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1.
Mol Phylogenet Evol ; 196: 108067, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38561082

ABSTRACT

In the species groups related to Diphasiastrum multispicatum and D. veitchii, hybridization was investigated in samples from northern and southern Vietnam and the island of Taiwan, including available herbarium specimens from southeast Asia. The accessions were analyzed using flow cytometry (living material only), Sanger sequencing and multiplexed inter-simple sequence repeat genotyping by sequencing. We detected two cases of ancient hybridization involving different combinations of parental species; both led via subsequent duplication to tetraploid taxa. A cross D. multispicatum × D. veitchii from Malaysia represents D. wightianum, a tetraploid taxon according to reported DNA content measurements of dried material (genome formulas MM, VV and MMVV, respectively). The second case involves D. veitchii and an unknown diploid parent (genome formula XX). Three hybridogenous taxa (genome formulas VVX, VVXX, VVVX) were discernable by a combination of flow cytometry and molecular data. Taxon I (VVX, three clones found on Taiwan island) is apparently triploid. Taxon II represents another genetically diverse and sexual tetraploid species (VVXX) and can be assigned to D. yueshanense, described from Taiwan island but occurring as well in mainland China and Vietnam. Taxon III is as well most likely tetraploid (VVVX) and represented by at least one, more likely two, clones from Taiwan island. Taxa I and III are presumably asexual and new to science. Two independently inherited nuclear markers recombine only within, not between these hybrids, pointing towards reproductive isolation. We present an evolutionary scheme which explains the origin of the hybrids and the evolution of new and fully sexual species by hybridization and subsequent allopolyploidization in flat-branched clubmosses.


Subject(s)
Hybridization, Genetic , Lycopodiaceae , Phylogeny , Taiwan , Vietnam , Lycopodiaceae/genetics , Lycopodiaceae/classification , DNA, Plant/genetics , Microsatellite Repeats , Sequence Analysis, DNA , Islands , Evolution, Molecular , Genome, Plant , Flow Cytometry
2.
Neuromuscul Disord ; 32 Suppl 1: S84, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36280381

ABSTRACT

The publisher regrets that this article has been temporarily removed. A replacement will appear as soon as possible in which the reason for the removal of the article will be specified, or the article will be reinstated. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

3.
J Prev Alzheimers Dis ; 4(2): 87-92, 2017.
Article in English | MEDLINE | ID: mdl-28966919

ABSTRACT

BACKGROUND: Practice effects, which are improvements in cognitive test scores due to repeated exposure to testing materials, may provide information about Alzheimer's disease pathology, which could be useful for clinical trials enrichment. OBJECTIVES: The current study sought to add to the limited literature on short-term practice effects on cognitive tests and their relationship to amyloid deposition on neuroimaging. PARTICIPANTS: Twenty-seven, non-demented older adults (9 cognitively intact, 18 with mild cognitive impairment) received amyloid imaging with 18F-Flutemetamol, and two cognitive testing sessions across one week to determine practice effects. RESULTS: A composite measure of 18F-Flutemetamol uptake correlated significantly with all seven cognitive tests scores on the baseline battery (r's = -0.61 - 0.59, all p's<0.05), with higher uptake indicating poorer cognition. Practice effects significantly added to the relationship (above and beyond the baseline associations) with 18F-Flutemetamol uptake on 4 of the 7 cognitive test scores (partial r's = -0.45 - 0.44, p's<0.05), with higher uptake indicating poorer practice effects. The odds ratio of being "amyloid positive" was 13.5 times higher in individuals with low practice effects compared to high practice effects. CONCLUSIONS: Short-term practice effects over one week may be predictive of progressive dementia and serve as an affordable screening tool to enrich samples for preventative clinical trials in Alzheimer's disease.

