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This paper introduces an innovative manufacturing method for NdFeB magnets, involving the integration of reduced graphene oxide (rGO) during mechanical milling (MM) to counteract powder ignition, a common issue in oxygen-rich environments. The NdFeB alloy underwent hydrogen decrepitation before being mechanically milled with varying rGO quantities in ambient air. Raman and X-ray diffraction (XRD) analyses confirmed the successful production of rGO samples with a minimal number of layers. The XRD analysis of the NdFeB/rGO powder demonstrated that all the diffraction peaks corresponded to the Nd2Fe14BH1.86 phase, with no carbides or other carbon compounds detected. Transmission electron microscopy revealed rGO encapsulating the NdFeBrGO particles, while scanning electron microscopy of the resulting magnets (samples 1, 2, and 3) displayed grain sizes ranging from 0.5 µm to 6.8 µm. These manufacturing variations led to a diverse range of magnetic properties: remanence (Br) varied from 0.5 T to 1.13 T, intrinsic coercivity (iHc) ranged from 263.5 kA m−1 to 776.1 kA m−1, and maximum energy product (BHmax) spanned from 21.0 kJ m−3 to 232.3 kJ m−3. Remarkably, the most favorable Br, iHc, and BHmax values were observed in Sample 0.02 wt.% rGO, closely aligning with the characteristics typically found in commercial NdFeB. [ABSTRACT FROM AUTHOR]

Although complete remission (CR) is achieved in 50 to 70% of older fit patients with acute myeloid leukemia (AML), consolidation therapy in this age group remains challenging. In this retrospective study, we aimed to compare outcome in elderly patients treated with different post-remission modalities, including allogenic and autologous hematopoietic stem cell transplantation (HSCT), intensive chemotherapy, and standard-dose chemotherapy (repeated 1 + 5 regimen). We collected data of 441 patients ≥ 60 years in first CR from a single institution. Median age was 67 years. Sixty-one (14%) patients received allo-HSCT, 51 (12%) auto-HSCT, 70 (16%) intensive chemotherapy with intermediate- or high-dose cytarabine (I/HDAC), and 190 (43%) 1 + 5 regimen. Median follow-up was 6.5 years. In multivariate analysis, allo-HSCT, cytogenetics, and PS had a significant impact on OS and LFS. In spite of a more favorable-risk profile, the patients who received I/HDAC had no significantly better LFS as compared with patients treated with 1 + 5 (median LFS 8.8 months vs 10.6 months, p = 0.96). In transplanted patients, median LFS was 13.3 months for auto-HSCT and 25.8 months for allo-HSCT. Pre-transplant chemotherapy with I/HDAC had no effect on the outcome. Toxicity was significantly increased for both transplanted and non-transplanted patients treated with I/HDAC, with more units of blood and platelet transfusion and more time spent in hospitalization, but no higher non-relapse mortality. This study shows that post-remission chemotherapy intensification is not associated with significantly better outcome as compared with standard-dose chemotherapy in elderly patients for whom, overall results remain disappointing. [ABSTRACT FROM AUTHOR]

A study of the trace elements distribution in sediments along the main watercourse of the Linares mining district (Jaen, Spain) was carried out. For this purpose, 56 soil samples were collected in the stream channel and floodplain. To obtain a geochemical characterisation of the soil, the pH, organic matter and the silt-clay fraction were measured and 33 elements were analysed. The results derived from these measurements were studied statistically and compared to the reference values for soils standards under two different regulations. This made it possible to recognise the dispersion patterns of the different metals and metalloids associated with the old mining activity of the district and to characterise the effects of the various pollution sources along the watercourse. An elevated Pb content was detected, which was associated with tailings ponds and waste rock dumps. Similarly, high concentrations of As in sediments were identified, which were associated with a smelter located at the headwater of the catchment area. [ABSTRACT FROM AUTHOR]

Through the confinement of gas in nanoporous materials, it is possible to significantly increase the path length for light-gas interaction. This enables the observation of much stronger absorption features for the confined gas molecules. In this work, we systematically characterized a variety of disordered strongly scattering ZrO $$_2$$ and Al $$_2$$ O $$_3$$ nanoporous ceramic materials to exploit the potential of gas in scattering media absorption spectroscopy. As a result, we identified a material with an unprecedented performance in terms of optical path length enhancement. In ZrO $$_2$$ with thicknesses above 6 mm, the path enhancement exceeds 1000. The results obtained with near-infrared absorption spectroscopy on oxygen were validated by time-of-flight measurements at 700 nm, thus demonstrating their robustness. Finally, we report quantitative oxygen concentration measurement using nanoporous materials as miniaturized random-scattering multipass cell with an extremely simple and low-cost setup. [ABSTRACT FROM AUTHOR]

