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Isla Santa Cruz is a volcanic island located in the central Galápagos Archipelago. The island's northern and southern flanks are deformed by E–W-trending normal faults not observed on the younger Galápagos shields, and Santa Cruz lacks the large summit calderas that characterize those structures. To construct a chronology of volcanism and deformation on Santa Cruz, we employ 40Ar/39Ar geochronology of lavas and 3He exposure dating of fault scarps from across the island. The combination of Ar–Ar dating with in situ-produced cosmogenic exposure age data provides a powerful tool to evaluate fault chronologies. The 40Ar/39Ar ages indicate that the island has been volcanically active since at least 1.62 ± 0.030 Ma (2SD). Volcanism deposited lavas over the entire island until ~ 200 ka, when it became focused along an E–W-trending summit vent system; all dated lavas < 200 ka were emplaced on the southern flank. Structural observations suggest that the island has experienced two major faulting episodes. Crosscutting relationships of lavas indicate that north flank faults formed after 1.16 ± 0.070 Ma, but likely before 416 ± 36 ka, whereas the faults on the southern flank of the island initiated between 201 ± 37 and 32.6 ± 4.6 ka, based on 3He exposure dating of fault surfaces. The data are consistent with a model wherein the northeastern faults are associated with regional extension owing to the young volcano's location closer to the Galápagos Spreading Center at the time. The second phase of volcanism is contemporaneous with the formation of the southern faults. The expression of this younger, low-volume volcanic phase was likely related to the elongate island morphology established during earlier deformation. The complex feedback between tectonic and volcanic processes responsible for southward spreading along the southern flank likely generated persistent E-W-oriented magmatic intrusions. The formation of the Galápagos Transform Fault and sea-level fluctuations may be the primary causes of eruptive and deformational episodes on Santa Cruz. [ABSTRACT FROM AUTHOR]

We report the detection of extended X-ray emission from two high-redshift radio quasars. These quasars, J1405+0415 at z = 3.208 and J1610+1811 at z = 3.118, were observed in a Chandra snapshot survey selected from a complete sample of the radio-brightest quasars in the overlap area of the VLA-FIRST radio survey and the Sloan Digital Sky Survey. The extended X-ray emission is located along the line connecting the core to a radio knot or hotspot, favoring the interpretation of X-ray jets. The inferred rest-frame jet X-ray luminosities from 2 to 30 keV would be of order 1045 erg s−1 if emitted isotropically and without relativistic beaming. In the scenario of inverse Compton scattering of the cosmic microwave background (CMB), X-ray jets without a coincident radio counterpart may be common, and should be readily detectable to redshifts even beyond 3.2 due to the (1+z)4 increase of the CMB energy density compensating for the (1+z)−4 cosmological diminution of surface brightness. If these can be X-ray confirmed, they would be the second and third examples of quasar X-ray jets without detection of underlying continuous radio jets. [ABSTRACT FROM AUTHOR]

The rise in carbapenem resistance among Gram-negative bacteria has renewed interest in colistin. Recently, the EUCAST-CLSI Polymyxin Breakpoints Working Group declared that broth microdilution (BMD) is the only valid method for colistin susceptibility testing. BMD is not easily incorporated into the routine work of clinical laboratories, and usually this test is incorporated serially, resulting in delayed susceptibility reporting. We tested a strategy of combining VITEK® 2 with a 2 μg/mL colistin agar dilution (VITEK® 2/AD) screening plate to improve performance and time to reporting of colistin susceptibility. Colistin susceptibility for 364 clinical isolates was determined by VITEK® 2/AD and compared with the reference standard BMD according to the ISO 20776-1:2007 and CLSI guidelines. The EUCAST colistin susceptibility breakpoint of ≤2 μg/mL was used. Escherichia coli NCTC 13846 served as quality control strain. Agreement, very major error (VME) and major error rates were determined using ISO 20776-2:2007. The VME rate for VITEK® 2 alone was 30.6% (15/49, 95% CI 18.3–45.4%), and was reduced to 10.2% (5/49, 95% CI 3.4–22.2%) using the VITEK® 2/AD combined testing. The combined testing had categorical agreement with BMD of 97% (354/364, 95% CI 95.0–98.7%), and a major error (ME) rate of 1.6% (5/315, 95% CI 0.5–3.7%). Using the combined testing, even against challenging strains, 349 (95.8%, 95% CI 93.3–97.7%) colistin susceptibility results could be reported, and only 15 isolates required further analysis by BMD. Our method is simple to apply and allows rapid reporting of colistin susceptibility. [ABSTRACT FROM AUTHOR]

