bluuebunny/crossref_metadata_2025 huggingface dataset:
Topical Lidocaine Medicated Plaster 5% and Pregabalin for the Treatment of Post-Herpetic Neuralgia: A Systematic Review and Meta-Analysis
Authors: Moria Hassan A.
Published: March 2022

Background and objectives: Post-herpetic neuralgia is common severe pain that leads to poor quality of life. Various topical and systemic drugs were in use including topical lidocaine medicated plaster 5% (05% LMP. This is the first meta-analysis to compare 5% lidocaine medicated plaster and pregabalin. Thus, this study aimed to assess the effectiveness of 5% LMP and pregabalin in PHN and compare these medications regarding the same.

Methods: We searched PubMed, MEDLINE, Google Scholar, EBSCO, and Cochrane Library for publications assessing 5% lidocaine medicated plaster and pregabalin drugs on post-herpetic neuralgia. We included articles published in English from inception up to February 2022. All types of studies were included except case reports, case series, studies on animals, and experimental studies. The terms used were: 5% lidocaine medicated plaster, pregabalin, post-herpetic neuralgia, pain relief, pain reduction, and pain scores. We identified 579 articles and the number stood at 435 after duplication removal, of them, 45 full texts were screened. Eight cohorts from seven studies were included in the final meta-analysis. The most recent RevMan system was used for data analysis.

Results: The pain score was significantly lower among patients receiving topical lidocaine compared to placebo or pre and post-intervention (odd ratio, -1.91, 95% CI, -3.77-0.04). Lidocaine Medicated Plaster 5% and pregabalin were effective for pain relief in PHN. However, 5% LMP was more effective (odd ratio, 2.11, 95% CI, 1.41-3.17).

Interpretation and Conclusion: Five % lidocaine medicated plaster was effective for the treatment of post-herpetic neuralgia. In addition, the drug was more beneficial than placebo and pregabalin. Further randomized controlled studies assessing the use of LMP 5% on acute herpes zoster and post-herpetic neuralgia are recommended.
Haematological Patterns of Anaemia in Geriatric Patients and Its Etiology: A Study of 500 Cases
Authors: Agarwal Neha , Kumar Col. Harsh , Jose Merin , Paul Barnali , Patil Ume Sumayya M. , Iqbal M. B. , Gore Charusheela R.
Published: March 2022

Introduction: Anaemia in the elderly is a global health problem, since it is associated with significant morbidity and mortality. The World Health Organization’s criteria consider anaemia when level of haemoglobin is less than 13g/dl in male and 12g/dl in female. Anaemia is easier to miss among the elderly because symptoms such as fatigue, generalized weakness, or mental confusion can be linked to the ageing process. However, anaemia should never be considered as a natural part of growing older.

Aim: To investigate the haematological pattern of anaemia and its underlying etiology in elderly Indian patients.

Materials and Methods: A prospective study undertaken over a span of 2 years in a tertiary care hospital in Western Maharashtra. The study included 500 geriatric (>65years) anaemic patients who underwent a complete haemogram and the results were correlated with peripheral blood smear findings. Other diagnostic tests were done as indicated.

Results: The spectrum encompassed all patterns of anaemia with the most common being normocytic normochromic pattern (57.26%). Overall, there was slight male preponderance (53%) with 65-74 years (69%) being the most common age group afflicted. Maximum number of elderly people had moderate anaemia(56%) in this study; and chronic disease (27.2%) was the most common etiological cause of anaemia followed by iron deficiency (23.4%). Upper gastrointestinal lesions (59%) were the most common causes of iron deficiency anaemia in the present study followed by nutritional deficiency (31.6%).

Conclusion: Correlation of haemogram and peripheral blood smears is a crucial first step to identify the haematological pattern of anaemia and advise subsequent investigations for assessing and diagnosing it’s etiology. Thus, it plays a role in deciding the management protocol and contributes towards a better quality of life for geriatric anemic patients.
An Overview on Implantable Drug Delivery System
Authors: Fulzele Sandip , Bavaskar Sunil R. , Gayakwad Bhushan P. , Sawale Jyotiram , Yadav Reenu , Gauttam Vinod
Published: March 2022

Drug delivery systems that can sustain therapeutic medication doses that are pharmacologically efficacious for long time spans while also permitting "dosing-on-demand" would be immensely useful in modern medicine. Physicians can choose from a variety of precision delivery options, such as local or systemic circulation, while still ensuring appropriate dose over the duration of treatment with implantable drug delivery systems. These systems have several advantages, including focused local medication delivery at a steady and predetermined pace, which reduces the amount of medication required and the associated negative effects while boosting the efficacy of treatment. These systems are especially useful for conditions including Management of cardiovascular disease, TB, diabetes, cancer, and chronic pain, to mention a few, that require long-term medication or face issues with patient compliance. The first section of this chapter provides an overview of different implantable drug delivery devices, ranging from biomaterial-based to electromechanical. Techniques for optimizing medication delivery are also explored, including approaches to alter drug release patterns and the release kinetics process. After that, prospective therapeutic applications and biocompatibility issues will be briefly discussed. These systems' performance and related applications differ. The performance, functioning principle, fabrication procedures, and dimensional constraints of each technology are highlighted. We look at the current research on implanted drug delivery systems, with an emphasis on application and chip performance, as well as a comparison of passive and active delivery systems. Finally, this article sums up with an overview of implantable drug delivery systems' future prospects, particularly in terms of precision and customised medicine.
Synthesis of Phyto Based Metal Nanoparticles: A Green Approach
Authors: Elizabeth M. Kezia , Devi R. Uma , Raja K. Phani , Krishna K. Bala
Published: March 2022