Deception Island shows the most recent exposed active volcanism in the northern boundary of the Bransfield Trough. The succession of the volcanic sequence in the island is broadly divided into pre- and post-caldera collapse units although a well-constrained chronological identification of the well-defined successive volcanic episodes is still needed. A new paleomagnetic investigation was carried out on 157 samples grouped in 20 sites from the volcanic deposits of Deception Island (South Shetlands archipelago, Antarctic Peninsula region) distributed in: (1) volcanic breccia (3 sites) and lavas (2 sites) prior to the caldera collapse; (2) lavas emplaced after the caldera collapse (10 sites); and (3) dikes cutting pre- and the lowermost post-caldera collapse units (5 sites). The information revealed by paleomagnetism provides new data about the evolution of the multi-episodic volcanic edifice of this Quaternary volcano, suggesting that the present-day position of the volcanic materials is close to their original emplacement position. The new data have been combined with previous paleomagnetic results in order to tentatively propose an age when comparing the paleomagnetic data with a global geomagnetic model. Despite the uncertainties in the use of averaged paleomagnetic data per volcanic units, the new data in combination with tephra occurrences noted elsewhere in the region suggest that the pre-caldera units (F1 and F2) erupted before 12,000 year BC, the caldera collapse took place at about 8300 year BC, and post-caldera units S1 and S2 are younger than 2000 year BC. [ABSTRACT FROM AUTHOR]

A new sensing platform to simultaneously identify and quantify volatile C1 to C4 alkanes in multi-component gas mixtures is presented. This setup is based on an optically pumped, broadly tunable mid-infrared vertical-external-cavity surface-emitting laser (VECSEL) developed for gas detection. The lead-chalcogenide VECSEL is the key component of the presented optical sensor. The potential of the proposed sensing setup is illustrated by experimental absorption spectra obtained from various mixtures of volatile hydrocarbons and water vapor. The sensor has a sub-ppm limit of detection for each targeted alkane in a hydrocarbon gas mixture even in the presence of a high water vapor content. [ABSTRACT FROM AUTHOR]

The specific antiproton- and positron-beam requirements of the CERN AD-7 experiment, GBAR (Gravitational Behavior of Antimatter at Rest) are presented. GBAR will synthesize antihydrogen ions which will be sympathetically cooled before performing a free-fall experiment on the atom. Antiprotons delivered by CERN's ELENA facility in 100-keV, 300-ns pulses will be electrostatically decelerated and transformed to keV energies using a pulsed drift tube. Positrons are created using a linear electron accelerator and collected into a Penning-Malmberg trap. Descriptions of these ion optical systems are given along with the status. [ABSTRACT FROM AUTHOR]

The Einstein classical Weak Equivalence Principle states that the trajectory of a particle is independent of its composition and internal structure when it is only submitted to gravitational forces. This fundamental principle has never been directly tested with antimatter. However, theoretical models such as supergravity may contain components inducing repulsive gravity, thus violating this principle. The GBAR project (Gravitational Behaviour of Antihydrogen at Rest) proposes to measure the free fall acceleration of ultracold neutral antihydrogen atoms in the terrestrial gravitational field. The experiment consists in preparing antihydrogen ions (one antiproton and two positrons) and sympathetically cool them with Be ions to a few 10 μ K. The ultracold ions will then be photoionized just above threshold, and the free-fall time over a known distance measured. In this work, the GBAR project is described as well as possible improvements that use quantum reflection of antihydrogen on surfaces to use quantum methods of measurements. [ABSTRACT FROM AUTHOR]

Anthropogenic pressure influences the two-way interactions between shallow aquifers and coastal lagoons. Aquifer overexploitation may lead to seawater intrusion, and aquifer recharge from rainfall plus irrigation may, in turn, increase the groundwater discharge into the lagoon. We analyse the evolution, since the 1950s up to the present, of the interactions between the Campo de Cartagena Quaternary aquifer and the Mar Menor coastal lagoon (SE Spain). This is a very heterogeneous and anisotropic detrital aquifer, where aquifer-lagoon interface has a very irregular geometry. Using electrical resistivity tomography, we clearly identified the freshwater-saltwater transition zone and detected areas affected by seawater intrusion. Severity of the intrusion was spatially variable and significantly related to the density of irrigation wells in 1950s-1960s, suggesting the role of groundwater overexploitation. We distinguish two different mechanisms by which water from the sea invades the land: (a) horizontal advance of the interface due to a wide exploitation area and (b) vertical rise (upconing) caused by local intensive pumping. In general, shallow parts of the geophysical profiles show higher electrical resistivity associated with freshwater mainly coming from irrigation return flows, with water resources mostly from deep confined aquifers and imported from Tagus river, 400 km north. This indicates a likely reversal of the former seawater intrusion process. [ABSTRACT FROM AUTHOR]

