bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characteristic fragmentation behavior of some glucuronide‐type triterpenoid saponins using electrospray ionization tandem mass spectrometry
Authors: Li Bin , Abliz Zeper , Fu Guangmiao , Tang Meijun , Yu Shishan 
Published: January 2005

AbstractThe fragmentation behavior of some glucuronide‐type triterpenoid saponins from Symplocos chinensis, and their analogues escin Ia and Ib, were investigated by positive ion electrospray ionization tandem mass spectrometry using a quadrupole linear ion trap mass spectrometer. The fragmentation patterns of these saponins significantly changed in accordance with structural variations in the glucuronyl residue of the oligosaccharide chain. It was found that the carboxyl group and hydroxyl group at the C‐3′ position of the glucuronyl residue were the key sites for determining the fragmentation behavior of these compounds. When the carboxyl group was esterified, only the C2α ion, and no B2α ion, and cationized aglycone were observed. When the hydroxyl group at C‐3′ was acylated, the inherent cross‐ring cleavage was hindered. However, glycosidic cleavages always occurred, regardless of the crucial structural variations. The results of the present studies can benefit the determination of trace triterpenoid saponins of this type in crude plant extracts, and also provide background information to aid the structural investigations of similar glycoconjugates. Copyright © 2005 John Wiley & Sons, Ltd.
Divergence between community psychologists in academic and nonacademic settings: A closer look at the implications
Authors: Elias Maurice J. , Dalton James H. , Franco Robert , Howe George W. 
Published: January 2005

ConclusionThe ecological principle of interdependence has been a guiding theme in our research and conceptualization. For the development of community psychology, academic and applied interest and networks must be integrated in ways which value the views and resources of both groups. This is the focus of Kelly's (1984) remarks. The dynamic interplay of ideas, data, and practices is likely to facilitate the collaboration between researchers and setting inhabitants which Trickett (1984) describes as the distinctive quality of community psychology. Common pathways of information exchange, joint responsibility for training future members of the field, and mutually enhancing role relationships are needed. Current channels of communication provide little ease of access or incentives for participation by psychologists in nonacademic settings. It thus becomes the reponsibility of all concerned community psychologists to use their organizational skills to redress this harmful imbalance (Kelly, 1984). For this to occur, however, we must take the initial steps of frankly recognizing differences in our folkways and organizational constraints, while also emphasizing our common values and assets. The largest threat to the field is external constraints from university and clinical service settings on the work that represents community psychology (Elias et al., 1984). If we are dividedor uninformed in the face of these environmental presses, we will never create the adaptive niche that community psychology needs to survive.
A computer checked algebraic verification of a distributed summation algorithm
Authors: Groote Jan Friso , Monin François , Springintveld Jan 
Published: January 2005

Abstract.
We present an algebraic verification of Segall’s propagation of information with feedback algorithm and we report on the verification of the proof using the PVS system. This algorithm serves as a nice benchmark for verification exercises (see [2, 8, 17]). The verification is based on the methodology presented in [7] and demonstrates its suitability to deliver mechanically verifiable correctness proofs of highly nondeterministic distributed algorithms.
Active galaxies and radiative heating
Authors: Ostriker Jeremiah P. , Ciotti Luca 
Published: January 2005

There is abundant evidence that heating processes in the central regions of elliptical galaxies have both prevented large–scale cooling flows and assisted in the expulsion of metal rich gas. We now know that each such spheroidal system harbours in its core a massive black hole weighing ca. 0.13% of the mass in stars and also know that energy was emitted by each of these black holes with an efficiency exceeding 10% of its rest mass. Since, if only 0.5% of that radiant energy were intercepted by the ambient gas, its thermal state would be drastically altered, it is worth examining in detail the interaction between the out–flowing radiation and the equilibrium or inflowing gas. On the basis of detailed hydrodynamic computations we find that relaxation oscillations are to be expected with the radiative feedback quite capable of regulating both the growth of the central black hole and also the density and thermal state of the gas in the galaxy. Mechanical input of energy by jets may assist or dominate over these radiative effects.We propose specific observational tests to identify systems which have experienced strong bursts of radiative heating from their central black holes.
Statistical characterization of TEM images of silica‐filled rubber
Authors: TSCHESCHEL A. , LACAYO J. , STOYAN D. 
Published: January 2005

