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1.
Acta Cardiol ; 78(7): 828-837, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37694719

ABSTRACT

OBJECTIVES: Acute heart failure (AHF) hospitalisation is associated with 10% mortality. Outpatient based management (OPM) of AHF appeared effective in observational studies. We conducted a pilot randomised controlled trial (RCT) comparing OPM with standard inpatient care (IPM). METHODS: We randomised patients with AHF, considered to need IV diuretic treatment for ≥2 days, to IPM or OPM. We recorded all-cause mortality, and the number of days alive and out-of-hospital (DAOH). Quality of life, mental well-being and Hope scores were assessed. Mean NHS cost savings and 95% central range (CR) were calculated from bootstrap analysis. Follow-up: 60 days. RESULTS: Eleven patients were randomised to IPM and 13 to OPM. There was no statistically significant difference in all-cause mortality during the index episode (1/11 vs 0/13) and up to 60 days follow-up (2/11 vs 2/13) [p = .86]. The OPM group accrued more DAOH {47 [36,51] vs 59 [41,60], p = .13}. Two patients randomised to IPM (vs 6 OPM) were readmitted [p = .31]. Hope scores increased more with OPM within 30 days but dropped to lower levels than IPM by 60 days. More out-patients had increased total well-being scores by 60 days (p = .04). OPM was associated with mean cost savings of £2658 (95% CR 460-4857) per patient. CONCLUSIONS: Patients with acute HF randomised to OPM accrued more days alive out of hospital (albeit not statistically significantly in this small pilot study). OPM is favoured by patients and carers and is associated with improved mental well-being and cost savings.


Subject(s)
Heart Failure , Outpatients , Humans , Pilot Projects , Cost Savings , Heart Failure/therapy , Hospitalization
2.
Proc Biol Sci ; 290(1991): 20221496, 2023 01 25.
Article in English | MEDLINE | ID: mdl-36651050

ABSTRACT

Attentional set shifting is a core ingredient of cognition, allowing for fast adaptation to changes in the environment. How this skill compares between humans and other primates is not well known. We examined performance of 3- to 5-year-old children and chimpanzees on a new attentional set shifting task. We presented participants with two shelves holding the same set of four boxes. To choose the correct box on each shelf, one has to switch attention depending on which shelf one is currently presented with. Experiment 1 (forty-six 3- to 5-year olds, predominantly European White) established content validity, showing that the majority of errors were specific switching mistakes indicating failure to shift attention. Experiment 2 (one hundred and seventy-eight 3- to 6-year olds, predominantly European White) showed that older children made fewer mistakes, but if mistakes were made, a larger proportion were switching mistakes rather than 'random' errors. Experiment 3 (52 chimpanzees) established suitability of the task for non-human great apes and showed that chimpanzees' performance was comparable to the performance of 3- and 4-year olds, but worse than 5-year olds. These results suggest that chimpanzees and young children share attentional set shifting capacities, but that there are unique changes in the human lineage from 5 years of age.


Subject(s)
Attention , Pan troglodytes , Animals , Humans , Child, Preschool , Child , Adolescent , Cognition , Reversal Learning
3.
Phys Rev Lett ; 115(8): 087801, 2015 Aug 21.
Article in English | MEDLINE | ID: mdl-26340209

ABSTRACT

We report on the first direct nanoscale imaging of elementary edge dislocations in a thermotropic smectic-C* liquid crystal with the Burgers vector equal to one smectic layer spacing d. We find two different types of dislocation profiles. In the dislocation of type A, the layers deformations lack mirror symmetry with respect to the plane perpendicular to the Burgers vector; the dislocation core size is on the order of d. In the dislocation of type S, the core is strongly anisotropic, extending along the Burgers vector over distances much larger (by a factor of 4) than d. The difference is attributed to a different orientation of the molecular tilt plane with respect to the dislocation's axis; the asymmetric layers distortions are observed when the molecular tilt plane is perpendicular to the axis and the split S core is observed when the molecules are tilted along the line.

4.
Philos Trans R Soc Lond B Biol Sci ; 368(1630): 20130050, 2013 Nov 19.
Article in English | MEDLINE | ID: mdl-24101632

ABSTRACT

Many species use tools, but the mechanisms underpinning the behaviour differ between species and even among individuals within species, depending on the variants performed. When considering tool use 'as adaptation', an important first step is to understand the contribution made by fixed phenotypes as compared to flexible mechanisms, for instance learning. Social learning of tool use is sometimes inferred based on variation between populations of the same species but this approach is questionable. Specifically, alternative explanations cannot be ruled out because population differences are also driven by genetic and/or environmental factors. To better understand the mechanisms underlying routine but non-universal (i.e. habitual) tool use, we suggest focusing on the ontogeny of tool use and individual variation within populations. For example, if tool-using competence emerges late during ontogeny and improves with practice or varies with exposure to social cues, then a role for learning can be inferred. Experimental studies help identify the cognitive and developmental mechanisms used when tools are used to solve problems. The mechanisms underlying the route to tool-use acquisition have important consequences for our understanding of the accumulation in technological skill complexity over the life course of an individual, across generations and over evolutionary time.