A new method named photothermal diffuse reflectance (PTDR) is presented. This method combines the diffuse reflectance spectroscopy with the photothermal technique and is particularly suited for the investigation of strongly scattering samples. This method takes advantage of the high spectral selectivity and absorption of the mid-infrared region with the larger scattering cross section and high detector sensitivity available in the near-infrared. A model describing the PTDR method is proposed and supported with experimental results. The potential of the PTDR technique is illustrated by experimental signals obtained from various scattering media like polymers, liquids and powders. [ABSTRACT FROM AUTHOR]

We study the explosive expansion near the boundary of the large solutions of the equation where $${\Omega}$$ is an open bounded set of $${\mathbb{R}^{N}}$$ , N > 1, with adequately smooth boundary, m > p−1 > 0, and f is a continuous nonnegative function in $${\Omega}$$ . Roughly speaking, we show that the number of explosive terms in the asymptotic boundary expansion of the solution is finite, but it goes to infinity as m goes to p−1. For illustrative choices of the sources, we prove that the expansion consists of two possible geometrical and nongeometrical parts. For low explosive sources, the nongeometrical part does not exist, and all coefficients depend on the diffusion and the geometry of the domain. For high explosive sources, there are coefficients, relative to the nongeometrical part, independent on $${\Omega}$$ and the diffusion. In this case, the geometrical part cannot exist, and we say then that the source is very high explosive. We emphasize that low or high explosive sources can cause different geometrical properties in the expansion for a given interior structure of the differential operator. This paper is strongly motivated by the applications, in particular by the non-Newtonian fluid theory where p ≠ 2 involves rheological properties of the medium. [ABSTRACT FROM AUTHOR]

Background: Venous thromboembolism (VTE) and renal insufficiency are common in cancer patients. Prompt treatment is necessary to reduce the high rates of VTE-related mortality and morbidity. VTE prophylaxis is underused in cancer patients. We review current recommendations for the treatment and prevention of VTE in cancer patients and discuss low molecular weight heparin (LMWH) use in cases of renal failure. Design: This study is a retrospective literature review. Results: There are few published recommendations for LMWH use in cancer patients with renal insufficiency. Treatment guidelines largely follow recommendations for other patients with renal failure. Enoxaparin therapy is complicated by the need for regular monitoring of renal function and anti-Xa levels and for dosage adjustment to prevent bleeding. Few data are available to support the systematic use of dalteparin. Tinzaparin is least likely to bioaccumulate in patients with renal failure. Conclusion: VTE is the second most common cause of death in cancer patients. Renal insufficiency is present in 50-60 % of cancer patients. Data from renal patients suggest that tinzaparin may be safe and effective for VTE treatment and prevention in cancer patients with renal failure. [ABSTRACT FROM AUTHOR]

The mining exploitation of metallic sulphides, together with the activities associated to the mineral treatment and smelting, when maintained through centuries due to the wealth of the ores, generate important accumulations of wastes in structures of different kind of tailing dams and ponds, for instance. When no previous corrective steps are taken, as usually happens in old exploitations, this means a serious risk of environmental pollution, due to the mobilisation of heavy metals. The present study has been carried out in a mining district, actively exploited during the last two millennia, that was the first world's producer of lead during some periods (Linares-La Carolina, southern Spain). In this district, the mining activity was associated to a philonian network of metallic sulphurs and ended by the 1980s of the past century. The ancient mining operations, mostly subterranean, have generated large accumulations of residues without any prior corrective action. Therefore, this work intends to characterise these mining dams and determine the influence of these mining wastes on the quality of surface and ground waters. With this goal, three structures that store the mining refuse of different mineralogical origin have been selected. First, a geochemical characterisation of the soil was performed in the area surrounding each of the structures. In all cases, high levels of trace elements (including Pb, Zn, Cu, Cd, Mn, As, Sb and Ba) were observed. A hydrochemical study revealed the mobilisation through the aqueous medium of certain contaminants from the leachate of these ancient accumulations; these contaminants will flow to the streams that drain the area or to the aquifers of the sector. The internal characterisation of these structures was performed with geophysical techniques, specifically electrical resistivity imaging (ERI). The six generated resistivity models have allowed the identification of the morphology of the structures, variations in the vertical and horizontal distribution of the deposited material, fracture zones, water content and reload-unload zones and the contact of the mining wastes with the substrate. Thus, the ERI study confirms the lack of impermeabilisation measures for the terrain in the spill zones in all three cases, which indicates a high risk of contamination of the soil and waters. The obtained images also permit the identification of the ideal positions to conduct future borehole controls. [ABSTRACT FROM AUTHOR]