4.
J Wound Care ; 26(8): 462-468, 2017 08 02.
Article in English | MEDLINE | ID: mdl-28795887

ABSTRACT

OBJECTIVE: Cold atmospheric pressure plasmas (CAPPs) have been used to sterilise implant materials and other thermally unstable medical products and to modify chemical surfaces. This study investigates the antimicrobial effect of the gas and input power used to generate CAPPs on microorganisms causing skin infections, such as Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Malassezia pachydermatis. METHOD: Microorganisms were cultivated on Mueller Hinton 2 (MH2) agar plates. CAPP treatment was performed using the Plasma BLASTER MEF. To investigate the antimicrobial effects the following CAPP parameters were varied: the gas used, input power, as well as number of treatments and treatment time. RESULTS: The antimicrobial efficacy of the CAPPs was found to increase with increasing input power and treatment time (or cycles). Furthermore the plasma generated from nitrogen is more effective than from air. CONCLUSION: The study showed that CAPPs demonstrate strong bactericidal and fungicidal properties in vitro. The selective application of CAPPs for the treatment of wound infections may offer a promising supplementary tool alongside current therapies.


Subject(s)
Air , Atmospheric Pressure , Candida albicans/drug effects , Cold Temperature , Malassezia/drug effects , Nitrogen/pharmacology , Plasma Gases/pharmacology , Pseudomonas aeruginosa/drug effects , Skin Diseases, Infectious/microbiology , Staphylococcus aureus/drug effects , Time Factors
5.
Br J Psychol ; 108(3): 544-563, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27620075

ABSTRACT

The concept of learning style is immensely popular despite the lack of evidence showing that learning style influences performance. This study tested the hypothesis that the popularity of learning style is maintained because it is associated with subjective aspects of learning, such as judgements of learning (JOLs). Preference for verbal and visual information was assessed using the revised Verbalizer-Visualizer Questionnaire (VVQ). Then, participants studied a list of word pairs and a list of picture pairs, making JOLs (immediate, delayed, and global) while studying each list. Learning was tested by cued recall. The results showed that higher VVQ verbalizer scores were associated with higher immediate JOLs for words, and higher VVQ visualizer scores were associated with higher immediate JOLs for pictures. There was no association between VVQ scores and recall or JOL accuracy. As predicted, learning style was associated with subjective aspects of learning but not objective aspects of learning.


Subject(s)
Cognition/physiology , Judgment/physiology , Learning/physiology , Acoustic Stimulation , Adolescent , Cues , Female , Humans , Mental Recall/physiology , Photic Stimulation , Surveys and Questionnaires , Time Factors , Young Adult
6.
Prev Med Rep ; 2: 423-8, 2015.
Article in English | MEDLINE | ID: mdl-26844100

ABSTRACT

UNLABELLED: College students engage in many unhealthy behaviors, one of these, heavy alcohol use, is a major global public health problem. OBJECTIVE: This longitudinal study examined whether students' mandated/voluntary status in a program to reduce college drinking was associated with overall health, ethnicity, gender, and personality traits. Both mandated and voluntary groups participated in the Motivational Intervention (MI) program to prevent high risk drinking. METHODS: Freshmen (710 voluntary, 190 mandated, n = 900) between the ages of 18 and 21, received the MI at baseline and again at 2 weeks, with boosters at 3, 6 and 12 months. Participants completed three measures: the Daily Drinking Questionnaire (DDQ); the Substance Use Risk Profile Scale (SURPS), and the Health Promoting Lifestyle Profile II (HPLPII). Mandated and voluntary participants were compared at baseline and following the intervention using two sample t-tests for continuous variables (overall health, personality traits, drinking measures), and chi-square for categorical variables (gender, ethnicity). Linear mixed models were used to identify associations between HPLP II scores and mandated/voluntary status, time, ethnicity gender and SURPS scale scores. RESULTS: In both groups, alcohol consumption dropped significantly by 12 months. Overall health-promoting behaviors, physical activity, stress management, and interpersonal relations improved in both groups between baseline and 12 months. Associations were found between alcohol consumption, personality traits, gender, and lifestyle health-promoting behaviors. In particular, impulsivity and hopelessness were associated with poor health behaviors. CONCLUSIONS: Intervention programs to reduce drinking by college students need to address developmental dynamics of freshmen students, including gender, psychosocial factors, personality, and lifestyle health-promoting behaviors.