The structure of the fully relaxed phases of a Langmuir monolayer of tetracosanoic acid is determined by x-ray diffraction and reflection along an isotherm at ∼20.5 °C. Isotherms taken by allowing the surface pressure to stabilize between incremental compressions are seen to be qualitatively different from the constant-rate nonrelaxed isotherms typically seen in the literature. At low densities the monolayer consists of an inhomogeneous film of islands of a crystalline (or hexatic) phase with molecular tilt ordering that is analogous to that of the smectic I liquid crystal. Small amounts of impurities (∼0.5% of the monolayer) account for the change in surface pressure with area in this region. Upon compression to the point that the free space between islands becomes negligible the film appears homogeneous. On further compression the time required for full relaxation becomes long (i.e., ∼ hours), the tilt angle of the molecular axis decreases and the x-ray unit cell is compressed. Including this homogeneous I phase the phase sequence observed by diffraction upon compression is I-U-I-U, where U refers to an untilted orthorhombic phase. The outer two phases of this sequence are pure phases which form homogeneous monolayers, but the inner two are inhomogeneous phases each coexisting with an amorphous phase that does not have an observable diffraction signal. At the boundaries demarcating the I and U phases, a phase whose tilt ordering is analogous to that of a smectic F phase is seen to coexist. The preceding phase sequence is sensitive to the degree of relaxation permitted the monolayer after an incremental compression. In particular, if the monolayer is not allowed to relax completely after each compression, the untilted U phase may never appear. The UI transition is shown to be reversible for a relaxed monolayer. [ABSTRACT FROM AUTHOR]

Background Mean platelet volume ( MPV) and plateletcrit ( PCT) are indices used in evaluating immune-mediated thrombocytopenia ( IMT) in humans and in dogs with congenital macrothrombocytopenia. These indices may provide clinically valuable information in acquired thrombocytopenia. Hypothesis/Objectives Dogs with presumed primary IMT will have increased MPV, and therefore platelet mass ( PCT) will increase faster than platelet count ( PLT) during recovery. Animals Forty-nine dogs with automated PLT < 30,000/μL because of presumed primary IMT and hematocrit ( HCT), PCT, MPV, and platelet distribution width determined from the same complete blood count ( CBC), and 46 healthy controls. Methods Case-control retrospective study; PLT, PCT, MPV, and platelet distribution width ( PDW) were recorded from CBCs from 49 dogs, with 45 having data collected on the day of presentation. Fifteen were confirmed to have attained a PLT ≥ 75,000/μL on at least 1 CBC within 15 days after admission. The PCT equivalent to a PLT of 75,000/μL (assuming an average MPV) was calculated for comparison with PLT in terms of time to achieve a threshold of platelet mass by the 2 measures. Results Mean platelet volume was higher in IMT dogs (17.3 fl) than the reference population (10.5 fl) ( P < .0001). The PDW was not significantly different among the groups. The median time for PCT to reach threshold in confirmed responders was faster (3 days) compared with PLT (4 days). Conclusions and Clinical Importance Immune-mediated thrombocytopenia is characterized by increased MPV. Time to achieve a threshold PCT tended to be shorter than PLT, suggesting that PCT may be a useful platelet parameter for monitoring dogs with IMT. [ABSTRACT FROM AUTHOR]

Background:Obesity, a major risk factor for cardiometabolic disease, is associated with lower cognitive performance from childhood to senescence, especially on tasks of executive function. In the cardiovascular domain, fat stored viscerally rather than elsewhere in the body carries particularly high risk. It is unknown whether this is also true in case of obesity-cognition relationships. The aim of this study was to assess the cross-sectional relationship between visceral fat (VF) and cognitive performance in a community sample of healthy adolescents.Methods:In a community-based sample of 983 adolescents (12-18 years old, 480 males), VF was quantified using magnetic resonance imaging, total body fat was measured using a multifrequency bioimpedance, and cognitive performance was assessed using a battery of cognitive tests measuring executive function and memory.Results:We found that larger volumes of VF were associated with lower performance on six measures of executive function (P=0.0001-0.02). We also found that the association of VF with executive function was moderated by sex for a subset of measures, such that relationship was present mainly in female subjects and not in male subjects (sex-by-VF interaction: P=0.001-0.04). These relationships were independent of the quantity of total body fat and a number of potential confounders, including age, puberty stage and household income.Conclusions:Our results suggest that the adverse association between obesity and executive function may be attributed to fat stored viscerally and not to fat stored elsewhere in the body. They also suggest that female subjects compared with male subjects may be more sensitive to the potentially detrimental effects of VF on cognition. [ABSTRACT FROM AUTHOR]