The simultaneous dual-frequency operation of a resonant photoacoustic gas sensor based on the differential mode excitation photoacoustic (DME-PA) technique is presented. The DME-PA method uses the excitation of two different modes in a resonant photoacoustic cell and the gas concentration is derived from the amplitude ratio of these acoustic modes. With the simultaneous dual-frequency excitation, the amplitude ratio needed by the DME-PA technique is obtained instantaneously, in contrast to the sequential modulation scheme where additional time delays are introduced by changing the modulation frequency. For a given excitation power reaching the photoacoustic cell, and a total acquisition time longer than 7 s, the simultaneous modulation scheme provides an improved measurement uncertainty compared to the sequential scheme. The proposed sensor allows measuring water vapour with a ±150 ppmV uncertainty using current-modulated near-infrared LEDs and a 15 s total acquisition time. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article on the mutation of ASXL1 gene in myeloproliferative neoplasms that was published in the July 16, 2009 issue.

The success of laser-based trace gas sensing techniques crucially depends on the availability and performance of tunable laser sources combined with appropriate detection schemes. Besides near-infrared diode lasers, continuously tunable midinfrared quantum cascade lasers and nonlinear optical laser sources are preferentially employed today. Detection schemes are based on sensitive absorption measurements and comprise direct absorption in multi-pass cells as well as photoacoustic and cavity ringdown techniques in various configurations. We illustrate the performance of several systems implemented in our laboratory. These include time-resolved multicomponent traffic emission measurements with a mobile CO2-laser photoacoustic system, a diode-laser based cavity ringdown device for measurements of impurities in industrial process control, isotope ratio measurements with a difference frequency (DFG) laser source combined with balanced path length detection, detection of methylamines for breath analysis with both a near-IR diode laser and a DFG source, and finally, acetone measurements with a heatable multipass cell intended for vapor phase studies on doping agents in urine samples. [ABSTRACT FROM AUTHOR]

The Linares region (southern Spain) has been subjected to two important sources of pollution: the intensive mining works and the urban-industrial activity. To obtain a geochemical characterisation of the soil, 31 trace elements were analysed and 669 soil samples were collected. By means of clustering analysis, we identified groups of elements and grid squares in which relations could be established concerning soil lithology, urban and industrial activities and the degree of pollution impact; in addition, we were able to characterise the geochemical background of the study area. The multivariate study led us to identify four factors. Particularly important was factor 2, which represented the elements associated with mineral paragenesis (Cu, Pb, As, Co, Mn, Zn, Sn, Ba). This factor also contains elements related with an urban-industrial activity, such as Pb, Cu, Zn, As and Ba. Furthermore, we identified factor 4, associating Ni, V and Cr, and which is related to the use of fuels. [ABSTRACT FROM AUTHOR]

The potential benefit of rituximab as adjuvant to high-dose therapy (HDT) has been investigated in patients under 60 years with poor-risk (age-adjusted international prognostic index at 2–3) CD20+ diffuse large B-cell lymphoma (DLBCL). The treatment consisted of four cycles of high-dose CEOP (cyclophosphamide, epirubicin, vincristine, prednisone), plus etoposide and cisplatin during the two last cycles. Peripheral blood stem cells were collected after cycle 1, and reinfused after cycles 3 and 4. Four weekly rituximab infusions were subsequently delivered. Among the 36 patients included, 30 could complete chemotherapy schedule, and 24/36 received rituximab. A complete response occurred in 26/36 patients (72%). With a median follow-up of 30 months, the estimated 5-year overall survival (OS) and event-free survival (EFS) rates (mean±s.d.) were 65±16 and 63±15%, respectively. For the 24 patients who received both chemotherapy and rituximab, the estimated 5-year OS and EFS rates were 86±14 and 82±15%. These data suggest that rituximab after HDT is feasible. Both complete remission rate and survival curves compare favorably with the poor outcome usually observed in high-risk DLBCL patients managed with HDT without rituximab.Bone Marrow Transplantation (2006) 38, 217–222. doi:10.1038/sj.bmt.1705414; published online 12 June 2006 [ABSTRACT FROM AUTHOR]