In recent years, changing material properties is gaining a significant research interest. Besides, applying the fundamentals of basic science to different applications is also more encouraged and on-demand. In this view, material science has become a common interest in various fields, starting from chemistry, physics, biology, and engineering. The common platform for all these sectors is nanoscience and nanotechnology. The main motto is changing material properties while converting it from bulk to its nano size level. The changes in properties like optical, mechanical, and others make the synthesized nanomaterials for implementation in various applications for humankind. Besides the success of this idea, the toxicity of the materials used during the synthesis becomes a question to researchers, as it hinders the sustainable development concept. If not total, a certain decrement in the toxic material utilization gives a pavement towards green technology. In this view, various researchers adopted plant materials as sources for synthesizing the nanomaterial in this decade. The present review highlights the utilization of coinage metal (Ag, Au, and Cu) salt to synthesize nanoparticles by using plant sources like leaf, bark and their characterization study along with their applications.
Diagnosis, Treatment, and Outcomes of Presumed Ocular Tuberculosis Patients Attending Central Chest Clinic, Colombo
Authors: Dilahara Tilakaratne , Malith Kumarasinghe
Published: March 2022

Aims: Main objective of this study was to describe the diagnosis, treatment, outcomes, and associated factors of presumed ocular tuberculosis patients attending Central Chest Clinic, Colombo. 

Study Design, Place and Duration: A cross sectional descriptive study was conducted among all ocular tuberculosis patients referred to Central Chest Clinic, Colombo for treatment from 1st of January 2016 to 31st June 2018.

Methodology: Pretested content validated secondary data extraction form was used. Socio-demographic and work-related characteristics were analysed using frequency distributions. Association between socio-demographic characteristics and factors associated with diagnosis, treatment and outcomes were analysed using Fisher-extract test. 

Results: Among study respondents, 52.6% showed abnormal ESR finding (>20mm), 17.8% displayed Chest X-ray abnormalities and 89.5% reported positive Tuberculin skin test (>14mm in diameter). Uveitis was the most common diagnosis (87.9%). Among Uveitis patients, 36.5% presented with posterior uveitis. Out of all ocular TB patients who have completed the treatment, 77.6% reported improvement of vision following the anti-TB treatment regimen. Duration of the treatment with anti-TB drugs was similar across all types of ocular diseases among Ocular TB patients (p=0.590).

Conclusions: Large number of patients received treatment for 6 months with majority reported as improved vision on completion of treatment. Further prospective studies using primary data need to be conducted to have greater insight of the ocular tuberculosis in Sri Lanka.
The Application of Little’s Effect and Ferrochemistry for New Approach for Extraction of LIOH from Salar Geothermal Brines
Authors: B. Little Reginald
Published: March 2022

A prior theory of Ferrochemistry and its Laws for Little’s Rules 1, 2 and 3 are applied to systems of nuclear spins and nucleon angular momenta for using applied static magnetic fields, static electric fields, ultrasonic vibrations, and radio frequency waves for stimulating, separating and extracting various cations from geothermal, salar brines.  Down the group and families of alkali, alkaline earth and halide ions, considerations are given of variations in e- e- --- e- e-  --- e- interactions and e- e- --- nuclear interactions from s to p to d to f subshells with complex inter and intra orbital, subshell and shell interactions.  The unique symmetry of s orbital for reversibly collapsing on nuclei and vice versa nuclei fractionally, reversibly fissing for nuclear pressures into s orbitals and from s subshells into outer subshells of higher azimuthal quanta are given.  The alterations of the electronic shells and variations among elements and their isotopes are disclosed to cause the novel mechanics for separating the alkali cations and lithium, specifically.  An analogy is draw between extractions of Li+, Na+, K+, Mg2+ and Ca2+ cations in graphene-nanodiamond nanofiltering membrane and variations of these ions in ion channels of brain and nervous systems in animals and humans for determining new mechanics of diseases like mania, depression, and bipolar disorder with treatments by Li+ is considered.  Advantages of this graphene, nanodiamond nanofilter relative to current methods are considered.  Details of the mechanics on basis of varying sizes of s orbitals, symmetries of s orbitals, varying rotation rates of the cations, varying spins of the cations, and varying nuclear magnetic moments (NMMs) of the cations are presented.  The originality of the author’s theory of invoking NMMs for differing interactions is contrasted with prior nuclear spin effects of prior investigators. Complex spin and angular momenta interactions of the cations, anions, protons and halides are considered.  A novel method of using the static magnetic field, static electric fields, radio frequency waves and ultrasounds for selective precipitations of LiOH (s) with retarding Li2CO3 (s) is presented. The ultrasounds and radio waves may agitate in operation to prevent clogging of the graphene/nanodiamond nanofiltration membrane. On the basis of separation factors (ξ) as by ratios of various NMMs of the cations in geothermal salar brines, the separation factor varies from: ξ(Li+/Na+) = 1.45; to ξ(Li+/K+) = 8.35 to ξ(Co/Li) = 0.607 to ξ(Co/Mn) = 0.635. The similar, large NMMs of Li with Co and Mn with small differences in spins may by the theory here be the explanation and cause for more difficult separation of Li from Co and Mn and the current empirical affinity of Li for Co and Mn as indeed Co and Mn have been observed as sorbents for Li.
Bidirectional Controlled Teleportation of Two-qubit and Three-qubit State via Nine-qubit Entangled State
Authors: Wang Jinwei
Published: March 2022