SummaryTransmission electron microscopy is used to study the micro‐dispersion of silica fillers within the polymer matrix of rubber. The resulting grey‐value images are interpreted as realizations of random fields and are characterized by means of variograms. The so‐called Cauchy class is a suitable model for this purpose. Statistical analysis shows that different filler dispersion properties are reflected in different variogram parameters. As a case study, the random field approach is demonstrated for four exemplary rubber compounds.
Combined AFM and confocal fluorescence microscope for applications in bio‐nanotechnology
Authors: KASSIES R. , VAN DER WERF K. O. , LENFERINK A. , HUNTER C. N. , OLSEN J. D. , SUBRAMANIAM V. , OTTO C. 
Published: January 2005

SummaryWe present a custom‐designed atomic force fluorescence microscope (AFFM), which can perform simultaneous optical and topographic measurements with single molecule sensitivity throughout the whole visible to near‐infrared spectral region. Integration of atomic force microscopy (AFM) and confocal fluorescence microscopy combines the high‐resolution topographical imaging of AFM with the reliable (bio)‐chemical identification capability of optical methods. The AFFM is equipped with a spectrograph enabling combined topographic and fluorescence spectral imaging, which significantly enhances discrimination of spectroscopically distinct objects. The modular design allows easy switching between different modes of operation such as tip‐scanning, sample‐scanning or mechanical manipulation, all of which are combined with synchronous optical detection. We demonstrate that coupling the AFM with the fluorescence microscope does not compromise its ability to image with a high spatial resolution. Examples of several modes of operation of the AFFM are shown using two‐dimensional crystals and membranes containing light‐harvesting complexes from the photosynthetic bacterium Rhodobacter sphaeroides.
Shape discrimination by total curvature, with a view to cancer diagnostics
Authors: GARDNER R. J. , HOBOLTH A. , JENSEN E. B. V. , SØRENSEN F. B. 
Published: January 2005

SummaryThis paper investigates the use of total curvature for shape discrimination of objects via profiles of their planar sections (not assumed to be star shaped). Methods of estimating total curvature from observation of a finite number of points on the boundary of the object are investigated, including a simple discrete approximation method and various interpolation methods. Total curvature is capable of revealing shape differences on a local scale, as demonstrated by the analysis of two data sets of malignant and normal or benign tumour cell nuclear profiles.
Single‐particle visualization of assembly: I. Dimerization in a planar zone
Authors: WANG H. , WU I. , YANG Q. , CATALANO C. E. , SERWER P. 
Published: January 2005

SummarySingle‐particle fluorescence microscopy of association/dissociation is required for analysis of biological assembly reactions. Toward achieving this goal, Wang et al. (J. Microsc., 2004, 213, 101–109) used molten agarose to concentrate thermally diffusing particles in a thin zone of solution next to the surface of a coverglass (plane of concentration). The present study details the first real‐time, single‐particle analysis of the association/dissociation of thermally diffusing particles in the plane of concentration. The test particles were procapsids of bacteriophage λ (radius = 31 nm). Quantification of thermal motion was developed and used to determine whether co‐diffusing particles were bound to each other. The data are explained by (1) the presence of a molten agarose‐generated barrier that is 93–155 nm from the coverglass surface, and (2) non‐random orientation of procapsid dimers in the plane of concentration.
Evaluation of syphilis in patients with HIV infection in Nigeria
Authors: Nnoruka E. N. , Ezeoke A. C. J. 
Published: January 2005