A series of 136 nervous system tumours were studied to determine the methylation status of the CpG island contained within the promoter region of the RB1 gene, as well as mutation analysis of the essential promoter region and exons 20-24 (and surrounding intronic regions) coding for the protein-binding pocket domain. Methylation of the RB1 CpG island was detected in 26 samples corresponding to nine glioblastomas, three anaplastic astrocytomas, one mixed oligo-astrocytoma, one ependymoma, two medulloblastomas, two primary central nervous system lymphomas, two neurofibrosarcomas, and six brain metastasis from solid tumours. No inactivating mutations were found within the RB1 promoter region, whereas one glioblastoma and one oligodendroglioma displayed similar sequence variations consisting of 12 and 8 base pair deletions at intron 21. These results suggest that RB1 CpG island hypermethylation is a common epigenetic event that is associated with the development of malignant nervous system tumours. [ABSTRACT FROM AUTHOR]

Demonstrating the vital character of an injury and estimation of the age are routine tasks in forensic pathology and although many different techniques have been applied to this problem none have been found to be completely satisfactory. Apoptosis, an active genetically controlled process, is the major mechanism by which homeostasis of a number of physiological systems in the body is regulated and changes in the rate following different kinds of stimuli have prompted us to test it as an indicator of vitality. We used an in situ end-labelling technique (Apop-Tag) in 30 human surgical skin injuries with age since injury ranging from 3 min to 8 h and found that apoptotic keratinocytes are found in over 50% of the cases with a post-infliction interval of at least 120 min. Apoptosis was not seen in injuries less than 120 min old or in normal skin, which was used as an external control. These results suggest that apoptosis could be a useful indicator for the intravital occurrence of injuries and could help to estimate the date of the skin injuries in some cases. The importance of strict technical control is stressed and the necessity of a complementary technique to confirm apoptosis is discussed. [ABSTRACT FROM AUTHOR]

Loss of heterozygosity (LOH) involving the distal chromosome 1p36 region occurs frequently in nonastrocytic brain tumours, but the tumour suppressor gene targeted by this deletion is unknown.p73 is a novel gene that has high sequence homology and similar gene structure to thep53 gene; it has been mapped to 1p36, and may thus represent a candidate for this tumour suppressor gene. To determine whetherp73 is involved in nonastrocytic brain tumour development, we analysed 65 tumour samples including 26 oligodendrogliomas, 4 ependymomas, 5 medulloblastomas, 10 meningiomas, 2 meningeal haemangiopericytomas, 2 neurofibrosarcomas, 3 primary lymphomas, 8 schwannomas and 5 metastatic tumours to the brain, forp73 alterations. Characterization of allelic loss at 1p36-p35 showed LOH in about 50% of cases, primarily involving oligodendroglial tumours (22 of 26 cases analysed; 85%) and meningiomas (4 of 10; 40%). PCR-SSCP and direct DNA sequencing of exons 2 to 14 ofp73 revealed a missense mutation in one primary lymphoma: a G-to-A transition, with Glu291Lys change. 8 additional cases displayed no tumour-specific alterations, as 3 distinct polymorphic changes were identified: a double polymorphic change of exon 5 was found in one ependymoma and both samples derived from an oligodendroglioma, as follows: a G-to-A transition with no change in Pro 146, and a C-to-T variation with no change in Asn 204: a delG at exon 3/+12 position was identified in 4 samples corresponding to 2 oligodendrogliomas, 1 ependymoma and 1 meningioma, and a C-to-T change at exon 2/+10 position was present in a metastatic tumour. Although both LOH at 1p36 andp73 sequence changes were evidenced in 4 cases, it is difficult to establish a causal role of thep73 variations and nonastrocytic brain tumours development. [ABSTRACT FROM AUTHOR]