7.
Sci Rep ; 4: 5704, 2014 Jul 16.
Article in English | MEDLINE | ID: mdl-25027748

ABSTRACT

Understanding the nature of the interaction at the graphene/metal interfaces is the basis for graphene-based electron- and spin-transport devices. Here we investigate the hybridization between graphene- and metal-derived electronic states by studying the changes induced through intercalation of a pseudomorphic monolayer of Cu in between graphene and Ir(111), using scanning tunnelling microscopy and photoelectron spectroscopy in combination with density functional theory calculations. We observe the modifications in the band structure by the intercalation process and its concomitant changes in the charge distribution at the interface. Through a state-selective analysis of band hybridization, we are able to determine their contributions to the valence band of graphene giving rise to the gap opening. Our methodology reveals the mechanisms that are responsible for the modification of the electronic structure of graphene at the Dirac point, and permits to predict the electronic structure of other graphene-metal interfaces.

8.
J Psychosoc Nurs Ment Health Serv ; 52(7): 38-45, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24627978

ABSTRACT

Drinking is pervasive in the lifestyle of many college students. This study investigated the relationship between drinking and students' impulsivity, sensation seeking, alcohol consequences, and expectancies. The study was based on the Acquired Preparedness Model, which posits that personality constructs like impulsivity and sensation seeking influence drinking through the formation of positive expectancies about the effects of drinking. Freshmen (N = 260) from a large public university volunteered for the study and were administered three surveys. Structural equation modeling was used to examine the study variables. The findings showed that the total effect of impulsivity was mediated by positive alcohol expectancies. The total effect of sensation seeking was mediated by alcohol expectancies. Freshmen who were more impulsive and sensation seeking had more positive alcohol expectancies and experienced more negative consequences related to alcohol use. These findings suggest that the risk of alcohol consequences was associated with personality constructs and alcohol expectancies.


Subject(s)
Alcohol Drinking/psychology , Impulsive Behavior , Personality Assessment , Students/psychology , Universities , Adolescent , Education, Nursing, Continuing , Female , Humans , Male , Risk Factors , Risk-Taking , Surveys and Questionnaires , Young Adult
9.
Skin Pharmacol Physiol ; 27(1): 25-35, 2014.
Article in English | MEDLINE | ID: mdl-23921169

ABSTRACT

OBJECTIVES: Plasma medicine focuses on the application of cold atmospheric pressure plasmas (CAPs) in or on the human body. So far, plasmas have been used to sterilize implant materials or other thermally unstable medical products and have been applied for chemical surface modifications. This study investigates the antimicrobial effect of physical plasmas on microorganisms which cause skin infections, such as Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, depending on the plasma source and the kind of plasma excitation used. MATERIALS: Microorganisms were plated onto MH2 agar plates. Plasma treatment was performed using the plasma sources BLASTER MEF and kinpen 09. To investigate the antimicrobial effects, the following plasma parameters have been varied: working gas, distance from nozzle to surface, electrical power, grid spacing of treatment lines, number of treatments and work piece velocity. RESULTS: The generated plasmas had an antimicrobial effect that depended on the chosen plasma parameters, in particular on the process gas used, the plasma power and the number of treatments performed. Thus, different reactive species were observed by optical emission spectroscopy measurement in the generated plasmas. CONCLUSIONS: The study showed that CAPs exhibit profound bactericidal and fungicidal properties in vitro. However, an important factor for the antimicrobial efficacy is the composition of the 'chemical soup' supplied by the CAP system which can be regulated by the process gases used.