SummaryObjective  To document the manifestations of syphilis among patients with concurrent HIV infection over a 12‐month period.Method  Descriptive, cross‐sectional, hospital‐based study of all adult patients with syphilis and HIV infection who attended the skin clinic of the University of Nigeria, Teaching Hospital, Enugu, between July 2000 and June 2001. A standardized questionnaire was used to record age, sex, marital status, occupation and risk factor for HIV infection; initial site of onset of rash/ulcers, duration of the illness, any concomitant affection of mucosa, hair and nails as well as treatments received by each patient prior to presentation. Morphological distribution of lesions, mucosal surface (conjuctival, vulval and rectal) examinations and documentation of concomitant disorders with HIV were noted by the examining dermatologist. Lesional biopsy and dark‐field microscopy were undertaken to confirm diagnosis where serologic (non‐treponemal and treponemal specific) tests for syphilis were inconsistent with clinical suspicion. Each patient had a routine chest x‐ray, mantoux and purified protein derivative (PPD) status taken.Results  Thirty‐one patients (21 males) with concurrent syphilis and HIV were seen during the study period. Primary syphilis was diagnosed in nine (29%), secondary syphilis in 20 (64.5%) and latent syphilis in two (6.5%). Neurosyphilis was not observed. Prevalence of syphilis for these patients with concurrent HIV was 2.1%. Mean duration of syphilis was 3.9 months ± 1.4 and lesions of greatest concern occurred mainly on the genitalia. The glans penis was affected in 10 (32.3%) cases, the penile shaft in seven (22.6%), the oral cavity in five (16.1%), the rectum in six (19.4%) and the vulva in three (0.9%) cases. Nine (29.1%) patients had a history of primary syphilitic chancre, 19 (61.3%) had a past history of sexually transmitted disease (STD) – particularly genital ulcers – while three (9.7%) could not recall any past history of STD. Eighteen (59.3%) had a history of unprotected sex, 16 (51.7%) had multiple sexual partners, four (13.3%) had had oral sex, and one anal sex (3.3%); none admitted to being bisexual. Other relevant risk factors for HIV transmission were blood transfusion within 5 years for three (9.7%) and intravenous drug use in two (6.5%). Some patients had more than one condition as a potential source of exposure. Serological tests were weakly reactive in 17 (48.4%), strongly reactive in nine (29%) and non‐reactive in five (16.1%) patients. Three patients exhibited prozone phenomenon. Treatment comprised the syndromic approach, which currently is advocated for use in primary healthcare centres without facilities for aetiological diagnosis of sexually transmitted infections.Conclusion  Our cases with concurrent syphilis and HIV/AIDS had unusual manifestations, responded to treatment more slowly and died sooner than cases described in Western literature due to generally lower levels of health.
Temporal relationship between the occurrence of fresh noma and the timing of linear growth retardation in Nigerian children
Authors: Enwonwu Cyril O. , Phillips Reshma S. , Ferrell Christine D. 
Published: January 2005