Subject(s)
Adaptation, Physiological , Learning , Tool Use Behavior , Animals , Humans , Phenotype
5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(5 Pt 1): 051706, 2007 May.
Article in English | MEDLINE | ID: mdl-17677083

ABSTRACT

Previous results from Kundu using dielectric relaxation have suggested a reentrant antiferroelectric-ferroelectric-antiferroelectric transition in the compound LN36. Our comprehensive studies of this compound using differential optical reflectivity, nonadiabatic scanning calorimetry, null transmission ellipsometry, and resonant x-ray diffraction show that in fact LN36 exhibits the usual phase sequence for chiral smectic liquid crystals: SmA*-SmC*alpha-SmC*-SmC*FI1-SmC*A . Moreover, the SmC*alpha-SmC* transition is a first-order transition, characterized by a discontinuous change in the helical pitch. At temperatures just above the SmC*alpha-SmC* transition, two different values for the helical pitch are simultaneously observed for the first time.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(4 Pt 1): 041704, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12786374

ABSTRACT

The temperature and frequency dependent dielectric relaxation behavior of a liquid crystalline (S)-(+)-1-methylheptyl 4-[2-(4-alkoxyphenyl) thiophene-5-carbonylthiooxy] benzoate system is reported. Interesting successive antiferroelectric-ferroelectric-antiferroelectric (AF-FE-AF) phase transitions are observed in this system resembling the successive phase transitions observed in crystalline Rochelle salt. The smectic-C* (SmC*) to AF1 phase transition (around 103.0 degrees C) is first order in nature, predicted from the use of Orihara and Ishibashi theory. It is also found that a contribution of the ferroelectric SmC* phase ordering penetrates even in the antiferroelectric AF1 (SmC(*)(A)) and AF2 (SmC(*)(A)) phases very close to the SmC*-AF1 and SmC*-AF2 phase boundaries (critical regions). It is suggested that this type of mixing of AF and FE phases might cause surface induced ferroelectric- or ferroelectric-type ordering near the AF-FE phase transitions. A soft mode with Debye-type dispersion was observed in the SmA phase. The thermal behaviors of dielectric dispersion, absorption, and dielectric strength in different phases are also reported and discussed.

8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(4 Pt 1): 041705, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12005844

ABSTRACT

The structures of the liquid crystalline chiral subphases exhibited by several materials containing either a selenium or sulphur atom have been investigated using a resonant x-ray scattering technique. This technique provides a unique structural probe for the ferroelectric, ferrielectric, antiferroelectric, and SmC(*)(alpha) phases. An analysis of the scattering features allows the structural models of the different subphases to be distinguished, in addition to providing a measurement of the helical pitch. This paper reports resonant scattering features in the antiferroelectric hexatic phase, the three- and four-layer intermediate phases, the antiferroelectric and ferroelectric phases and the SmC(*)(alpha) phase. The helicoidal pitch has been measured from the scattering peaks in the four-layer intermediate phase as well as in the antiferroelectric and ferroelectric phases. In the SmC(*)(alpha) phase, an investigation into the helical structure has revealed a pitch ranging from 5 to 54 layers in different materials. Further, a strong resonant scattering signal has been observed in mixtures of a selenium containing material with as much as 90% nonresonant material.

10.
J Org Chem ; 66(22): 7283-6, 2001 Nov 02.
Article in English | MEDLINE | ID: mdl-11681939

ABSTRACT

A variety of alkoxythiophenes have been synthesized that represent ideal subunits for the synthesis of a new class of thermotropic liquid crystals via palladium-catalyzed cross-coupling reactions and organometallic derivatization. The methodology used represents the first highly efficient synthesis of alkoxythiophenes unlike previous pathways that have presented serious synthetic difficulties when the alkoxy chain consisted of more than four carbon atoms. The scope of the new procedure (relative to liquid crystalline intermediates) is presented and is compared and contrasted with the current literature.

11.
Heart Fail Rev ; 6(4): 317-23, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11447306

ABSTRACT

Both ET(A) selective and dual, ET(A/B), receptor antagonists have favourable short- and longer-term haemodynamic actions in patients with acute and chronic heart failure. Their effect on neurohumoral measures is not yet fully determined. Two moderately large, medium-duration studies have examined the effect of dual ET(A/B) receptor antagonists on clinical status, reaching conflicting conclusions. One large scale, long-term, morbidity mortality evaluation is underway with bosentan.