Subject(s)
Anti-Infective Agents/pharmacology , Candida albicans/drug effects , Plasma Gases/pharmacology , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Air , Argon/pharmacology , Candida albicans/growth & development , Nitrogen/pharmacology , Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/growth & development
10.
Anaesthesia ; 68(9): 899-903, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23789738

ABSTRACT

We undertook a randomised, controlled trial to compare the analgesic efficacy and opioid sparing effect of nerve stimulator-guided femoral nerve block with fascia iliaca compartment block in patients awaiting surgery for fractured neck of femur. Ten-centimetre visual analogue pain scores were measured before and 2 h after the block and opioid consumption was recorded in the 12-h period after the block. One hundred and ten patients were randomly assigned. Femoral nerve block provided superior pre-operative analgesia for fractured neck of femur compared with fascia iliaca compartment block. The difference in the mean reduction of pain score after the block was 0.9 (95% CI 0-1.8); p = 0.047. Patients receiving a femoral nerve block required less morphine after the block than those receiving fascia iliaca compartment block (p = 0.041).


Subject(s)
Femoral Neck Fractures/surgery , Nerve Block/methods , Pain/drug therapy , Preoperative Care/methods , Aged , Aged, 80 and over , Analgesics, Opioid/administration & dosage , Anesthetics, Local , Bupivacaine/analogs & derivatives , Electric Stimulation/methods , Fascia , Female , Femoral Nerve , Humans , Levobupivacaine , Male , Middle Aged , Pain Management/methods , Pain Measurement/methods
11.
Rev Pneumol Clin ; 69(5): 244-9, 2013 Oct.
Article in French | MEDLINE | ID: mdl-23796499

ABSTRACT

According to UN, Cambodia is one of the poorest countries in the World. Respiratory diseases are current public health priorities. In this context, a new bronchoscopy unit (BSU) was created in the respiratory medicine department of Preah Kossamak hospital (PKH) thanks to a tight cooperation between a French and a Cambodian team. Aim of this study was to describe conditions of introduction of this equipment. Two guidelines for practice are available. They are respectively edited by the French and British societies of pulmonology. These guidelines were reviewed and compared to the conditions in which BS was introduced in PKH. Each item from guidelines was combined to a categorical value: "applied", "adapted" or "not applied". In 2009, 54 bronchoscopies were performed in PKH, mainly for suspicion of infectious or tumour disease. In total, 52% and 46% of the French and British guideline items respectively were followed in this Cambodian unit. Patient safety items are those highly followed. By contrast "staff safety" items were those weakly applied. Implementation of EBS in developing countries seems feasible in good conditions of quality and safety for patients. However, some recommendations cannot be applied due to local conditions.


Subject(s)
Bronchoscopy/standards , Developing Countries , Guideline Adherence , Health Plan Implementation , Hospital Units/standards , Poverty , Bronchoscopy/adverse effects , Cambodia , Decontamination/standards , Developing Countries/economics , Female , Guideline Adherence/economics , Guideline Adherence/statistics & numerical data , Health Plan Implementation/economics , Health Plan Implementation/standards , Humans , Male , Middle Aged , Patient Safety/standards , Practice Guidelines as Topic
12.
J Physiol ; 591(22): 5475-89, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-23027819