Microbiological surveillance for detection of carbapenem-resistant A. baumannii is important, but recovery of A. baumannii is inadequate. We studied A. baumannii recovery by a particular transport system that is possibly superior over standard swabs, using reference and clinical strains. First, the recovery rates relating to the various swabs were compared with regard to various combinations of transport times (0 h, 1 h, 24 h, 48 h), storage times (0 weeks, 1 week, 2 weeks, 4 weeks) and storage temperatures (4°c,−80°c) using live counts. Second, the recovery of different inocula of strains mixed with fecal microbiota was evaluated by plating on selective medium. The new transport system exhibited a decline of <3log under almost all conditions studied and performed better than standard swabs under several conditions. If plated on selective media, the new transport system performed well, even after prolonged transport or with a low inoculum, and its processing could be delayed by up to 2 weeks, especially if refrigerated. The new transport system may thus enhance A. baumannii surveillance. [ABSTRACT FROM AUTHOR]

The article discusses the significance of environmental health research and genomic research. It is said that focusing on the genetic and environmental contributions to etiology and pathogenesis is crucial for understanding many specific pathophysiologic processes. The functional homology of different regulatory genes can be used to determine a comparative genomics approach species using microarray analysis and bioinformatics approaches.

All too often individuals with disabilities in the popular media are portrayed as people to be pitied or super humans to be admired. Film is one important resource that helps form the public's beliefs and dispositions about people with disabilities. With that in mind a film festival was designed to provide authentic representation of people with disabilities living normal lives so as to help viewers see individuals with disabilities as people first. Part of the effort was to develop a more realistic understanding and appreciation for the lives of individuals with disabilities. Various programs were developed across disciplines to present a wide range of perspectives. Following each viewing filmmakers and faculty led in-depth discussions about the films. A participant survey indicated the use of film as an effective pedagogical methodology that provided an entertaining and meaningful way to generate discussion and change attitudes about disabilities. [ABSTRACT FROM AUTHOR]

We summarize a study of PKS 0920-397 using our 42 ks Chandra observation in conjunction with our ATCA 20GHz image, and HST/ACS F814W and F475W images. We investigate the hypothesis that the jet X–ray emission is due to inverse-Compton (IC) scattering on the cosmic microwave background (CMB) from the same population of relativistic electrons that give rise to the radio emission. To calculate parameters intrinsic to the source, one must finesse the fact that we do not know the true angle of the jet to our line of sight. Typical assumptions are that the Doppler factor equals the bulk Lorentz factor, or that the Lorentz factor takes some fixed numerical value. While giving useful estimates, neither assumption can be exact in general. We try different constraints to determine the jet quantities. It is plausible that the kinetic flux is constant along the jet, prior to a terminal hotspot or lobe, and with minimal bending of the jet. Alternatively, because PKS 0920-397 appears straight in projection on the sky, we might assume the jet maintains a constant angle to our line of sight. Either approach gives bulk Lorentz factors of 6 to 8, with kinetic energy flux of order 1046 erg s-1, and with the jet at an angle 2° to 4° from our line of sight. [ABSTRACT FROM AUTHOR]

The absorbance of near-infrared (NIR) radiation by plants depends on the overtones of vibration, bending and stretching of the chemical bonds within their organic components. The wide variety of these bonds gives rise to characteristic NIR spectra, or ‘fingerprints’, of plant materials. Do these fingerprints remain in the soil when the plants decompose and allow discrimination between soils that have supported different types of vegetation? We have compared the NIR spectra of grassland soil with those of soil under forest in the Vosges mountains in France. Near-infrared reflectances, R, from 370 samples of soil were recorded as A = log10(1/R) at wavelengths between 1100 and 2500 nm and averaged over 10-nm intervals to give spectra each with 140 values. A canonical variate analysis (CVA) of the raw spectra discriminated well, but not perfectly, between grassland and forest soil, with Mahalanobis distance, D, of 4.87. Standardization along the spectra to remove effects of varied mineral composition achieved complete separation between the two sources with D = 9.81. Canonical variate analysis of first and second derivatives of the spectra distinguished the two groups even better, with D = 12.27 and D = 16.65, respectively. The results show much promise for inferring past vegetative cover from NIR spectra deriving from the organic matter in the soil. The next step will be to extend these studies to see how well we can distinguish other types of vegetation from such spectra. [ABSTRACT FROM AUTHOR]

DNA hybridization plays a central role in biology and, increasingly, in materials science. Yet, there is no precedent for examining the pathways by which specific single-stranded DNA sequences interact to assemble into a double helix. A detailed model of DNA is adopted in this work to examine such pathways and to determine the role of sequence, if any, on DNA hybridization. Transition path sampling simulations reveal that DNA rehybridization is prompted by a distinct nucleation event involving molecular sites with approximately four bases pairing with partners slightly offset from those involved in ideal duplexation. Nucleation is promoted in regions with repetitive base pair sequence motifs, which yield multiple possibilities for finding complementary base partners. Repetitive sequences follow a nonspecific pathway to renaturation consistent with a molecular "slithering" mechanism, whereas random sequences favor a restrictive pathway involving the formation of key base pairs before renaturation fully ensues. [ABSTRACT FROM AUTHOR]