In this paper, a bidirectional controlled quantum teleportation via a nine-qubit entangled state is given. In this scheme, Alice wants to teleport a two-qubit entangled state to Bob and Bob wants to teleport arbitrary three-qubit state to Alice at the same time. The quantum teleportation is supervised by a controller. We firstly product a nine-qubit entangled states by the states |000000000⟩, and then we use this entangled states as quantum channel to transfer quantum information along three nodes. This scheme is efficient and economical because the intrinsic efficiency reaches 5/19.
Financial Inclusion: A Panacea for Economic Growth in Nigeria (2004 – 2020): An Empirical Review
Authors: Emmanuel Uzoma Makwe , Olushola Oladele Akeeb , Chikamnele Ibechiole Onyekachi
Published: March 2022

Financial inclusion has been considered as one of the most potent drivers of economic growth in countries across the globe, this is in view of the fact that financial inclusion creates access to financial resources which affords individuals the opportunity to participate in inclusive growth. The purpose of this paper was to provide a conceptual understanding of financial inclusion and the economic growth components, these variables were adequately reviewed and the relationship between both established. Empirical literatures on the subject matter were reviewed and the position of majority of the authors established. An empirical analysis was conducted to ascertain the relationship between financial inclusion and economic growth and the outcome revealed that financial inclusion promotes economic growth in Nigeria. The recommendations of this study includes the following amongst others; government should enact laws that will make financial services/resources readily accessible to those in the rural and remote communities in Nigeria so as to integrate them into the emerging financial order of the Nigerian financial system; Micro finance banks should be encouraged to intensify operations in remote communities as they can serve as intermediaries between the people in the local communities and the deposit money banks dominant in the urban areas.
Exchange Rate and Capital Flight: An Empirical Analysis
Authors: Otieno Shem , Mose Naftaly , Thomi John
Published: March 2022

Exchange rate volatility and declining capital inflow are important policy issues that inform macroeconomic policies and strategies of developing countries. Most developing economies have small potential resource base, faces foreign exchange volatility and limited market of agricultural products, thus investigating the role of capital flight is significant for these states. Cognizant of this, the study will try to answer the paradox of capital outflow and exchange uncertainty. The research will investigate the influence of exchange rate differential on capital flight in East Africa economies for the year 1988-2018 using panel secondary data. The empirical analysis was guided by investment creation theorem. The study adopted ordinary least squares estimation to analyse the relation between the study variables. The study estimations has identified that exchange rate positively influences capital outflow in East African states. The positive effect of currency change on capital outflow implied that capital outflow was sensitive to currency depreciation. Accelerated currency devaluation erodes domestic investors confidence to hold local currency, citizens will likely move to foreign markets and assets to avoid negative effect of devaluation. Government policymakers should pursue strategies and policies that can slow currency uncertainty in order to tame capital outflow. These policies and strategies include fostering of both fiscal and monetary disciplines and good governance.
Interaction of cysteine proteinases with recombinant kininogen domain 2, expressed in Escherichia coli
Authors: Ylinenjärvi Karin , Prasthofer Thomas W. , Martin Nancy C. , Björk Ingemar
Published: July 2002

The calpain‐binding domain 2 of the kininogens, the major plasma inhibitors of cysteine proteinases, was expressed in Escherichia coli. Expression of soluble protein was optimal at 15°C and was augmented by growing the bacteria in sorbitol and betaine. The recombinant domain showed high affinity (K

i
0.3–1 nM) for cathepsin L and papain, and a somewhat lower affinity (K

i
∼ 15 nM) for calpain. The binding to cathepsin H was substantially weaker, and no inhibition of actinidin and cathepsin B was detected. The affinity for cathepsin L was comparable to that reported for the domain isolated from plasma L‐kininogen, whereas the affinities for papain and calpain were about tenfold lower. The latter difference may be due to the recombinant domain being nonglycosylated.
Identification of lysophospholipid receptors in human platelets: the relation of two agonists, lysophosphatidic acid and sphingosine 1‐phosphate
Authors: Motohashi Ken , Shibata Satomi , Ozaki Yukio , Yatomi Yutaka , Igarashi Yasuyuki
Published: July 2002

Lysophosphatidic acid (LPA) and sphingosine 1‐phosphate (Sph‐1‐P) are known as structurally related bio‐active lipids activating platelets through their respective receptors. Although the receptors for LPA and Sph‐1‐P have been recently identified in various cells, the identification and characterization of ones in platelets have been reported only preliminarily. In this report, we first investigated the distinct modes of LPA and Sph‐1‐P actions in platelet activation and found that LPA functioned as a much stronger agonist than Sph‐1‐P, and high concentrations of Sph‐1‐P specifically desensitized LPA‐induced intracellular Ca2+ mobilization. In order to identify the responsible receptors underlying these observations, we analyzed the LPA and Sph‐1‐P receptors which might be expressed in human platelets, by RT‐PCR. We found for the first time that Edg2, 4, 6 and 7 mRNA are expressed in human platelets.
Aberrant overexpression of 53BP2 mRNA in lung cancer cell lines
Authors: Mori Toshiyuki , Okamoto Hiroshi , Takahashi Naoko , Ueda Ryuzo , Okamoto Takashi
Published: July 2002