SummaryBackground  Fresh noma (cancrum oris) occurs predominantly in children <4 years of age. The key risk factors are poverty, malnutrition and infections. Evolution from an intraoral inflammation to a grotesque oro‐facial gangrene is very rapid.Objective  We assessed potential relationship between the occurrence of fresh noma and linear growth retardation (LGR) which is prevalent in deprived Third World infants/children between ages 3 and 30 months. LGR is attributed to malnutrition and chronic immunostimulation by environmental antigens.Design  Anthropometric evaluation of children (n = 91) with fresh noma, ages 0–8 years, in relation to US National Center for Health Statistics Reference values was carried out. Age‐matched noma‐free, poor village children (n = 151) from similar communities as noma cases, and elite urban children (n = 132) served as control groups. Heights and weights were measured and the height for age (HAZ), weight for age (WAZ) and weight for height (WHZ) scores calculated as indices of stunting, underweight and wasting respectively. Serum level of interleukin (IL)‐18, a multifunctional cytokine, was also measured.Results  In the age groups 0–4 and 4–8 years, the percentages of noma children <−2.0SD were 91% and 67% respectively. The corresponding values for the village children were 37% and 24% and significantly different (P < 0.001) from the noma group. Only 7% of the elite children aged 4–8 years were stunted. Low body weight and wasting were prominent features of village and noma groups, but more marked in the latter. Associated with noma was a profound increase (P < 0.001) in IL‐18 in comparison with urban controls, and a 34% non‐statistically significant increase relative to the village control group. Among other functions, IL‐18 induces several pro‐inflammatory cytokines and the matrix metalloproteinases, influences long bone growth, and consequently may be relevant to growth retardation seen in poor village children and noma victims.Conclusion  These results suggest that occurrence of fresh noma was probably programmed very early in life by malnutrition and chronic infections resulting from replacement of breast milk with contaminated, inferior substitutes. Although not investigated, we speculate that children with fresh noma might also be victims of intrauterine growth retardation as noma is most prevalent during the infantile phase of child growth which starts at mid‐gestation and tails off at 4 years.
Disparities in parasitic infections, perceived ill health and access to health care among poorer and less poor schoolchildren of rural Côte d'Ivoire
Authors: Raso Giovanna , Utzinger Jürg , Silué Kigbafori D. , Ouattara Mamadou , Yapi Ahoua , Toty Abale , Matthys Barbara , Vounatsou Penelope , Tanner Marcel , N'Goran Eliézer K. 
Published: January 2005

SummaryDifferences in the state of health between rural and urban populations living in Africa have been described, yet only few studies analysed inequities within poor rural communities. We investigated disparities in parasitic infections, perceived ill health and access to formal health services among more than 4000 schoolchildren from 57 primary schools in a rural area of western Côte d'Ivoire, as measured by their socioeconomic status. In a first step, we carried out a cross‐sectional parasitological survey. Stool specimens and finger prick blood samples were collected and processed with standardized, quality‐controlled methods, for diagnosis of Schistosoma mansoni, soil‐transmitted helminths, intestinal protozoa and Plasmodium. Then, a questionnaire survey was carried out for the appraisal of self‐reported morbidity indicators, as well as housing characteristics and household assets ownership. Mean travel distance from each village to the nearest health care delivery structure was provided by the regional health authorities. Poorer schoolchildren showed a significantly higher infection prevalence of hookworm than better‐off children. However, higher infection prevalences of intestinal protozoa (i.e. Blastocystis hominis, Endolimax nana and Iodamoeba bütschlii) were found with increasing socioeconomic status. Significant negative associations were observed between socioeconomic status and light infection intensities with hookworm and S. mansoni, as well as with several self‐reported morbidity indicators. The poorest school‐attending children lived significantly further away from formal health services than their richer counterparts. Our study provides evidence for inequities among schoolchildren's parasitic infection status, perceived ill health and access to health care in a large rural part of Côte d'Ivoire. These findings call for more equity‐balanced parasitic disease control interventions, which in turn might be an important strategy for poverty alleviation.
Pseudomonas aeruginosa isolates recovered from clinical and environmental samples in Buea, Cameroon: current status on biotyping and antibiogram
Authors: Ndip R. N. , Dilonga H. M. , Ndip L. M. , Akoachere J. F. K. , Nkuo Akenji T. 
Published: January 2005