Unlabelled: The second Lebanon war started as a limited operation and progressed to a large-scale campaign. Most of the fighting took place in mountainous villages and small towns inhabited with civilians. The Israeli Defense Forces (IDF) Airborne rescue and evacuation unit is charged with air evacuation of soldiers and civilians in times of peace, limited conflict, and war.Objective: We describe this unit's activities in the second Lebanon war, analyzing injury, treatment, and evacuation characteristicsMethods: Data were collected from flight medical reports, debriefings of aero-medical team members (usually immediately upon return from mission), ground units medical reports and debriefings, and hospital records.Results: 725 IDF soldiers were injured and 117 killed either in Lebanon or near the Israeli-Lebanese border during the war. A total of 338 (46%) were evacuated in 95 airlifts (averaging 4.5 evacuees per airlift) from the fighting zones or the border. Air evacuation used dedicated helicopters with advanced care capacities, and most victims were evacuated straight from the battlefield, as the fighting was ensuing. Many wounded first received advanced medical care upon the arrival of the aero-medical teams.Conclusions: In military operations within civilian populated areas with threats to ground transport, air evacuation can sometimes be the only readily available option. Providing timely ground advanced medical care proved difficult in many instances. Thus, for many, the rescue helicopter was the first point of access to such care. Aero-medical aircrafts and personnel faced threats from gunfire and missiles, causing both delays in evacuation and a high average number of evacuees per airlift. This article proposes ways of coping with situations in which similar rescue and evacuation problems are likely. [ABSTRACT FROM AUTHOR]

Aeromedical (AM) evacuation of trauma victims from action is an integral part of trauma care. The Israeli Air Force Rescue and Evacuation Unit is responsible for nearly all AM evacuations in Israel. We present three recent cases, within 1 year of operation, of engagement process failure during evacuations performed by the Rescue and Evacuation Unit. We then discuss possible pitfalls and lessons learned. In sum, we reveal that successful AM and ground crew engagement can save lives, as long as the engagement process is as short and efficient as possible. [ABSTRACT FROM AUTHOR]

Objective: To present a case of severe interstitial nephritis with proteinuria in primary Sjögren's syndrome (pSS) and review the literature regarding renal disease and its management in pSS, aiming to suggest recommendations for treatment. Methods: A search of MEDLINE (PubMed) was performed for review articles and case reports using the MESH terms: Sjögren syndrome; renal disease; interstitial nephritis (IN); glomerulonephritis (GN). Results: We describe a rare case of pSS presenting with hypokalaemic tetraparesis and proteinuria due to severe IN, successfully treated with high-dose steroids and azathioprine. Reviewing the literature, we identified 180 reported cases of renal involvement in pSS (selected based on the European criteria for pSS), 89 of which underwent renal biopsies revealing IN in 49 cases, GN in 33 samples, and both IN and GN in seven. Eighteen studies reported treatment experience of renal disease in 32 pSS cases. Seventeen patients were treated with corticosteroids and cyclophosphamide, and 15 patients received only steroids with improvement in the majority of cases. Conclusion: The present case, as well as the limited number of reports in the literature, suggest that renal involvement, including IN, in pSS may improve with immunosuppressive therapy. Further studies are required to determine indications for and dosages of immunosuppressive treatment in patients with renal involvement of pSS. [ABSTRACT FROM AUTHOR]

Background: A broad range of pharmacologic therapies are available to treat active inflammatory bowel disease (IBD), including 5-aminosalicylate preparations, corticosteroids, and immunosuppressants (e.g., azathio prine/6-mercaptopurine [AZA/6-MP] or methotrexate). Although these therapies are effective, up to 60% of patients are refractory or intolerant. Biologic therapies, such as the anti-TNF agent infliximab, offer promise but are not without controversy; despite many positive reports, steroid-refractory patients are less likely than other individuals to respond to infliximab. Effective, long-term therapies that do not add to the adverse-effects burden in patients with IBD are needed. Of these, granulocyte/monocyte apheresis (GMA) is one promising approach.Scope: PubMed and relevant congresses databases were searched using the terms 'granulocyte/monocyte apheresis,' 'GMA,' 'leukocytapheresis,' 'Adacolumn,' and 'Cellsorba.' These studies were further selected to include only those focusing on IBD. A time frame of 2000-2006 was used.Findings: Data from open-label trials show that patients with moderate-to-severe IBD refractory to conventional pharmacologic treatment achieved clinical response and/or remission after treatment with GMA. Furthermore, recent small open-label trials of GMA show increased rates of induction and maintenance of response/remission in steroid-naïve IBD patients.Conclusions: The remission rates seen in these open-label clinical trials of GMA are consistent with those of currently available pharmacologic therapies for IBD. However, the majority of these trials enrolled only small numbers of patients, were largely open-label, and were of limited duration. These data must be confirmed in well-controlled, large-scale clinical trials. [ABSTRACT FROM AUTHOR]