The p53‐binding protein 2 (53BP2) was identified as a binding protein to a tumor suppressor p53. We examined the genetic aberrations of 53BP2 gene in various human cancer cell lines. Although no gross genomic alteration or mutation of 53BP2 gene was observed, 53BP2 mRNA levels were highly variable. There was no association between the 53BP2 mRNA level and the p53 status. When we examined sensitivities of these cell lines to DNA‐damaging agents including UV irradiation, X‐ray irradiation and cis‐diamine‐dichloroplatinum (CDDP), we found that higher 53BP2 mRNA expression was correlated with the sensitivity to these agents.
Relationship between stream temperature, thermal refugia and rainbow trout Oncorhynchus mykiss abundance in arid‐land streams in the northwestern United States
Authors: Ebersole J. L. , Liss W. J. , Frissell C. A.
Published: July 2002

Abstract
–
Warm stream temperatures may effectively limit the distribution and abundance of Pacific salmon Oncorhynchus spp. in streams. The role of cold thermal refugia created by upwelling groundwater in mediating this effect has been hypothesized but not quantitatively described. Between June 21 and September 15, 1994, rainbow trout O. mykiss abundance within 12 northeast Oregon (USA) stream reaches was inversely correlated with mean ambient maximum stream temperatures (r=−0.7, P<0.05). Some rainbow trout used thermal refugia (1–10 m2 surface area) that were on average 3–8°C colder than ambient stream temperatures. Within the warmest reaches, high ambient stream temperatures (>22°C) persisted from mid‐June through August, and on average 10–40% of rainbow trout were observed within thermal refugia during periods of midday maximum stream temperatures. Frequency of cold‐water patches within reaches was not significantly associated with rainbow trout density after accounting for the influence of ambient stream temperature (P=0.06; extra sum of squares F‐test). Given prolonged high ambient stream temperatures in some reaches, the thermal refugia available in the streams we examined may be too small and too infrequent to sustain high densities of rainbow trout. However, these refugia could allow some rainbow trout to persist, although at low densities, in warm stream reaches.
NBR1 interacts with fasciculation and elongation protein zeta‐1 (FEZ1) and calcium and integrin binding protein (CIB) and shows developmentally restricted expression in the neural tube
Authors: Whitehouse Caroline , Chambers Julie , Howe Kathy , Cobourne Martyn , Sharpe Paul , Solomon Ellen
Published: July 2002

NBR1 (named as next to BRCA1) was originally cloned as a candidate gene for the ovarian cancer antigen CA125, using expression cloning with the anti‐CA125 Ig, OC125. NBR1 has been of interest due to its position close to BRCA1, although no involvement in breast or ovarian cancer has been demonstrated. Recently, the antigen CA125 has been cloned, and identified as a new mucin, MUC16, entirely different from NBR1. The function of NBR1 remains unknown. To investigate its function, a yeast two‐hybrid study was performed to identify interacting protein partners that may reflect a biological role for this protein. Here, we show that NBR1 interacts with two proteins; fasciculation and elongation protein zeta‐1 (FEZ1), a PKCζ interacting protein, and calcium and integrin binding protein (CIB), which is associated with polo‐like kinases Fnk/Snk and the Alzheimer's disease presenilin 2 protein. Co‐transfection of FEZ1 and NBR1 showed overlapping localization in the cytoplasm, whereas coexpression of NBR1 and CIB resulted in a shift of CIB protein expression from the nucleus to the perinuclear compartment. FEZ1 is highly expressed in the brain and in situ hybridization analysis of Nbr1 showed that its expression is also regulated in the murine brain during development. These data suggest that NBR1 may function, through interaction with CIB and FEZ1 in cell signalling pathways, with a developmentally restricted expression suggesting a possible role in neural development.
The prognostic impact of karyotypic subgroups in myelodysplastic syndromes is strongly modified by sex
Authors: Mauritzson N. , Johansson B. , Rylander L. , Albin M. , Strömberg U. , Billström R. , Ahlgren T. , Mikoczy Z. , Mitelman F. , Hagmar L. , Nilsson P. G.
Published: July 2002