Objective: To compare the pharmacokinetic profile of a single intravenous injection of quinupristin/dalfopristin, a new injectable streptogramin, in healthy young individuals and patients with severe chronic renal insufficiency. A secondary objective was to assess the relative tolerability of this dose in these patients compared with healthy individuals.Patients and Participants: 13 patients with severe chronic renal insufficiency (creatinine clearance 6 to 28 ml/min/1.73m2) were individually matched for gender, bodyweight and age to a healthy volunteer.Methods: Participants received a single dose of quinupristin/dalfopristin 7.5 mg/kg bodyweight as a continuous 1-hour intravenous infusion, followed by serial blood sampling.Results: The disposition profile of unchanged quinupristin was similar in the 2 groups. However, the elimination of quinupristin derivatives in patients with renal impairment tended to be decreased: mean peak plasma drug concentration (Cmax) and area under the concentration-time curve from zero to infinity (AUCinfinity) of quinupristin plus its active derivatives were about 1.4 times higher in the patients with renal impairment compared with healthy volunteers. The mean Cmax and AUCinfinity of both unchanged dalfopristin and dalfopristin plus its active derivatives were about 1.3 times higher in renally impaired patients than in healthy volunteers. Adverse events were generally mild and transient. No severe or serious adverse events were reported and no participants prematurely discontinued the study. Venous tolerability tended to be better in healthy volunteers than in the patients with renal impairment.Conclusion: These results suggest that no formal reduction in the dosage of quinupristin/dalfopristin is necessary in patients with severe chronic renal impairment. [ABSTRACT FROM AUTHOR]

A significant proportion of post-menopausal, patients treated with AI reports side-effects, especially bone pain. In such patients, the difficulties to treat pain and to clearly identify its causes may lead to treatment discontinuation. Ageing is associated with physiological modifications that may impair drug pharmacokinetics (PKs). The elimination can be altered, with decreased drug clearance (CL), resulting in an increased exposure to the drug, reflected by increased AUCs. The reported increases in AI exposure being around 50 %, an intermittent dosing schedule of 1 administration every other day could result in a similar drug exposure as compared to the usual daily schedule. [ABSTRACT FROM AUTHOR]

Abstract Adolescents (N=38) who attended a multi modal day program were matched with a control group (N=35) for age, gender, year of assessment, and on delinquent and aggressive scores. Parent and child were separately interviewed three years after initial assessment. Adolescents who attended the program functioned better overall and were more satisfied with treatment than controls. Both groups showed a poor outcome and a decrease in symptom scores. A diagnosis of conduct disorder, high delinquency scores and high total problem scores predicted a poorer outcome. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Adult and fourth-stage larvae of Paracuaria hispanica n. sp., from the stomach of the Pyrenean desman Galemys pyrenaicus Geoffroy (Insectivora: Talpidae) in northern and central Spain, are described. The new species differs from the other members of the genus Paracuaria ( P. adunca and P. soricis), among other morphological details, in its smaller body and spicule sizes, the presence of a cuticular ring around the tip of the female tail, and the existence of lateral alae running longitudinally along its body from the cervical region to the tail. In view of the latter feature, the genus Paracuaria is redefined. The fourth stage larva of the new species is distinguished from that of P. adunca by its monocuspid deirids. P. hispanica occurred in 45% of the 20 host specimens examined. [ABSTRACT FROM AUTHOR]

In this paper we study initial value problems like u−R¦▽u¦+λu=0 in ℝ× ℝ, u(·,0)=u(·) in ℝ, where R > 0, 0 < q < 1, m ≥ 1, and u is a positive uniformly continuous function verifying − R¦▽u¦+λu⩾ 0 in ℝ. We show the existence of the minimum nonnegative continuous viscosity solution u, as well as the existence of the function t(·) defined by u(x, t) > 0 if 0< t< t( x) and u(x, t)=0 if t ≥ t(x). Regularity, extinction rate, and asymptotic behavior of t(x) are also studied. Moreover, for m=1 we obtain the representation formula u(x, t)=max{([( u(x − ξt)) − λ(1−q)t]): ¦ξ¦≤ R}, ( x, t)εℝ. [ABSTRACT FROM AUTHOR]

We present a family, identified through a girl with 'Cri-du-chat syndrome', in which two different types of recombinants exist [del(5)(qter→p14:) and dup(5)(p13)]. They are due to a 5p paracentric inversion of maternal origin [inv(5) (pter p13)]. We discuss the relationship between the breakpoints and segregation of the inversion carrier, as well as the origin and the identification of the recombinants. [ABSTRACT FROM AUTHOR]

Describes developmental issues that pose current challenges to the design of treatment outcome investigation with children and adolescents. Normal childhood development and the development of childhood disorders are discussed using the transactional model of development. Challenges in diagnostic decision making, the selection of the most appropriate treatment regimen, and the measurement methods are highlighted. Recognition of the need to study child treatments through long-term follow-up periods underscores the need for resolution of these developmental issues. [ABSTRACT FROM AUTHOR]