We present a Chandra image of the quasar, jet, and lobes of PKS 1354+195 (=4C 19.44). The radio jet is 18 arcsec long, and appears to be very straight. The length gives many independent spatial resolution elements in the Chandra image while the straightness implies that the geometrical factors are constant along the jet although their values are uncertain. We also have 4 frequency radio images with half to one arcsecond angular resolution, and use HST and Spitzer data to study the broad band spectral energy distributions. The X-ray and radio spectra are both consistent with a spectrum f ν ∝ ν −0.7 for the integrated jet. Using that spectral index, the model of inverse Compton scattering of electrons on the cosmic microwave background (IC/CMB) gives magnetic field strengths and Doppler factors that are relatively constant along the jet. Extended X-ray emission is evident in the direction of the otherwise unseen counter-jet. X-ray emission continues past the radio jet to the South, and is detected within both the southern and northern radio lobes. [ABSTRACT FROM AUTHOR]

The Denali fault is the principal intracontinental strike-slip fault accommodating deformation of interior Alaska associated with the Yakutat plate convergence. We obtained the first quantitative late Pleistocene-Holocene slip rates on the Denali fault system from dating offset geomorphic features. Analysis of cosmogenic 10Be concentrations in boulders (n = 27) and sediment (n = 13) collected at seven sites, offset 25–170 m by the Denali and Totschunda faults, gives average ages that range from 2.4 ± 0.3 ka to 17.0 ± 1.8 ka. These offsets and ages yield late Pleistocene-Holocene average slip rates of 9.4 ± 1.6, 12.1 ± 1.7, and 8.4 ± 2.2 mm/yr-1 along the western, central, and eastern Denali fault, respectively, and 6.0 ± 1.2 mm/yr-1 along the Totschunda fault. Our results suggest a westward decrease in the mean Pleistocene-Holocene slip rate. This westward decrease likely results from partitioning of slip from the Denali fault system to thrust faults to the north and west. [ABSTRACT FROM AUTHOR]

Analysis of cosmogenic 10Be and 26Al in samples collected from exposed boulders (n = 20) and from buried sediment (n = 3) from offset fans along the San Andreas fault near Little Rock, California, yielded ages, ranging from 16 to 413 ka, which increase with distance from their source at the mouth of Little Rock Creek. In order to determine the age of the relatively younger fans, the erosion rate of the boulders and the cosmogenic nuclide inheritance from exposure prior to deposition in the fan were established. Cosmogenic nuclide inheritance values that range between 8.5 × 10³ and 196 × 10³ atoms 10Be g-1 quartz were determined by measuring the concentrations and ratios of 10Be and 26Al in boulders (n = 10) and fine sediment (n = 7) at the outlet of the present active stream. Boulder erosion rate, ranging between 17 and 160 mm k.y.-1, was estimated by measuring 10Be and 26Al concentrations in nearby bedrock outcrops (n = 8). Since the boulders on the fans represent the most resistant rocks in this environment, we used the lowest rate for the age calculations. Monte Carlo simulations were used to determine ages of 16 ± 5 and 29 ± 7 ka for the two younger fan surfaces. Older fans (older than 100 ka) were dated by analyzing 10Be and 26Al concentrations in buried sand samples. The ages of the three oldest fans range between 227 ± 242 and 413 ± 185 ka. Although fan age determinations are accompanied by large uncertainties, the results of this study show a clear trend of increasing fan ages with increasing distance from the source near Little Rock Creek and provide a long-term slip rate along this section of the San Andreas fault. Slip rate along the Mojave section of the San Andreas fault for the past 413 k.y. can be determined in several ways. The average slip rate calculated from the individual fan ages is 4.2 ± 0.9 cm yr-1. A linear regression through the data points implies a slip rate of 3.7 ± 1.0 cm yr-1. A most probable slip rate of 3.0 ± 1.0 cm yr-1 is determined by using a χ² test. These rates suggest that the average slip along the Mojave section of the San Andreas fault has been relatively constant over this time period. The slip rate along the Mojave section of the San Andreas fault, determined in this study, agrees well with previous slip rate calculations for the Quaternary. [ABSTRACT FROM AUTHOR]