The prognostic impact of karyotypic patterns in a consecutive series of 389 adult myelodysplastic syndromes (MDS) was investigated. Time period did not significantly influence the survival times. In the analyses, the MDS cases were subdivided into the cytogenetic subgroups used in the International Prognostic Scoring System, i.e. favourable [–Y, del(5q) or del(20q) as single aberrations or normal karyotype, n = 241], poor [−7, del(7q), der(1;7) or complex karyotypes, i.e. ≥ three abnormalities, n = 89] and intermediate (other aberrations, n = 59). The survival times correlated well with the prognostic subgroups, confirming that the cytogenetic classification was valid. Expressed as hazard ratios (HRs), with the favourable subgroup as the reference, the intermediate and poor subgroup HRs increased to 1·5 (95% confidence interval, 1·1–2·1) and 3·2 (2·4–4·1) respectively. Sex, age, morphological subtype and smoking habits significantly modified this prognostic impact. Shorter survival was detected for men in the favourable and the intermediate subgroups, but not in the poor prognosis subgroup. Using women in the favourable subgroup as the reference and adjusting for age, the HR for men was 1·6 (1·2–2·1) in the favourable subgroup. Adjusting for smoking habits as well decreased the HR to 1·4 (1·1–2·0) and, when also excluding cases with del(5q) as the sole anomaly, no significant difference could be discerned [HR 1·2 (0·9–1·6], suggesting that the better outcome for women in the favourable subgroup was mainly as a result of the ‘5q‐syndrome’ and to smoking habits. In the intermediate subgroup, the corresponding HRs were 3·0 (1·5–6·0) when adjusted for age and 2·7 (1·3–5·5) when also adjusted for smoking habits. Different survival times between men and women have never previously been reported for this MDS group. Although it remains to be elucidated whether environmental and/or constitutional factors cause the observed sex‐related difference, these observations have obvious clinical ramifications, not least in designing and evaluating therapy protocols.
Long‐term changes in over‐winter survival rates explain the decline of reed buntings Emberiza schoeniclus in Britain
Authors: Peach Will J. , Siriwardena Gavin M. , Gregory Richard D.
Published: July 2002

1. The reed bunting Emberiza schoeniclus is one of a suite of granivorous farmland bird species that suffered a major population decline in Britain during the late 1970s and early 1980s. Extensive monitoring data indicate a large increase in the abundance of reed buntings between 1963 and 1975, followed by a decline of 58% on farmland and 66% along linear waterways during the period 1975–83. Since 1983 numbers have remained relatively stable in both habitats.

2. During the population decline, breeding numbers declined rapidly on arable and mixed farms, but remained relatively stable on pastoral farms. The decline on farmland was greater in northern Britain than in the south‐east.

3. Extensive nest recording indicated that breeding performance was higher during the period of population decline (2·74 young per nesting attempt) than during the preceding period of population increase (2·65) or the recent period of population stability (2·17).

4. Minimum survival during the first year of life (estimated from mark–recapture data) declined during the 1970s and early 1980s, and increased strongly during the 1990s. The trend in first‐year survival was independent of a weak positive relationship with winter temperature. Although there was evidence of a similar temporal trend in adult survival, this disappeared when winter temperature was taken into account.

5. A demographic model indicated that the timing and magnitude of the observed changes in first‐year survival and adult survival were each sufficient alone to account for the observed changes in the abundance of reed buntings during the period 1969–87. A reduction in over‐winter survival was probably the main demographic cause of the reed bunting population decline, although loss of breeding habitat and a recent reduction in breeding performance may also have influenced numbers.

6. During winter reed buntings feed mainly on small grass and weed seeds. The observed declines in abundance and survival rates coincide with the widespread introduction of a range of efficient herbicides and the loss of winter stubbles from British farmland. Our findings are therefore consistent with the hypothesis that the decline of the British reed bunting population was caused primarily by a reduction in food availability outside the breeding season. Changes in agricultural practices that increase the abundance of small weed and grass seed on farmland during winter are likely to allow at least a partial recovery of the British reed bunting population.
Corticosteroid Actions in the Hippocampus
Authors: Joëls M.
Published: July 2002

Corticosteroid hormones can enter the brain and bind to two intracellular receptor types that regulate transcription of responsive genes: (i) the high affinity mineralocorticoid receptors and (ii) the glucocorticoid receptors with approximately 10‐fold lower affinity. Although most cells in the brain predominantly express glucocorticoid receptors, principal cells in limbic structures such as the hippocampus often contain glucocorticoid as well as mineralocorticoid receptors. Recent electrophysiological studies have examined the consequences of transcriptional regulation via the two receptor types for information transfer in the hippocampus. It was found that, under resting conditions, corticosteroids do not markedly alter electrical activity. However, if neurones are shifted towards more depolarized or hyperpolarized potentials due to the action of neurotransmitters, slow and adaptive effects of the corticosteroid hormones become apparent. In general, mineralocorticoid receptor occupation maintains steady electrical activity in hippocampal neurones. Brief activation of glucocorticoid receptors leads to increased influx of calcium, which normally helps to slowly reverse temporarily raised electrical activity. These slow and persistent corticosteroid actions will alter network function within the hippocampus, thus contributing to behavioural adaptation in response to stress. Modulation of hippocampal activity by corticosteroids also affects hippocampal output (e.g. to inhibitory interneurones which control hypothalamic‐pituitary‐adrenal axis activity). The enhanced calcium influx after glucocorticoid receptor activation can become a risk factor when cells are simultaneously exposed to strong depolarizing inputs, such as those occuring during ischaemia. Similarly, chronically elevated corticosteroid levels (or lack of corticosteroids) could endanger hippocampal cell function. The latter may contribute to the precipitation of clinical symptoms in diseases associated with chronically aberrant corticosteroid levels.
Wheat‐germ aspartate transcarbamoylase: revised purification, stability and re‐evaluation of regulatory kinetics in terms of the Monod–Wyman–Changeux model
Authors: Khan Ahsan I. , Chowdhry Babur Z. , Yon Robert J.
Published: July 2002