Copyright of International Orthopaedics is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: The first goal of phase I drug development is the determination of maximal tolerated dose, which must be established by case-by-case analysis, sometimes using a laboratory adverse event. Since no accurate rule defining lab adverse events, has been validated yet, we propose a new “combined method” based on combination of two thresholds: inclusion values and magnitude of variation. Using this combined method, the label “lab adverse event” is applied if any lab value exceeds the inclusion threshold and is associated with a variation from baseline exceeding the variation threshold defined from reference change limit. Thus, this study aimed to test this combined method on a large healthy volunteer population, studied in 19 phase I centres worldwide, and on five lab parameters: alanine amino transferase, aspartate amino transferase, alkaline phosphatases, creatinine and polymorphonuclear leukocytes. Methods: The inclusion threshold from each center was used. Reference change limits were defined from volunteers previously included in comparable studies and were expressed as absolute values: increases of 10 IU · l−1 for alanine amino transferase or aspartate amino transferase, 15 IU · l−1 for alkaline phosphatases, 15 μmol · l−1 for creatinine and a 0.34 109 · l−1 decrease for polymorphonuclear leukocytes. Comparison between the “combined method” and a normal range method was made using positive predictive value and a ratio between relevant and irrelevant results. This application was implemented in all young healthy volunteers (1134) included in 38 phase I studies sponsored by Rhône Poulenc Rorer from 1991 to 1993. Results: Seventy seven subjects (6.7%) were indicated in final study reports as having a lab adverse event (reference group). Of 179 subjects with lab abnormalities defined by the normal range method, 77 belonged to the reference group, inducing a poor 0.43 positive predictive value. Of ninety subjects with lab adverse events defined by the “combined method”, seventy-five belonged to the reference group, inducing a two-fold higher 0.83 positive predictive value. The combined method produced a high ratio of relevant/irrelevant results ( ) compared with the low ratio ( ) achieved using the normal range method. Conclusion: This new “combined method”, leading to a better definition of lab adverse event, seems an accurate and useful tool for routine case-by-case analysis within phase I drug development studies. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Animal Health & Production is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extracellular recordings were performed in the nucleus of the basal optic root (nBOR) of alert pigeons during optokinetic nystagmus (OKN), vestibulo-ocular reflex (VOR) and combined visuo-vestibular stimulation. Cell identification was assessed either by histological control or by electrophysiological testing (antidromic response to vestibulo-cerebellar or oculomotor complex stimulation). 1) OKN was induced in 8 directions by a binocular stimulation. During the fast phase of OKN, optokinetic after nystagmus (OKAN) or reversed OKAN, most cells showed an inhibition which varied in magnitude independent of the direction of stimulation. A few cells however showed a phasic discharge for some OKN directions. 2) During the slow phase of OKN induced by a binocular stimulation, cells displayed either a tonic activation or a more or less strong inhibition according to the direction of the OKN. Cells were classified in 4 groups, according to their degree of directional specificity. The best OKN direction (slow phase) for maximal cell activation was upwards and naso-upwards, and next to best, nasotemporal and downwards. Maximal cell inhibition occurred during downward, and for some cells during upward, directions. 3) During OKN induced by stimulating the eye contralateral to the recorded nBOR, cell responses resembled those obtained during binocular stimulation, but, during ipsilaterally induced OKN, the cells lost their directional specificity. As a result of binocular integration, neuronal activation seems to originate from contralateral input whereas cell inhibition would mainly come from ipsilateral input. 4) During sinusoidal optokinetic stimulation induced in the temporo downward-naso upward axis, cells showed a more or less marked modulation (according to their directional selectivity) that was closely in phase with the stimulation velocity, and therefore probably with retinal slip. 5) nBOR cells appeared generally unaffected during both the slow phase and the fast phase of the VOR. However, some cells showed a slight but irregular modulation which might imply a weak vestibular input. During visuo-vestibular stimulation, the response resembled that obtained with sinusoidal optokinetic stimulation but the fast phase inhibition was often strengthened in the downwards direction (fast phase). [ABSTRACT FROM AUTHOR]

The accessory optic system (AOS) in birds is composed of two structures: the nucleus Superficialis Synencephali (nSS), essential for the production of an optokinetic nystagmus (OKN) in the temporo-nasal direction (slow phase) for the eye contralateral to the nucleus, and the nucleus Ectomamillaris (nEM), or nucleus of the basal optic root (nBOR). The objectives of the present work were: (1) to study the importance of the nEM for the horizontal OKN, (2) to study the interactions between the nSS and the nEM. Experiments were realized by combining different kinds of lesion. The role of the nuclei of the AOS in birds is discussed in terms of existing anatomical and physiological data. [ABSTRACT FROM AUTHOR]