Protoporphyrin IX (PpIX) synthesis by malignant cells is clinically exploited for photodiagnosis and photodynamic therapy following administration of 5-aminolevulinic acid (ALA). The expression and activity of the housekeeping porphobilinogen deaminase (PBGD) was correlated to PpIX synthesis in differentiating B16 melanoma cells. Differentiation was stimulated by two inducers, butyrate and hexamethylene bisacetamide (HMBA), both of which promote the formation of typical melanosomes and melanin, as well as morphological changeover. A marked decrease in total PBGD activity and PpIX synthesis was observed following stimulation by butyrate, while HMBA induced an opposite effect. In contrast, ferrochelatase levels remained unchanged. Photodynamic inactivation of the cells undergoing differentiation was largely dependent on the PpIX accumulation, which was modulated by the two inducers butyrate and HMBA. Fluorescence immunostaining with anti-PBGD antibodies revealed a major PBGD fraction in the nucleus and a minor fraction in the cytosol. This nuclear localisation pattern was confirmed by expression of PBGD fused to green fluorescence protein. We suggest that efficient photodynamic therapy of cancer facilitated by ALA administration can be enhanced using combined therapeutic modalities.British Journal of Cancer (2004) 90, 1833-1841. doi:10.1038/sj.bjc.6601760 www.bjcancer.com Published online 6 April 2004 [ABSTRACT FROM AUTHOR]

Perianal fistulas are a frequent manifestation of Crohn's disease. The correct application of the newer diagnostic and therapeutic agents for treating perianal Crohn's disease are beginning to be better defined. In general, a combined medical and surgical approach is preferred. The perianal disease process should first be fully delineated with endoscopy and either MRI or EUS before treatment is begun. Patients are then stratified into one of three groups: simple fistulas and no proctitis; simple fistulas and concomitant proctitis; and complex fistulas. Patients with simple fistulas and no proctitis can be treated medically with a combination of antibiotics and an immunosuppressive agent (azathioprine or mercaptopurine). Patients with simple fistulas and concomitant proctitis should have infliximab added to their treatment plan. Complex fistulas require surgical intervention first prior to medical treatment. A combination of antibiotics, immunosuppressive therapy and infliximab are then initiated to facilitate fistula healing. [ABSTRACT FROM AUTHOR]

A map of the main landscape units of Congo containing 31 cartographic units was established using vegetation and parent rock types, particle-size distribution and hydromorphy in soils. The average carbon stock in each unit was calculated to a depth of 2 m. The hydromorphy and the particle-size distribution of soils seemed to be the main factors influencing the capacity of soils to store carbon. The average carbon content of Congo soils is 160.5 t/ha for a depth of 0–2 m. The total stock of organic carbon in the mapped area (302,000 km2) is 0.8 Gt at 0–10 cm, 3.3 Gt at 0–100 cm, and 3.9 Gt at 0–200 cm. The stock between 1- and 2-m depth is stable carbon. As its content is relatively constant with depth, the total amount of stable carbon can be roughly estimated at about 1.2 Gt. It could be a sink for carbon dioxide. [Copyright &y& Elsevier]

Background and Objectives Platelet count, thrombopoetin (TPO) level and the compartment of megakaryocyte progenitor cells (CFU-Mk) are major determinants in the regulation of thrombopoiesis. The aim of this study was to investigate the potential changes in the compartment of CFU-Mk and their correlation with serum TPO levels and platelet count after plateletpheresis. Materials and methods Twelve healthy individuals were randomly assigned to undergo single-donor plateletpheresis. A collagen-based in vitro culture system was used to determine the number of peripheral blood (PB) CFU-Mk before and after donation and on days 1, 4 and 7 thereafter. TPO levels were measured by a specific enzyme-linked immunosorbent assay and whole blood counts were performed using an automated cell counter. Results The pre-apheresis platelet count (mean ± SEM: 276 ± 13 × 109/l) decreased after plateletpheresis to a nadir of 194 ± 8 × 109/l (P < 0·001), showed a gradual increase on days 1 and 4, and reached pre-apheresis values by day 7 (280 ± 11). The serum TPO levels were found to be significantly increased on days 1 and 7 as compared to baseline levels (baseline value 103·3 ± 18·5 pg/ml versus day-1 value 135·8 ± 25·8 pg/ml and day-7 value 132 ± 30·19 pg/ml; P < 0·03 and P < 0·03, respectively). The numbers of CFU-Mk in PB were significantly elevated on day 4 only (125 ± 21 colonies/ml of PB versus pre-apheresis values of 68 ± 18 colonies/ml of PB, P < 0·005). Conclusions These findings suggest that platelet loss during plateletpheresis affects thrombopoiesis at the progenitor cell level, probably through alterations in TPO plasma concentrations. [ABSTRACT FROM AUTHOR]