A revised and simplified purification scheme for aspartate transcarbamoylase (ATCase) from wheat‐germ is reported, with an eightfold increase in scale (yielding ≈ 10 mg of the pure protein from 4 kg of wheat‐germ), and improved characteristics of stability and regulatory kinetics. The ATCase obtained is greater than 96% pure, as judged by polyacrylamide gel electrophoresis. The long‐term stability (i.e. on a time‐scale of several hours to weeks) of the activity of the purified enzyme, under various storage conditions, was investigated. At 4 °C and pH 7.5, stability was found to be strongly dependent on protein concentration (increased stability at high concentration), buffer concentration (decreased stability at high buffer concentration) and the inclusion of glycerol (increased stability with increasing glycerol concentration). The enzyme is routinely stored at 4 °C, in 0.05 m Tris/HCl buffer containing 25% glycerol and at high protein concentration (≈ 1 mg·mL−1, or 10 µm in trimers). Under these conditions, the half‐life of the enzyme activity is greater than 300 days. Over the time‐scale of kinetic experiments (up to 20 min), the diluted activity (at around 1 nm of ATCase, in the presence of ligands) is completely stable. The specific activity remains constant in the range 0.1–10 nm, in the absence and presence of ligands, showing that dissociation of the trimeric enzyme into its subunits is negligible. Steady‐state kinetics were examined using the enzyme at a concentration of 1.3 nm. Initial‐rate curves for both allosteric ligands, carbamoylphosphate (CP) and uridine 5′‐monophosphate (UMP), showed pronounced sigmoidicity, each in the presence of the other. In the absence of UMP, initial‐rate curves for CP are hyperbolic. The initial rate data fit reasonably well to a trimeric Monod–Wyman–Changeux model, suggesting a two‐state conformational mechanism, greatly favouring the active (R) state when both ligands are absent, in which the R‐state binds CP exclusively (dissociation constant = 23.2 µm), and the T‐state binds UMP exclusively (dissociation constant = 0.49 µm). This regulatory behaviour was found to be quite stable, and was indistinguishable from that of the enzyme in a freshly made crude extract, even after storage of the pure sample for 5 months. This enzyme preparation is therefore free of the anomalous allosteric kinetics produced by a previous purification scheme, in which the affinity for UMP was markedly reduced, CP rate curves showed no sigmoidicity, while UMP rate curves had sigmoidicity exaggerated by a low maximum.
The long‐term safety of alprostadil (prostaglandin‐E1) in patients with erectile dysfunction
Authors:   THE EUROPEAN ALPROSTADIL STUDY GROUP (see Appendix)
Published: July 2002

Objective

 To evaluate the long‐term safety and efficacy of intracavernosal alprostadil (prostaglandin E1 , PGE1 ) in patients with erectile dysfunction (ED) and assess the feasibility of self‐injection treatment.

Patients and methods

 The study included 848 men (aged 18–75 years) with ED of ≥4 months’ duration. The initial home‐use dose of alprostadil, defined as a dose producing an erection satisfactory for intercourse and lasting for ≥20 min, was determined for each patient in the investigator’s clinic and in the patient’s home. This dose‐finding phase was followed by a 6‐month, self‐injection, home‐maintenance phase. The efficacy and adverse effects were documented.

Results

 An initial home‐use dose was determined for 93% of the patients and in most (86%) it was ≤20 μg. During the 6‐month study period, 88% of injections assessed by the patients resulted in satisfactory sexual activity (intercourse or masturbation) and 90% of injections assessed by partners resulted in satisfactory intercourse. Penile pain occurred in 44% of patients, but this incidence decreased with time. In 52% of patients with pain it was mild and only 3% of patients discontinued the study because of pain. Prolonged erection and priapism occurred in 8% and 0.9% of patients, respectively. Penile fibrosis occurred in 4% of patients. Drug‐related systemic medical events occurred in 5% of patients and none of these were serious. Haemodynamic events occurred in <1% of patients and were not considered to be clinically relevant.

Conclusion

 Intracavernosal alprostadil is an effective and safe therapy for ED, provided that the individual dose is established by titration, patients are trained in the self‐injection technique and supervised periodically.
E′ centers and nitrogen-related defects in SiO2 films
Authors: Stathis J. H. , Chapple-Sokol J. , Tierney E. , Batey J.
Published: July 2002

We have observed an electron paramagnetic resonance signal corresponding to a neutral fourfold coordinated nitrogen in plasma-enhanced chemical vapor deposited SiO2 films fabricated under certain conditions. The same films contain E′ centers (positive oxygen vacancies) in an equal quantity. Our data support a model in which these two paramagnetic centers are created simultaneously by an electron transfer, starting from a positive fourfold nitrogen and a neutral oxygen vacancy. This model allows an earlier observation of an apparently neutral E′ variant to be interpreted as a normal positive E′ plus a nitrogen center to conserve charge.
Nanolithography on semiconductor surfaces under an etching solution
Authors: Nagahara L. A. , Thundat T. , Lindsay S. M.
Published: July 2002

We describe a technique for controllably etching nanometer size features into Si(100) and GaAs(100) surfaces with the scanning tunneling microscope while under a (0.05%) HF solution which dissolves oxides. The etching mechanism appears to be due to a field-induced oxide growth followed by a chemical etching of the oxide. With this technique, we can etch features as small as 20 nm in linewidth.
Comparison of Si(111) surfaces prepared using aqueous solutions of NH4F versus HF
Authors: Higashi G. S. , Becker R. S. , Chabal Y. J. , Becker A. J.
Published: July 2002