In birds, the accessory optic system (AOS) includes two nuclei: the nucleus ectomamillaris (nEM) and the pretectal nucleus superficialis synencephali (nSS). The role of the nSS in the production of a horizontal optokinetic nystagmus (OKN) was studied in the pigeon, by comparing the OKN before and after a unilateral lesion of this nucleus. The lesions were performed either by electrolysis or by local application of kainic acid (KA); the KA lesions gave more stable modifications of the OKN than the electrolytic lesions. A quantitative analysis of the slow-phase velocity (¯V) of the OKN was carried out on the animals receiving KA lesions. The anatomical and physiological data so far available consistently support the hypothesis of a functional equivalence between the nSS in birds and the nucleus of the optic tract in mammals. [ABSTRACT FROM AUTHOR]

A study of optokinetic nystagmus (OKN) as produced by monocular or binocular stimulation was carried out in the pigeon. Nystagmus was provoked by constant speed rotation (13 or 36 °/s) of an optokinetic drum lined with alternate black and white vertical stripes. With the animal's head immobilized, the electro-oculogram of each eye was recorded for both directions of rotation. The pigeon OKN was compared to that of other species, leading us to propose a correlation between the symmetrical or asymmetrical character of the nystagmus and the frontal or more or less lateral position of the eyes. [ABSTRACT FROM AUTHOR]

The stratal architecture of the Gulf of Cádiz continental margin (SW Spain) has been analyzed by using single-channel, very high-resolution seismic reflection profiles. An evolutionary scheme of asymmetrical depositional sequences is proposed that was governed by the Late Pleistocene–Holocene sea-level fluctuations. Stratigraphic analysis defined 14 seismic units, that are configured into two major type-1 depositional sequences related to 4th-order eustatic sea level changes (100–110 ka). Within these sequences, minor asymmetrical depositional sequences have been recognized related to 5th-order eustatic cycles (22–23 ka) superimposed and modulated by the regressive trends of 4th-order cycles. In 5th-order depositional sequences, the forced regressive and lowstand deposits are volumetrically dominant. They cause the main progradation of the margin in such a way that they form the margin structure almost entirely. [ABSTRACT FROM AUTHOR]

On the basis of the correlation between seismic tectonostratigraphic units, volcanism, and geochemical distribution patterns of sea-floor sediments on Deception Island (Antarctica), a regional tectonic extension is suggested to explain the sequence of volcanic and hydrothermal events. The syncollapse caldera episode is composed of five tectonostratigraphic units separated by progressively tilted and bent unconformities. Each unit shows a sequence of Quaternary volcanic cones and mound structures that display high contents of Fe, Mn, and Zn. As-rich active fumaroles and hot-spring areas are associated with the postcollapse episode and linked to normal faulting and present volcanism. [ABSTRACT FROM AUTHOR]

The specificity of three HIV EIAs using synthetic peptides was evaluated and compared with that of four commercial EIAs using recombinant proteins or whole virus lysates of HIV-1 or of HIV-1 and HIV-2, and of two tests based on agglutination of sensitized particles. A total of 734 West African sera were screened. The best results were obtained with tests using recombinant proteins. HIV tests using synthetic peptides able to distinguish between HIV-1 and HIV-2 antibodies showed comparable specificity, but some false negative results represent a major handicap of these peptide EIAs in screening for HIV antibodies. [ABSTRACT FROM AUTHOR]

This paper analyzes the scientific relationships between Spain and the Eastern European countries (EEc), including the former USSR, from 1982 to 1992. The study considers the number of co-authored papers as well as the number of stays which reflect to the exchange of scientists among them. The total number of co-authored papers of Spanish scientists with their colleagues of those countries is 664 as recorded in the Science Citation Index. During the last three years, a significative increase in the number of co-signed papers has been observed. From the sample considered, the percentage of bilateral and multilateral co-authored papers is 43.8 and 56.2 respectively. In absolute figures, USSR and Poland are the countries with highest number of collaborative papers with Spain. However, in relation to their scientific output, Poland and Hungary show a higher percentage of co-authored papers than the rest of EEc. On the other hand, previous data, provided by the Spanish Secretary of State for Research and Universities (SEUI), related to the flow of scientists on sabbatical year to and from Spain, showed that from 1984 to 1994, a total of 213 researches come from the EEc to Spain, while the number of Spanish scientists going to those countries was extremely scarce. [ABSTRACT FROM AUTHOR]