Subject(s)
Endothelin Receptor Antagonists , Heart Failure/drug therapy , Chronic Disease , Clinical Trials as Topic , Endothelin-1/physiology , Heart Failure/physiopathology , Hemodynamics/drug effects , Hemodynamics/physiology , Humans , Middle Aged , Receptors, Endothelin/physiology
13.
Article in English | MEDLINE | ID: mdl-11970599

ABSTRACT

We report polarization-analyzed, resonant x-ray diffraction at the sulfur K edge performed upon free-standing liquid-crystal films. Our studies of the thiobenzoate liquid-crystal enantiomer 10OTBBB1M7 yield the polarization states of resonant satellite peaks arising from characteristic superlattices in the chiral smectic-C (SmC(*)) variant phases, including the antiferroelectric SmC(*)(A), ferrielectric SmC(*)(FI1) and SmC(*)(FI2), as well as SmC(*)(alpha). The observed polarizations agree with the clock model of chiral smectic-C variants, and rule out other proposals made to date for these structures. Data from the 10OTBBB1M7 racemate also support the clock model. Our resonant diffraction results from a thiophene liquid-crystal compound reveal the same superlattice periodicities seen in corresponding antiferroelectric and ferrielectric phases of 10OTBBB1M7.

14.
J Phys Condens Matter ; 8(38): L551-6, 1996 Sep 16.
Article in English | MEDLINE | ID: mdl-22146515

ABSTRACT

The effects of temperature and applied voltage on the pyroelectric properties of an antiferroelectric liquid crystal are given. It has been found that the pyroelectric signal depends strongly on the bias voltage across the sample. The pyroelectric signal behaviour is interpreted with the aid of spontaneous polarization data and good agreement is found between the results from the pyroelectric and polarization techniques. The spontaneous polarization of the sample exhibits the temperature- and field-induced `Devil's staircase' behaviour, as predicted by the Ising model.

15.
J Adv Nurs ; 21(6): 1136-43, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7665779

ABSTRACT

Boundaries exist that dictate socially acceptable degrees of bodily exposure and touch. Certain groups, for example nurses, appear to undertake emotionally charged work where they are called upon to cross these boundaries. This paper relates the experience of a student nurse cohort as they 'crossed the boundaries'. The students' views were collected by participant observation and interview, and analysed by employing grounded theory. Since the study was longitudinal the findings reflect how the neophytes' views changed with the passage of time. Early in their course students found giving intimate care stressful, while caring for those of the opposite sex created particular difficulties. Both male and female students developed coping strategies, for example 'ways of seeing' those they nursed. Students maintained that the nature of their work led others to view them in certain ways. In some instances female students might be seen as sexually available by men for whom they cared; however, with experience they dealt effectively with sexual advances. The cohort considered that wearing a uniform on the one hand protected and legitimized them in crossing boundaries, but on the other it signalled their occupation to others which on occasions was something they might wish to conceal. These findings provide insights into the notion of crossing social boundaries, an area which warrants further investigation, since it involves an important aspect of caring. (Names of students cited in this paper are pseudonyms.)


Subject(s)
Clinical Nursing Research , Nurse-Patient Relations , Psychological Distance , Social Behavior , Students, Nursing/psychology , Adaptation, Psychological , Clothing , Female , Gender Identity , Humans , Longitudinal Studies , Male , Role , Sexual Harassment , Wit and Humor as Topic
16.
J Adv Nurs ; 21(5): 845-52, 1995 May.
Article in English | MEDLINE | ID: mdl-7601991

ABSTRACT

Sanitized accounts of research add little to the literature describing 'how' research is actually 'done'. This paper explores issues which emerged during the course of a longitudinal study which described the experiences of a cohort of 23 student nurses during their 3-year training for registration as general nurses in the United Kingdom. The approach used was that of grounded theory. The students' changing perspectives were collected by the researcher utilizing participant observation and unstructured interview in various clinical settings. In recognition of the fact that this is a 'reflexive' account it is written in the first person. Issues addressed include my 'immersion' in the research process, my relationship with the students, the challenges which derive from researching in a shifting context and the use of grounded theory within the context of the study. (All the names of students involved in the study are pseudonyms.)