Vacuum scanning tunneling microscopy has been used to investigate the hydrogen-terminated Si(111) surfaces obtained upon dissolution of the native oxide in HF and NH4F solutions. Whereas etching in aqueous HF acid produces an atomically rough surface, comparable treatment in NH4F results in atomically flat surfaces. These atomically flat surfaces are extremely well ordered and exhibit terraces which extend thousands of angstroms.
Swelling of plasma-polymerized tetrafluoroethylene films
Authors: Butler M. A. , Buss R. J. , Seager C. H.
Published: July 2002

Swelling of micrometer thick-films of plasma-polymerized tetrafluoroethylene has been measured for a range of solvents using an optical-interferometric technique. For low gas-phase concentrations of the solvent, the swelling is found to correlate with the ionization potential of the solvent. Photo-thermal deflection spectroscopy of the films shows optical absorption in the infrared, which changes with exposure to different solvents. Both of these results suggest weak electron transfer from the solvent to the polymer as the dominant interaction mechanism.
Room temperature blue light emitting p-n diodes from Zn(S,Se)-based multiple quantum well structures
Authors: Xie W. , Grillo D. C. , Gunshor R. L. , Kobayashi M. , Jeon H. , Ding J. , Nurmikko A. V. , Hua G. C. , Otsuka N.
Published: July 2002

Blue (494 nm) light emitting quantum well diodes based on Zn(S,Se) p-n junctions are demonstrated at room temperature. P-type Zn(S,Se) is realized by using a nitrogen rf plasma cell. The light emitting diode is formed on homoepitaxial GaAs buffer layers by molecular beam epitaxy. The S fraction of the alloy is selected to provide a lattice match between the II-VI active region and the GaAs buffer; the result is an active region having a dislocation density below 105/cm−2. The letter discusses emission characteristics as well as the x-ray rocking curve and transmission electron microscopy characterization of the structures.
Freezing in confined geometries
Authors: Sokol P. E. , Ma W. J. , Herwig K. W. , Snow W. M. , Wang Y. , Koplik Joel , Banavar Jayanth R.
Published: July 2002

Results of detailed structural studies, using elastic neutron scattering, of the freezing of liquid O2 and D2 in porous vycor glass are presented. The experimental studies have been complemented by computer simulations of the dynamics of freezing of a Lennard-Jones liquid in narrow channels bounded by molecular walls. Our results point to a new simple physical interpretation of freezing in confined geometries.
Hydrogen passivation of grain boundary defects in polycrystalline silicon thin films
Authors: Nickel N. H. , Johnson N. M. , Jackson W. B.
Published: July 2002

The dependence of defect passivation in undoped polycrystalline silicon on hydrogenation conditions (i.e., time and temperature) was examined. At long hydrogenation times the spin density NS saturates. The saturation value of NS depends strongly on the hydrogenation temperature. The lowest residual spin density was obtained at 350 °C. Model calculations of the time and temperature dependence of the defect passivation suggest that the amount of hydrogen necessary for defect passivation exceeds the density of grain boundary defects by a factor that is significantly larger than unity and which depends on the hydrogenation temperature.
Time resolved dynamics of subpicosecond laser ablation
Authors: Preuss S. , Späth M. , Zhang Y. , Stuke M.
Published: July 2002

The ablation of lithium niobate (LiNbO3), poly(tetrafluoroethylene) (PTFE, teflon), poly(methylmethacrylate) (PMMA) and polyimide (PI) by 500 fs UV excimer laser pulses at 248 nm is reported. Time-resolved measurements were carried out with pulse pairs of variable delay in the range from −200 to +200 ps. The ablation rate is very sensitive to the time delay between the two pulses, and —depending on the material and fluence—can increase or decrease for very short time delays. For LiNbO3, efficient shielding is observed within a few picoseconds. For PTFE and PMMA, and the total fluence just above threshold, the ablation rate versus time delay shows an autocorrelation type behavior with a full width at half-maximum below 400 fs, since two-photon absorption dominates the ablation process. For polyimide, excited state absorption is found to decrease the ablation rate for delay times below 30 ps.
Electrical properties of cobalt-zinc ferrites
Authors: Kale G. M. , Asokan T.
Published: July 2002

The electrical properties of Co1−xZnxFe2O4 (x=0–1) spinel ferrites were investigated by impedance spectroscopy. The grain-boundary resistance was found to increase as a function of composition up to x=0.6, and decreases beyond x=0.6. The variation in the bulk resistance and the activation energy as a function of composition is found to exhibit a similar trend whereas the grain resistance appears to be an independent parameter. The observed results suggest that the bulk properties of solid solution spinel ferrites are primarily controlled by the grain-boundary phase.
Multifunctional, micropipette based force cantilevers for scanned probe microscopy
Authors: Lieberman Klony , Lewis Aaron , Fish Galina , Shalom Shmuel , Jovin Thomas M. , Schaper Achim , Cohen Sidney R.
Published: July 2002

We demonstrate quartz micropipette and optical fiber based structures with unique applications for scanned probe microscopy. These probes are produced by drawing, cantilevering, and polishing tapered micropipettes and optical fibers and have significantly greater potential functionality than any other currently available scanning tip. We present normal force, contact mode imaging of a selection of surfaces, operating these probes with different commercial instruments for atomic force microscopy (AFM). With their very sharp tips, ultrahigh aspect ratios, and readily adjustable force constants and resonance frequencies, the probes present an attractive alternative to conventional microfabricated cantilevers that are currently in routine use with AFM. Bent quartz optical fiber probes also enable simple integration of near-field scanning optical microscopy and AFM.
Structural study of diamond film formed on silicon wafer by hot-filament chemical vapor deposition method
Authors: Yang Jie , Lin Zhangda , Wang Li-Xin , Jin Sing , Zhang Zhe
Published: July 2002

