of clinical benefit, with the objective of comparing quality-adjusted survival between the two arms. We acknowledge that there are limitations associated with Q-TWIST methodology for crossover trials. Methods: For each treatment arm, the truncated mean times spent in the toxicity (TOX: grade 3 or 4 adverse events), time without symptoms of disease or toxicity (TWiST), and relapse (REL: after disease progression) states were estimated by the product-limit method, and adjusted using utility weights derived from patient-reported EuroQol 5-dimension measures. Sensitivity analyses were performed in which utility weights (varying from 0 to 1) were applied to time in the TOX and REL health states. Results: Quality-adjusted overall survival time was statistically significantly longer with panitumumab plus FOLFOX4 (20.5 months) than with FOLFOX4 alone (18.2 months) (P = 0.025). Conclusion: In patients with previously untreated wild-type RAS mCRC, panitumumab plus FOLFOX4 significantly improved quality-adjusted survival compared with FOLFOX4 alone.
Financial services system for the effect of corporate financing efficiency during the development of headquarter economy in Xi'an Hi-Tech Industries Development Zone

The paper started from analyzing the background of the development of headquarter economy in Xi'an Hi-Tech Industries Development Zone (“Xi'an High-tech Zone” for short) and the literature review of financing efficiency , and took the effect that financial services system had on corporate financial efficiency as the research object. The research took high-tech enterprises, financial institutions' staff and financial research scholars as main research subject, through the interviews, questionnaire survey, product-moment correlation analysis and canonical correlation analysis to verify the correlated hypothesis. The financial services system includes A-financial macro-policy environment, B-financial industry's supporting platform, C-indirect financing system (including the banking system, the insurance market), and D-capital market financing system. The results show that there is a significant positive correlation relation between the financial services system, its sub-system and the corporate financial efficiency of the region.
Activation of Hypoxia-inducible Factor-1; Definition of Regulatory Domains within the α Subunit*

Hypoxia-inducible factor-1 (HIF-1), a heterodimeric DNA binding complex composed of two basic-helix-loop-helix Per-AHR-ARNT-Sim proteins (HIF-1α and −1β), is a key component of a widely operative transcriptional response activated by hypoxia, cobaltous ions, and iron chelation. To identify regions of HIF-1 subunits responsible for oxygen-regulated activity, we constructed chimeric genes in which portions of coding sequence from HIF-1 genes were either linked to a heterologous DNA binding domain or encoded between such a DNA binding domain and a constitutive activation domain. Sequences from HIF-1α but not HIF-1β conferred oxygen-regulated activity. Two minimal domains within HIF-1α (amino acids 549-582 and amino acids 775-826) were defined by deletional analysis, each of which could act independently to convey inducible responses. Both these regions confer transcriptional activation, and in both cases adjacent sequences appeared functionally repressive in transactivation assays. The inducible operation of the first domain, but not the second, involved major changes in the level of the activator fusion protein in transfected cells, inclusion of this sequence being associated with a marked reduction of expressed protein level in normoxic cells, which was relieved by stimulation with hypoxia, cobaltous ions, or iron chelation. These results lead us to propose a dual mechanism of activation in which the operation of an inducible activation domain is amplified by regulation of transcription factor abundance, most likely occurring through changes in protein stability.
Postural reactions to neck vibration in Parkinson's disease

To test the hypothesis that reduced reactions to proprioceptive input signals contribute to postural instability in Parkinson's disease (PD), pulses of mechanical vibration were applied to the neck muscles of PD patients and healthy controls. This stimulus elicits postural reactions in standing subjects. Participating were 13 moderately affected PD patients, 13 severely affected PD patients, and 13 age‐matched healthy subjects. Patients were tested on and off medication. Three‐second‐long pulses of vibration were regularly (10 times) applied to the posterior neck muscles while subjects kept their eyes open or closed. Postural responses to the stimuli were measured by static posturography. No intergroup difference in the pattern and latencies of responses was found. However, the amplitudes of the postural reactions (shift of center of foot pressure) were significantly larger in advanced PD patients; those of moderately affected PD patients did not differ from those of control subjects. Moreover, the size of postural responses in both latter groups decreased across the trial contrary to that of advanced PD patients. Comparison of the measures during on and off testing revealed no significant differences. These results indicate that neither afferent proprioceptive deficits nor central integrative functions but rather scaling and habituation of erroneous proprioceptive information are disturbed in the postural control of advanced PD. Nondopaminergic structures seem to be responsible for this impairment. © 2005 Movement Disorder Society