Myelitis is a rare but well documented complication of therapeutic radiation exposure to the spinal cord and is characterized by delayed development of paresthesias, sensory changes and, in severe cases, progressive paresis and paralysis. Although accepted radiation tolerance limits for the spinal cord have successfully limited the incidence of this problem (45–50 Gy, in daily 1.8–2 Gy fractions), aggressive systemic therapy may render patients more susceptible to radiation-related neurotoxicity. We describe the case of a 38-year-old man with refractory non-Hodgkin’s lymphoma who underwent matched sibling peripheral blood stem cell transplant following a conditioning regimen of cyclophosphamide (60 mg/kg × 2) and total body irradiation (120 cGy × 11). This was followed by delivery of 30.6 Gy involved-field radiation at 1.8 Gy/day to the mediastinum and left supraclavicular fossa for bulky residual tumor. Although maximum cumulative radiation dose to the spinal cord was less than 45 Gy, the patient subsequently developed progressive lower extremity weakness and MRI abnormalities of the spinal cord limited to the radiation field. This represents the second report in the literature of this unexpected complication, prompting a need to re-examine current guidelines for radiotherapy in the context of high-dose systemic treatment. Bone Marrow Transplantation (2000) 26, 1355–1359. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of Mycobacterium avium subsp, pamtuberculosis (MAP) in Crohn's disease (CD), using short-term mycobacterial culture media. Methods Sixty-three tissue specimens from 27 CD patients and 36 controls were processed and inoculated into a modified 7H9 broth base medium and incubated at 37°C and 5% CO[sub 2] for up to 1 year Acid-fast staining, determination of mycobactin dependency, PCR analysis using two IS900-derived oligonucleotides and hybridization with an internal probe were performed. Results MAP was present in six of seven (86%) surgically resected tissue samples and in four of 20 (20%) biopsies, with an overall 37% from CD patients, as compared to two of 36 (5.6%) of control specimens. The presence of MAP in Mycobacterial Growth Indicator Tube (MGIT) cultures was detected within 10-12 weeks for surgically resected tissue and after 40 weeks for biopsy specimens, with no MAP growth detected in 12B[sup *] Bactec cultures. Conclusions Because MAP was present in 86% of resected tissue compared to 20% of biopsy specimens from CD patients, we speculate that MAP resides in the submucosal layer closer to the active part of the ulcer rather than on the surface of the mucosal ceils. Thus, surgically resected tissue cultured in MGIT medium is a favorable protocol for rapid cultivation of MAP and for investigating its role in CD pathogenesis. The data support the mycobacterial role in CD pathogenesis. [ABSTRACT FROM AUTHOR]

This study reports an investigation of the behavioral profiles and psychosocial adjustment of subgroups of victims and aggressors in elementary school peer groups. Peer nomination scores for aggression and victimization were used to classify 354 inner-city children (mean age of 10.3 years) into one of four subgroups: aggressive victims, nonaggressive victims, nonvictimized aggressors, and normative contrasts. Subgroup comparisons were then conducted using multi-informant assessment of social behavior, social acceptance-rejection, behavioral regulation, academic functioning, and emotional distress. Children in each of the victim-aggressor subgroups were characterized by a degree of social and behavioral maladjustment. However, impairments in behavioral and emotional regulation were most evident for the aggressive victim subgroup. Aggressive victims were also characterized by academic failure, peer rejection, and emotional distress. The results of this investigation highlight the distinctive nature of the aggressive victim subgroup. [ABSTRACT FROM AUTHOR]

Analyzes the Krebs cycle aconitase gene (acnA) from Streptomyces viridochromogenes. Role of acnA in the isomerization of citrate to isocitrate; Inability of the acnA mutant to develop aerial mycelium; Involvement of acnA in physiological differentiation.

The purpose of this randomized, double-blind study was to test the safety and immunogenicity of an HIV-1LAI recombinant gp160 (rgp160) vaccine in healthy, uninfected volunteers using accelerated dosing schedules. Thirty volunteers were randomly assigned to receive 50-μg doses of rgp 160 in one of two immunization schedules. Group 1 received rgp160 at times 0, 1, 2 and 5 months; and group 2 received rgp160 at times 0, 1, 2, 3 and 4 months. The vaccine was safe and stimulated high levels of HIV-1 envelope-specific binding antibody and T cell memory. There was a trend (P < 0.10) suggesting neutralizing antibodies were better induced by the regimen incorporating a rest period before the final immunization in group 1 volunteers. Both accelerated immunization schedules induced immune responses at levels similar to or better than those achieved by four rgp160 vaccine injections given over 12 - 18 months in other studies. [ABSTRACT FROM AUTHOR]

Presents research which conducted experiments that supported the dislocation- mediated melting scenario for an anisotropic two-dimensional (2D) crystal predicted by Ostlund and Halperin. Distinctive 2D melting transition; Melting of a 2D orthorhombic crystal phase; Smectic phase; Infrared spectroscopy measurements; Longer wavelength height modulation.