Very important evidence has been obtained by high-resolution cross-sectional electron microscopy (HREM) that diamond films prepared by the hot-filament chemical vapor deposition (HFCVD) method were grown epitaxially on the mirror-polished Si(100) substrate in a local area with surface biasing pretreatment. There is about a 7.3° angle between Si (100) and D(100) heteroepitaxial crystalline planes. The same type of twinnings (coherent twin boundaries of type, Σ=3) exist on and near the interface. High preferential oriented diamond films have been observed by scanning electron microscopy (SEM). From the discussion, the pretreatment of the substrate is a key factor for the heteroepitaxy of diamond on Si wafer.
Preparation and ferroelectric properties of SrBi2Ta2O9 thin films
Authors: Amanuma Kazushi , Hase Takashi , Miyasaka Yoichi
Published: July 2002

Ferroelectric SrBi2Ta2O9 thin films were synthesized on Pt/Ti/SiO2/Si substrates using a solution deposition process, and structural and electrical properties were investigated. The spin-on films crystallized during firing above 700 °C. The films showed high diffraction peaks of (105) and (200), while little peaks from (00l) planes were observed. Good ferroelectric properties were obtained for a 280 nm thick film; Pr and Ec were 10.0 μC/cm2 and 38 kV/cm, respectively. Fatigue endurance was excellent; the hysteresis loop does not change up to 109 switching cycles. These properties are very attractive for nonvolatile memory application.
High-sensitivity helium resonance magnetometers
Authors: McGregor Douglas D.
Published: July 2002

A number of techniques to improve the sensitivity of helium resonance magnetometers is explored. Using a mathematical model of the helium cell discharge and optical pumping process, calculations indicate that substantial gains in sensitivity of a He4 magnetometer are possible. The improvements are obtained by use of larger cells and the replacement of the lamp with a laser as the source of pump radiation. A large cell (2 in. diameter×6 in. long) magnetometer with lamp pumping is calculated to have a sensitivity of 3×10−4 γ/(Hz)1/2, a value which has been experimentally verified. The projected sensitivity of a laser-pumped magnetometer varies between 2×10−5 and 4×10−6 γ/(Hz)1/2, depending on cell size.
Development of the electromagnetically launched expanding ring as a high-strain-rate test technique
Authors: Gourdin W. H. , Weinland S. L. , Boling R. M.
Published: July 2002

Improvements to the electromagnetically launched expanding ring experiment that make the technique more reproducible, analyzable, and amenable to the rapid testing of many specimens are presented. Aspects of the design and containment of the primary solenoid, high-voltage switching, and electromagnetic diagnostics are discussed, and a new method for launching specimens of low conductivity is described. The reproducibility of the method is demonstrated for oxygen-free electronic (OFE)copper and tantalum rings.
Electron cyclotron resonance sources for wide and narrow plasma streams
Authors: Popov Oleg A. , Westner August O.
Published: July 2002

Characteristics, performance, and design features of 3- and 6-in. diam electron cyclotron resonance plasma stream sources are presented. Three types of plasma streams were found and studied: (1) uniform with low-level microwave power absorption and low plasma density, (2) nonuniform narrow column or ring with high-level microwave power absorption and plasma density, and (3) large-area (wide) uniform stream with moderate plasma density. It was found that the highest plasma densities in streams were reached when the magnetic field near the vacuum window was 875 and 935 G. With microwave power of 800–1000 W and gas pressures of 2–6×10−4 Torr (argon, nitrogen, oxygen), both 3- and 6-in. sources can deliver at distance of 30 cm uniform streams with plasma densities of 4–6×1010 cm−3 and uniformity of ±5% over an area larger than 15 cm in diameter.
Spectroscopic study of edge poloidal rotation and radial electric fields in the DIII-D tokamak (invited)
Authors: Groebner R. J. , Burrell K. H. , Gohil P. , Seraydarian R. P.
Published: July 2002

Doppler-shift spectroscopy has shown that finite values of poloidal rotation velocity vθ and of radial electric field Er exist at the edge of a tokamak plasma and that dramatic increases occur in these parameters at an L-H transition. Er is negative in the L mode and becomes more negative in the H mode; vθ increases in magnitude at the transition. In addition, the radial gradients (shear) of vθ and Er are large and these gradients also increase at the L-H transition. These results are based on measurements of Doppler shifts of light emitted by He II ions, located in a region about 1–3 cm inside the separatrix. These observations have been made with horizontally viewing and vertically viewing spectrometer systems on the DIII-D tokamak. The nearly orthogonal views of these systems are used to determine the plasma’s flow velocity in terms of the orthogonal sets vθ and vφ or of v⊥ and v∥. Knowledge of v⊥ is used to calculate Er from the force balance equation for a single ion species. The existing results impose constraints on theories of the L-H transition. More detailed studies of the spatial profiles and temporal evolution of vθ and Er will be made with upgraded instrumentation, which is now coming on-line.