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1.
J Chem Phys ; 152(18): 184102, 2020 May 14.
Article in English | MEDLINE | ID: mdl-32414274

ABSTRACT

Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

2.
Int J Parasitol ; 38(1): 49-55, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17950292

ABSTRACT

Pseudophyllidea van Beneden in Carus, 1863, a well recognised order of tapeworms (Platyhelminthes: Eucestoda), is suppressed because it is composed of two phylogenetically unrelated groups, for which the new names Bothriocephalidea and Diphyllobothriidea are proposed. The new orders differ from each other in the following characters: (i) position of the genital pore: on the dorsal, dorso-lateral or lateral aspects and posterior to the ventral uterine pore in the Bothriocephalidea versus on the ventral aspect of segments and anterior to the uterine pore in the Diphyllobothriidea; (ii) the presence of a muscular external seminal vesicle in the Diphyllobothriidea, which is absent in the Bothriocephalidea; (iii) the presence of a uterine sac in the Bothriocephalidea, which is absent in the Diphyllobothriidea; and (iv) the spectrum of definitive hosts: mainly teleost fishes, never homoiothermic vertebrates in the Bothriocephalidea, versus tetrapods, most frequently mammals, in the Diphyllobothriidea, with species of Diphyllobothrium, Spirometra and Diplogonoporus parasitic in humans. The Diphyllobothriidea, which includes 17 genera in four families (Digramma is synonymised with Ligula), is associated with cestode groups that have a range of plesiomorphic characters (Haplobothriidea and Caryophyllidea), whereas the Bothriocephalidea, consisting of 41 genera grouped in four families, is the sister-group to the 'acetabulate' or 'tetrafossate' cestodes, which are generally regarded as having derived characters.


Subject(s)
Platyhelminths/classification , Animals , Bayes Theorem , Genes, Helminth , Phylogeny , Platyhelminths/genetics
3.
Int J Parasitol ; 36(14): 1535-41, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17010350

ABSTRACT

Phylogenetic relationships of cestodes of the order Pseudophyllidea (Platyhelminthes: Cestoda) were examined using sequences of complete small subunit and partial (D1-D3 region) large subunit nuclear rDNA of members of all pseudophyllidean families. The results provide evidence of paraphyly of the order as indicated by previous molecular phylogenetic analyses based on a much lower number of species sequenced. Pseudophyllidean tapeworms represent an artificial assemblage comprising two unrelated clades. "Bothriocephalidea" is formed by four families sensu Bray et al. (1994), namely Bothriocephalidae, Echinophallidae, Philobythiidae and Triaenophoridae, whereas two other families, Diphyllobothriidae and Cephalochlamydidae, give rise to the "Diphyllobothriidea". The present results indicate that "Bothriocephalidea" forms the most derived clade of all difossate and tetrafossate/bothriate tapeworm lineages which are considered to be basal relative to the rest of tetrafossate/bothridiate and acetabulate cestodes. By contrast, "Diphyllobothriidea", which includes medically important parasites (Diphyllobothrium and Spirometra), appeared more basal, without a clearly resolved position within other difossate tapeworm lineages.


Subject(s)
Cestoda/genetics , Phylogeny , RNA, Helminth/genetics , RNA, Ribosomal/genetics , Animals , Base Sequence , Cestoda/classification , DNA, Helminth/genetics , DNA, Ribosomal/genetics , Diphyllobothrium/classification , Diphyllobothrium/genetics , Molecular Sequence Data , Sequence Analysis, DNA/methods
4.
Acta Neurol Scand ; 113(1): 40-5, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16367898

ABSTRACT

OBJECTIVES: We measured the volumes of the amygdala to test the hypothesis that the reduction of amygdalar volume may be associated with psychiatric symptoms in Alzheimer's disease. MATERIALS AND METHODS: Twenty-seven patients underwent neuropsychological investigation including the assessment of general clinical severity by the Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory (NPI). All patients underwent magnetic resonance imaging (MRI) of the head, from which the volumes of the amygdalae were measured. The obtained values were compared with those of controls (n = 15). RESULTS: Patients with Alzheimer's dementia showed significant reduction in MRI volumetric measurements compared with controls. We found a significant correlation of MMSE score and absolute amygdala volume (r = 0.62, P < 0.01). Neither the absolute nor relative volume of the amygdala showed any correlation with NPI scores. CONCLUSIONS: The atrophy of the amygdala does not have a direct association with the existence of neuropsychiatric symptoms. MRI volumetry of the amygdala may be relevant as a marker of dementia severity in Alzheimer's disease.