ABSTRACT

Cerebellar climbing fibres originate in the inferior olive (IO). Temporary IO inactivation produces movement deficits. Does permanent inactivation produce similar deficits and, if so, do they recover? The excitotoxin, kainic acid, was injected into the rostral IO of three cats. Behaviour was measured during reaching and locomotion. Two cats were injected during the reaching task. Within minutes, grasping became difficult and the trajectories of the reaches showed higher arcing than normally seen. During locomotion, both cats showed head and trunk deviation to the injected side, walking paths curved to the injected side, and the paws were lifted higher than normal. Limbs contralateral to the injections became rigid. Within 1 day, posture had normalized, locomotion was unsteady and high lifting of the paws had reversed to a tendency to drag the dorsum of the paws. Passive body movement produced vestibular signs. Over a few days, locomotion normalized and vestibular signs disappeared. Reach trajectories were normal but grasping deficits persisted. Over the first week, the amplitude of limb lift during reaching and locomotion began to increase. The increase continued over time and, after several months, limb movements became severely ataxic. The effects followed the somatotopy of the rostral IO: a loss of cells in medial rostral IO only affected the forelimb, whereas a loss of cells in medial and lateral IO affected both forelimb and hindlimb. Deficits produced by IO lesions involve multiple mechanisms; some recover rapidly, some appear stable, and some worsen over time. The nature of the progressive deficit suggests a gradual loss of Purkinje cell inhibition on cerebellar nuclear cells.


Subject(s)
Ataxia/physiopathology , Forelimb/physiology , Hindlimb/physiology , Olivary Nucleus/physiology , Animals , Cats , Cerebellar Cortex/physiology , Cerebellum/physiology , Locomotion/physiology , Male , Movement/physiology , Neural Pathways/physiology , Posture/physiology , Purkinje Cells/physiology
13.
Phys Rev Lett ; 109(21): 216403, 2012 Nov 21.
Article in English | MEDLINE | ID: mdl-23215602

ABSTRACT

We use hard x-ray photoemission to resolve a controversial issue regarding the mechanism for the formation of quasicrystalline solids, i.e., the existence of a pseudogap at the Fermi level. Our data from icosahedral fivefold Al-Pd-Mn and Al-Cu-Fe quasicrystals demonstrate the presence of a pseudogap, which is not observed in surface sensitive low energy photoemission because the spectrum is affected by a metallic phase near the surface. In contrast to Al-Pd-Mn, we find that in Al-Cu-Fe the pseudogap is fully formed; i.e., the density of states reaches zero at E(F) indicating that it is close to the metal-insulator phase boundary.

14.
Br J Cancer ; 106(11): 1742-52, 2012 May 22.
Article in English | MEDLINE | ID: mdl-22538973

ABSTRACT

BACKGROUND: Newly diagnosed patients with chronic myeloid leukaemia (CML) are currently treated with tyrosine kinase inhibitors (TKIs) such as imatinib, nilotinib or dasatinib. However, incomplete eradication of residual disease is a general problem of long-term TKI therapy. Activation of mouse haematopoietic stem cells by interferon-α (IFNα) stimulated the discussion of whether a combination treatment leads to accelerated eradication of the CML clone. METHODS: We base our simulation approach on a mathematical model describing human CML as a competition phenomenon between normal and malignant cells. We amend this model to incorporate the description of IFNα activity and simulate different scenarios for potential treatment combinations. RESULTS: We demonstrate that the overall sensitivity of CML stem cells to IFNα activation is a crucial determinant for the benefit of a potential combination therapy. We furthermore show that pulsed IFNα together with continuous TKI administration is the most promising strategy for a combination treatment in which the therapeutic benefit prevails adverse side effects. CONCLUSION: Our modelling approach is a highly beneficial tool to quantitatively address the competition between normal and leukaemic haematopoiesis in treated CML patients. We derive testable predictions for different experimental settings that are suggested before the clinical implementation of the combination treatment.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Hematopoietic Stem Cells/drug effects , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Models, Theoretical , Animals , Humans , Immunologic Factors/administration & dosage , Interferon-alpha/administration & dosage , Mice , Protein Kinase Inhibitors/administration & dosage
15.
Phys Chem Chem Phys ; 13(16): 7534-9, 2011 Apr 28.
Article in English | MEDLINE | ID: mdl-21431119

ABSTRACT

The electronic structure and magnetic properties of the graphene/Fe/Ni(111) system were investigated via combination of the density functional theory calculations and electron-spectroscopy methods. This system was prepared via intercalation of thin Fe layers (1 ML) underneath graphene on Ni(111) and its inert properties were verified by means of photoelectron spectroscopy. Intercalation of iron in the space between graphene and Ni(111) changes drastically the magnetic response from the graphene layer that is explained by the formation of the highly spin-polarized 3d(z(2)) quantum-well state in the thin iron layer.