SummaryObjective  The study was aimed at determining the prevalent biotypes of Pseudomonas aeruginosa in the environment of Buea and the susceptibility of isolates to antibiotics.Methods  One hundred and fifty clinical specimens (urine, wound and sputum) collected from patients attending various health institutions in Buea, and 50 environmental swabs from furniture, appliances and surroundings of these institutions were screened for P. aeruginosa using standard microbiological and biochemical methods. Antimicrobial susceptibility of the isolates was determined by the disc diffusion assay.Results  Fifty‐one (25.5%) of the 200 specimens were positive for the organism with urine (30%) being the most common source of isolation. Biochemical characterization grouped the isolates into eight biotypes with biotypes B III (25.59%), B II (23.53%) and B I (21.57%) being the most prevalent. Antimicrobial susceptibility results of isolates revealed 13 antibiotype patterns based on resistance to the antimicrobial agents investigated. The resistance pattern, cefotaxime, gentamicin and tetracycline (CTXR GENR TETR) was the most common (21.6%) amongst the isolates. Over 40% of the isolates exhibited multi‐drug resistance to five or more antibiotics, especially environmental isolates. However, there was a significant difference (P < 0.05) in the susceptibility of isolates to ciprofloxacin (98%), amikacin (90.2%) and netilmicin (80.4%) compared with other drugs used in the study.Conclusion  A combination of biotyping and antibiogram, which are relatively cheap and routinely available methods in our environment, could be useful for clinical and epidemiological studies particularly in laboratories in the developing world with limited resources.
Spatial effects of the social marketing of insecticide‐treated nets on malaria morbidity
Authors: Abdulla S. , Gemperli A. , Mukasa O. , Armstrong Schellenberg J. R. M. , Lengeler C. , Vounatsou P. , Smith T. 
Published: January 2005

SummaryRandomized controlled trials have shown that insecticide‐treated nets (ITNs) have an impact on both malaria morbidity and mortality. Uniformly high coverage of ITNs characterized these trials and this resulted in some protection of nearby non‐users of ITNs. We have now assessed the coverage, distribution pattern and resultant spatial effects in one village in Tanzania where ITNs were distributed in a social marketing programme. The prevalence of parasitaemia, mild anaemia (Hb <11 g/dl) and moderate/severe anaemia (Hb <8 g/dl) in children under five was assessed cross‐sectionally. Data on ownership of ITNs were collected and inhabitants’ houses were mapped. One year after the start of the social marketing programme, 52% of the children were using a net which had been treated at least once. The ITNs were rather homogeneously distributed throughout the village at an average density of about 118 ITNs per thousand population. There was no evidence of a pattern in the distribution of parasitaemia and anaemia cases, but children living in areas of moderately high ITN coverage were about half as likely to have moderate/severe anaemia (OR 0.5, 95% CI: 0.2, 0.9) and had lower prevalence of splenomegaly, irrespective of their net use. No protective effects of coverage were found for prevalence of mild anaemia nor for parasitaemia. The use of untreated nets had neither coverage nor short distance effects. More efforts should be made to ensure high coverage in ITNs programmes to achieve maximum benefit.
Experience of targeting subsidies on insecticide‐treated nets: what do we know and what are the knowledge gaps?
Authors: Worrall Eve , Hill Jenny , Webster Jayne , Mortimer Julia 
Published: January 2005

SummaryWidespread coverage of vulnerable populations with insecticide‐treated nets (ITNs) constitutes an important component of the Roll Back Malaria (RBM) strategy to control malaria. The Abuja Targets call for 60% coverage of children under 5 years of age and pregnant women by 2005; but current coverage in Africa is unacceptably low. The RBM ‘Strategic Framework for Coordinated National Action in Scaling‐up Insecticide‐Treated Netting Programmes in Africa’ promotes coordinated national action and advocates sustained public provision of targeted subsidies to maximise public health benefits, alongside support and stimulation of the private sector. Several countries have already planned or initiated targeted subsidy schemes either on a pilot scale or on a national scale, and have valuable experience which can inform future interventions. The WHO RBM ‘Workshop on mapping models for delivering ITNs through targeted subsidies’ held in Zambia in 2003 provided an opportunity to share and document these country experiences. This paper brings together experiences presented at the workshop with other information on experiences of targeting subsidies on ITNs, net treatment kits and retreatment services (ITN products) in order to describe alternative approaches, highlight their similarities and differences, outline lessons learnt, and identify gaps in knowledge. We find that while there is a growing body of knowledge on different approaches to targeting ITN subsidies, there are significant gaps in knowledge in crucial areas. Key questions regarding how best to target, how much it will cost and what outcomes (levels of coverage) to expect remain unanswered. High quality, well‐funded monitoring and evaluation of alternative approaches to targeting ITN subsidies is vital to develop a knowledge base so that countries can design and implement effective strategies to target ITN subsidies.