Subject(s)
Alzheimer Disease/pathology , Amygdala/pathology , Magnetic Resonance Imaging , Mental Disorders/pathology , Aged , Aged, 80 and over , Alzheimer Disease/complications , Alzheimer Disease/psychology , Atrophy , Cross-Sectional Studies , Female , Humans , Male , Mental Disorders/etiology , Mental Status Schedule , Middle Aged , Neuropsychological Tests , Severity of Illness Index
5.
Sb Lek ; 104(1): 13-65, 2003.
Article in English | MEDLINE | ID: mdl-14577136

ABSTRACT

BACKGROUND: For comparing of the pathological and normal healthy state it is essential to obtain sufficient amount of the volumetric data. Nevertheless most of the publicized works use only few healthy controls opposite to the patients for the measuring of the basal ganglia volume. Further essential condition is to take into account the effect of age to the basal ganglia volume in such analysis. PURPOSE: The goal of our study was (1) to give the current review of the structure, neurotransmitters, connections and general integration of the basal ganglia in the pathways of the central nervous system, (2) aggregate sufficient amount of volumetric data by virtue of MRI and post-mortem studies, and appoint volumes of the striatum and pallidum, (3) evaluate aging of these structures in adult healthy patients. Another goal was (4) to inspect the correlations between the size of the basal ganglia and volume characteristics of the brain, cranial capacity or frequently measured dimensions within CNS. In the spite of the fact that it is not possible to measure all of these dimensions for clinicians who want to determine if the structure is "normal" or not. Another goal was (5) to find a simple measure, which could serve as the indicator of the real size of structure of the interest. METHODS: By virtue of the classical anatomical methods and MRI examination we appointed volumes of the striatum (furthermore divided into the complex of the caudatum--nucleus accumbens--CD-Acc and putamen) and pallidum in the sample of 108 healthy adults (18-89 years old). From another measurements we calculated the cranial capacity and volume characteristics of each brain. RESULTS: In a general view that does not respect changes due to age neither volumetric difference between two sexes nor interhemispheric difference was significant for absolute volumes of the striatum, CD-Acc complex, putamen and pallidum. In the case of the striatum, significant correlation between size and age was found (p < 0.0001) for absolute volumes in both sexes. In men, striatum showed a decrease about 14.3% in volume in the 20-50-year age range (about 4.8% per decade). In woman, the age related shrinkage is about 16.9% (about 5.6% per decade). Dependence on age was not statistically proven for volume of female complex CD-Acc (p = 0.061). Age related decrease of female putamen was about 23.15% in the 20-50 year age range (7.7% per decade). In men, the seizure decrease of the caudate--accumbens complex amounts 16.2%, in the same age range (5.4% per decade). Similarly, volume of the putamen in men decreases up to 12.3% between 20-50 years of age (4.1% per decade). In men, the pallidum showed a decrease about 21.6% in volume in the 20-50-year age range (7.2% per decade). In women, it amounts only 11.5% (3.8% per decade). Plane of the striatum in the level of the commissura anterior showed high correlation with total striatal volume (p < 0.0001, r = 0.668). The percentual portion of striatal volume at the level of the commissura anterior (1 cm thick slice) does not differ statistically between males and females. In our data it gives 28.56% (SD = 3.05). Correlation between the striatal planes and age was significant in both sexes (in women: p = 0.007, r = 0.348, and in men: p = 0.029, r = 0.349) as in the case of the correlation between striatal volume and age. CONCLUSIONS: Our findings suggest that age mirror differently on separate structures in the brain. We have found unequal volume decrease within both sexes even particular nuclei. Our findings also suggest that decrease of the basal ganglia volume in the dependence on age is not linear but it is composed from periods without changes and periods with reduction of its size. In the case of the striatum, behaviour of changes looks similar (with only 5 years), while in the case of the pallidum this situation is markedly different. Our observations may suggest intersexual singularity in the aging of brain structures. From one MRI, from one frontal slice in the level of the commissura anterior is possible to reduce total volume of the striatum for every examined individual. Simple graph shows interval, where the normal value of this plain should be in dependency on age and sex of the examined patient. Another graph allows reducing from this plane the total volume of the striatum. These findings can be the quick and reliable aid in better diagnostics of different diseases.


Subject(s)
Aging/pathology , Corpus Striatum/anatomy & histology , Adult , Aged , Aged, 80 and over , Corpus Striatum/cytology , Female , Globus Pallidus/anatomy & histology , Globus Pallidus/cytology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neural Pathways/anatomy & histology , Reference Values
6.
P N G Med J ; 28(4): 251-6, 1985 Dec.
Article in English | MEDLINE | ID: mdl-3869758

ABSTRACT

Many rural health centres in developing countries continue to treat patients without the help of any laboratory tests. The result is often inaccurate diagnosis, wasteful use of multiple drugs, and increasing drug resistance of pathogens. It is unlikely that there will ever be sufficient funds to employ a full-time laboratory worker at each of the many small remote health centres in Papua New Guinea. It is also doubtful whether staff and health extension officers who run such centres have the appropriate knowledge to adequately utilize full-time laboratory personnel. It is feasible, however, to train selected health workers in courses of three to four months' duration to perform a few simple laboratory tests part-time, in addition to their clinical duties. Suitable tests are those where the result does not require skilled interpretation. For most such tests, the result is the diagnosis. After the clinical staff have received the laboratory diagnosis, they are free to decide whether it fits the clinical picture. If so, they can then find the appropriate treatment to prescribe in standard treatment books. The present paper describes the experience in setting up and operating laboratory training for health centre staff in Milne Bay Province, Papua New Guinea. Costs and initial results of the program are discussed.


Subject(s)
Allied Health Personnel/education , Community Health Centers , Laboratories , Rural Health , Allied Health Personnel/economics , Curriculum , Humans , Papua New Guinea , Workforce
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