16.
J Gen Psychol ; 137(4): 343-61, 2010.
Article in English | MEDLINE | ID: mdl-21086857

ABSTRACT

Previous studies have reported that our interpersonal knowledge shows an asymmetry; that is, we tend to believe that we know and understand other people's thoughts and feelings better than other people know and understand our own thoughts and feelings. In the present study, the authors compared American (114 men, 192 women) and Korean (99 men and 98 women) students to examine whether the asymmetry is greater in collectivistic than in individualistic culture in two types of relationships: horizontal (with best friends) and vertical (with parents). On all three items--Know, Understand, and Visibility--asymmetry was found for both horizontal and vertical relationships. Further, the Understand and Visibility items showed greater asymmetry for the Korean group than for the American group. It was concluded that asymmetry is greater in collectivistic than in individualistic culture. The cultural differences can be explained by self-consistency, sensitivity to social consequences, parent-child interaction, and living arrangement.


Subject(s)
Culture , Interpersonal Relations , Knowledge , Parent-Child Relations , Peer Group , Adult , Analysis of Variance , Cross-Cultural Comparison , Female , Humans , Male , Republic of Korea , United States
17.
J Phys Condens Matter ; 22(13): 135008, 2010 Apr 07.
Article in English | MEDLINE | ID: mdl-21389511

ABSTRACT

The substrate lattice structure may have a considerable influence on the formation of quantum well states in a metal overlayer material. Here we study three model systems using angle resolved photoemission and low energy electron diffraction: indium films on Si(111) and indium and lead on Si(100). Data are compared with theoretical predictions based on density functional theory. We find that the interaction between the substrate and the overlayer strongly influences the formation of quantum well states; indium layers only exhibit well defined quantum well states when the layer relaxes from an initial face-centred cubic to the bulk body-centred tetragonal lattice structure. For Pb layers on Si(100) a change in growth orientation inhibits the formation of quantum well states in films thicker than 2 ML.

19.
Phys Rev Lett ; 102(8): 086102, 2009 Feb 27.
Article in English | MEDLINE | ID: mdl-19257757

ABSTRACT

We have studied friction and dissipation in single and bilayer graphene films grown epitaxially on SiC. The friction on SiC is greatly reduced by a single layer of graphene and reduced by another factor of 2 on bilayer graphene. The friction contrast between single and bilayer graphene arises from a dramatic difference in electron-phonon coupling, which we discovered by means of angle-resolved photoemission spectroscopy. Bilayer graphene as a lubricant outperforms even graphite due to reduced adhesion.

20.
J Phys Condens Matter ; 21(40): 405005, 2009 Oct 07.
Article in English | MEDLINE | ID: mdl-21832407

ABSTRACT

Pseudomorphic growth of thin elemental metal films is often observed on a variety of crystalline solids. On quasicrystalline surfaces with their complex structure and the absence of translational periodicity, the situation is different since elemental metals do not exhibit quasicrystalline order, and hence the specific interaction between overlayer and substrate is decisive. Here we study the growth of manganese films on an icosahedral i-Al-Pd-Mn alloy with a view to establishing the growth mode and electronic structure. Although we observe an exponential intensity variation of the adlayer and substrate related x-ray photoemission spectroscopy (XPS) peaks, low energy electron diffraction (LEED) shows that Mn adlayers do not exhibit quasicrystallinity. The detailed structure of the Mn 2p core level line reveals considerable electronic structure differences between the quasicrystalline and elemental metal environment. Evidence of a substantial local magnetic moment on the Mn atoms in the overlayer (about 2.8  µ(B)) is obtained from the Mn 3s exchange splitting.

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