Subject(s)
Nursing Research/methods , Ethics, Nursing , Humans , Interprofessional Relations , Longitudinal Studies , Nursing Theory , Students, Nursing , United Kingdom
17.
J Adv Nurs ; 19(4): 738-48, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8021396

ABSTRACT

The ideas discussed in this paper are derived from a longitudinal study of student nurse socialization. The emergent views of a cohort of student nurses were explored by the researcher, over a period of 3 years, utilizing the approach referred to as grounded theory. 'Patients to people' represents a continuum of changing perceptions about those whom the students were nursing. It seemed that the cohort had to move along this continuum in order for them to be able to empathize with those they nursed. In the context of the students' changing perceptions, several things were of significance. For example, encounters with individuals who failed to demonstrate the passive and compliant attitude associated with 'typical patients', such as children, challenged the cohort's thinking about those they nursed. During their training the students matured as both nurses and adults and this was also important, as was their recognition of their own 'personhood'. The cohort's emergent views suggested that there was a reciprocity between the way they viewed themselves and the perceptions they held about those they nursed. Such findings are important to people involved in preparing individuals to enter the caring professions. However, it should be noted that the experiences described in this study represent those of 'traditionally' trained rather than of Project 2000 students. The names used to describe people involved in this research are pseudonyms.


Subject(s)
Attitude of Health Personnel , Empathy , Nurse-Patient Relations , Socialization , Students, Nursing/psychology , Education, Nursing , Female , Humans , Longitudinal Studies , Male , Nursing Methodology Research , Self Concept
18.
Environ Monit Assess ; 13(1): 1-9, 1989 Aug.
Article in English | MEDLINE | ID: mdl-24243106

ABSTRACT

Fixed station sampling is the conventional method used to obtain data on the median water quality of reservoirs. A major source of uncertainty associated with this technique is that water quality at the fixed stations may not be representative of the ambient water quality in the reservoir at the time of sampling. This problem is particularly relevant for water quality variables such as chlorophyll, which have a markedly patchy spatial distribution. The use of Landsat reflectance data to estimate median chlorophyll concentrations in Roodeplaat Dam was investigated. A linear polynomial regression model for estimating chlorophyll concentrations from Landsat reflectance data, was firstly calibrated with chlorophyll concentration data obtained by sampling seven fixed stations on the reservoir at the time of the satellite overflight to produce an individual calibration. Secondly, the model was calibrated with a pooled set of sampled data obtained from five separate overflights, to obtain a generalised calibration.It was found that median chlorophyll concentrations determined from Landsat-derived data were similar to median chlorophyll concentrations estimated from fixed station data. However, the range of chlorophyll concentrations in the reservoir estimated from Landsat data was considerably larger than that estimated from fixed station data. Landsat derived estimates of chlorophyll concentrations have the added advantage of providing information on the spatial distribution of chlorophyll in the reservoir.

19.
Ann Trop Paediatr ; 6(2): 155-6, 1986 Jun.
Article in English | MEDLINE | ID: mdl-2425726

ABSTRACT

Stool samples from 83 Sudanese children with gastro-enteritis were examined using a safranin-methylene blue stain. Five children (6.1%) were excreting cryptosporidium oocysts but no other potential enteropathogens. The clinical features of anorexia, vomiting and pyrexia and the profuse green watery offensive stool were similar to those reported previously. All of the children were dehydrated. None of 37 children studied who did not have gastro-enteritis was excreting oocysts.


Subject(s)
Cryptosporidiosis , Gastroenteritis/etiology , Child, Preschool , Cryptosporidiosis/parasitology , Cryptosporidium/isolation & purification , Feces/parasitology , Female , Gastroenteritis/parasitology , Humans , Infant , Male , Sudan
20.
Scand J Haematol ; 34(5): 401-5, 1985 May.
Article in English | MEDLINE | ID: mdl-2990022

ABSTRACT

Combined deficiency of factor V and factor VIII, a rare bleeding disorder, is reported in a Syrian family. 2 siblings, 10 and 6 yr old are affected. They had mild bleeding manifestations. Their prothrombin time and partial thromboplastin time were prolonged, but thrombin time was normal. Both had low levels of factor V, (6% and 7%), factor VIII, (both 10%) factor VCAg (both 6%) and factor VIII CAg, (6% and 4%). All members of this family had normal levels of factor VIIIR:Ag, protein C, antigen and protein C inhibitor. The normal levels of protein C and protein C inhibitor in the 2 affected family members indicate that the combined deficiency of factors V and VIII has nothing to do with protein C. This contrasts with previous reports that deficiency of protein C inhibitor is the cause of combined factor V and factor VIII deficiency. The probable mode of inheritance of this defect is discussed.


Subject(s)
Blood Coagulation Factors/analysis , Blood Proteins/analysis , Factor V Deficiency/blood , Glycoproteins/analysis , Hemophilia A/blood , Blood Coagulation Tests , Child , Factor V Deficiency/complications , Factor V Deficiency/genetics , Female , Hemophilia A/complications , Hemophilia A/genetics , Humans , Male , Pedigree , Protein C , Protein C Inhibitor , Reference Values
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