The human gut microbiome is a dynamic collection of bacteria, archaea, fungi, and viruses that performs essential functions for immune development, pathogen colonization resistance, and food metabolism. Perturbation of the gut microbiome's ecological balance, commonly by antibiotics, can cause and exacerbate diseases. To predict and successfully rescue such perturbations, first, we must understand the underlying taxonomic and functional dynamics of the microbiome as it changes throughout infancy, childhood, and adulthood. We offer an overview of the healthy gut bacterial architecture over these life stages and comment on vulnerability to short and long courses of antibiotics. Second, the resilience of the microbiome after antibiotic perturbation depends on key characteristics, such as the nature, timing, duration, and spectrum of a course of antibiotics, as well as microbiome modulatory factors such as age, travel, underlying illness, antibiotic resistance pattern, and diet. In this review, we discuss acute and chronic antibiotic perturbations to the microbiome and resistome in the context of microbiome stability and dynamics. We specifically discuss key taxonomic and resistance gene changes that accompany antibiotic treatment of neonates, children, and adults. Restoration of a healthy gut microbial ecosystem after routine antibiotics will require rationally managed exposure to specific antibiotics and microbes. To that end, we review the use of fecal microbiota transplantation and probiotics to direct recolonization of the gut ecosystem. We conclude with our perspectives on how best to assess, predict, and aid recovery of the microbiome after antibiotic perturbation. [ABSTRACT FROM AUTHOR]

We have studied the dynamics of a totally interconnected network of nonlinear amplifiers by building model electronic circuits using dense arrays of resistors and discrete amplifiers. Such models have been discussed recently in the context of spin glasses and neural networks. Even without optimization for speed, these circuits easily reproduce and extend the results of computer simulations in considerably less time. [ABSTRACT FROM AUTHOR]

Polyphase structural mapping and mineral age dating across the Salmon River suture zone in west-central Idaho (Riggins region; ~45°30'N, ~117°W-116°W) support a late Mesozoic history of penetrative deformation, dynamothermal metamorphism, and intermittent magmatism in response to right-oblique oceanic-continental plate convergence (Farallon-North America). High-strain linear-planar tectonite fabrics are recorded along an unbroken ~48 km west-to-east transect extending from the Snake River (Wallowa intra-oceanic arc terrane; eastern Blue Mountains Province) over the northern Seven Devils Mountains into the lower Salmon River Canyon (ancestral North America; western Laurentia). Given the temporally overlapping nature (ca. 145-90 Ma) of east-west contraction in the Sevier fold-and-thrust belt (northern Utah-southeast Idaho-southwest Montana segment), we propose that long-term terrane accretion and marginparallel northward translation in the Cordilleran hinterland (~41°N-46°N latitude; modern coordinates) drove mid- to upper-crustal shortening >250 km eastward into the foreland region (~115°W-113°W). During accretion and translation, the progressive transfer of arc assemblages from subducting (Farallon) to structurally overriding (North American) plates was accommodated by displacement along a shallow westward-dipping basal décollement system underlying the Cordilleran orogen. In this context, large-magnitude horizontal shortening of passive continental margin strata was balanced by the addition of buoyant oceanic crust--late Paleozoic to Mesozoic Blue Mountains Province--to the leading edge of western Laurentia. Consistent with orogenic float modeling (mass conservation, balance, and displacement compatibility), diffuse dextral-transpressional deformation across the accretionary boundary (Salmon River suture: Cordilleran hinterland) was kinematically linked to eastward-propagating structures on the continental interior (Sevier thrust belt; Cordilleran foreland). As an alternative to noncollisional convergent margin orogenesis, we propose a collision-related tectonic origin and contractional evolution for central portions of the Sevier belt. Our timing of terrane accretion supports correlation of the Wallowa terrane with Wrangellia (composite arc/plateau assemblage) and implies diachronous south-to-north suturing and basin closure between Idaho and Alaska. [ABSTRACT FROM AUTHOR]

We present the first X-ray observation at sub-arcsecond resolution of the high-redshift (z  = 6.18) radio-loud quasar CFHQS J142952 + 544717 (J1429). The ∼100 net-count 0.3–7 keV spectrum obtained from ∼30 ks Chandra exposure is best fit by a single power-law model with a photon index Γ = 2.0 ± 0.2 and no indication of an intrinsic absorber, implying a 3.6–72 keV rest-frame luminosity |$L_{\rm X}=(2.3^{+0.6}_{-0.5})\times 10^{46}$|  erg s−1. We identify a second X-ray source at 30″ distance from J1429 position, with a soft (Γ ≃ 2.8) and absorbed (equivalent hydrogen column density N H < 13.4 × 1020 cm−2) spectrum, which likely contaminated J1429 spectra obtained in lower angular resolution observations. Based on the analysis of the Chandra image, the bulk of the X-ray luminosity is produced within the central ∼3 kpc region, either by the disc/corona system, or by a moderately aligned jet. In this context, we discuss the source properties in comparison with samples of low- and high-redshift quasars. We find indication of a possible excess of counts over the expectations for a point-like source in a 0.5″–1.5″ (∼3−8 kpc) annular region. The corresponding X-ray luminosity at J1429 redshift is 4 × 1045 erg s−1. If confirmed, this emission could be related to either a large-scale X-ray jet, or a separate X-ray source. [ABSTRACT FROM AUTHOR]