Minimal Residue Research Articles

Efficient and accurate simulation of dynamic dielectric objects

Electrostatic interactions between dielectric objects are complex and of a many-body nature, owing to induced surface bound charge. We present a collection of techniques to simulate dynamical dielectric objects. We calculate the surface bound charge from a matrix equation using the Generalized Minimal Residue method (GMRES). Empirically, we find that GMRES converges very quickly. Indeed, our detailed analysis suggests that the relevant matrix has a very compact spectrum for all non-degenerate dielectric geometries. Each GMRES iteration can be evaluated using a fast Ewald solver with cost that scales linearly or near-linearly in the number of surface charge elements. We analyze several previously proposed methods for calculating the bound charge, and show that our approach compares favorably.

A Practical Strategy of Monitoring Minimal Residue Disease and Intervention for Central Nervous System Relapse of Childhood Acute Lymphoblastic Leukemia

To investigate monitoring minimal residual disease (MRD) using cerebral spinal fluid for predicting central nervous system leukemia (CNSL) and treatment. There is no survival difference between enhanced triple intrathecal therapy (ETIT) and cranial radiation for CNSL patients with positive morphology and MRD. Positive MRD correlated with CNSL, whereas negative MRD indicated a lower chance of CNSL recurrence. Altogether 79 cerebral spinal fluid specimens indicating negative morphology but positive MRD were given either ETIT or conventional triple intrathecal therapy. The ETIT group indicated lower relapse. Flow cytometry is sensitive to predict CNSL and ETIT is a potent intervention.

Combined effects of high pressure and sodium hydrogen carbonate treatment on pork ham: improvement of texture and palatability

In this study, the combined effects of high pressure and sodium hydrogen carbonate (NaHCO3) treatment on the physical and chemical properties, and palatability of pork ham, a tough and under-utilized meat, were investigated. Assessment of meat properties with heat treatment, after exposure to NaHCO3 and high pressure treatment, revealed an increase in water content, and decreased weight reduction and rupture stress. The free amino acid content of meat samples increased with NaHCO3 and high pressure treatment. The effect of high pressure processing was especially notable at a pressure of 300 MPa. Sensory evaluation showed that meat subjected to high pressure processing after NaHCO3 treatment was tender and juicy. In addition, the sample produced minimal residue in the mouth and was characterized by a good taste.

Targeting BCR-ABL Oncoprotein for Leukemia Therapy: Current Biotechnology and Future Perspectives

The chimeric oncoprotein BCR-ABL, resulting from Philadelphia (Ph) chromosome translocation, is crucial for the pathogenesis of chronic myelogenous leukemia (CML) as well as a subset of acute lymphoblastic leukemia (ALL). Due to the loss of regulatory motifs during the fusion process, BCR-ABL has constitutive tyrosine kinase activity that is critical for oncogenesis. This provides the rationale for developing drugs that specifically inhibit BCR-ABL tyrosine kinase activity. The first tyrosine kinase inhibitor (TKI), imatinib mesylate (STI571, Gleevec®), was launched in 2001, completely changing the landscape of therapy for CML. However, imatinib-resistant cases emerged in the clinic, most caused by mutations in the BCR-ABL tyrosine kinase domain or BCR-ABL gene amplification. This urged the development of next-generation TKIs that can override imatinib-resistance. Instead of inhibiting tyrosine kinase activity, an alternative strategy, currently being tested in clinical trials, is to induce BCR-ABL degradation by heat shock protein 90 inhibitors or proteasome inhibitors. A more tentative strategy is to entrap BCR-ABL in the nucleus based on the finding that nuclear BCR-ABL is pro-apoptotic. Moreover, the unique mRNA and amino acid sequences at the junctional region of BCR-ABL provide an opportunity for specific targeting by gene therapy and immunotherapy, respectively. Therefore, a deep understanding of the biology of BCR-ABL in the context of CML and the use of state-of-the-art biotechnology have aided and will continue to aid in the development of targeted therapy for BCR-ABL-driven leukemia and minimal residue disease (MRD). Keywords: Antisense therapy, ALL, BCR-ABL, CML, HSP90 inhibitor, imatinib, imatinib-resistance, leukemia vaccine, minimal residual disease, nuclear entrapment, proteasome inhibitor, ribozyme, RNA interference, T315I mutation, tyrosine kinase inhibitor.

Deep anisotropic LiNbO3 etching with SF6/Ar inductively coupled plasmas

A SF6/Ar inductively coupled plasma (ICP) technique was investigated to improve etching of proton exchanged LiNbO3. The influences of He backside cooling, power, and gas flows on characteristics such as etching rate, sidewall slope angle, and surface roughness were investigated. Total gas flow is a key parameter that affects etching results, and an optimized gas flow (50 sccm) was used for lengthy etching processes (30 min). Deep (>3 μm) and highly anisotropic etching, as well as ultra smooth LiNbO3 surfaces were achieved in a single-step run. The authors’ proposed method has achieved the deepest, most vertical, minimal residue structure yet reported for single-step ICP etching.

Manure Composition and Incorporation Effects on Phosphorus in Runoff Following Corn Biomass Removal

Greater demand for corn ( L.) stover for bioenergy use may lead to increased corn production acreage with minimal surface residue cover, resulting in greater risk for soil erosion and phosphorus (P) losses in runoff. A rainfall simulation study was conducted to determine the effects of spring-applied dairy cow () manure (none, in-barn composted, and exterior walled-enclosure pit) with >200 g kg organic solids content following fall corn biomass removal with and without incorporation (chisel plow [CP] and no-till [NT]) on sediment and P in runoff. Runoff was collected from a 0.83-m area for 60 min following the onset of rainfall simulation (76 mm h), once in spring and once in fall. Runoff dissolved reactive P (DRP) and dissolved organic P (DOP) concentrations were positively correlated with manure P rate and were higher in NT compared with CP. Conversely, sediment and particulate P (PP) concentrations in runoff were inversely correlated with manure P rate (and manure solids) and were higher in CP compared with NT. Runoff volume where no manure was applied was higher in NT than in CP in spring but similar in fall. The addition of manure reduced runoff volumes by an average of 82% in NT and 42% in CP over spring and fall. Results from this study indicate that surface application of dairy manure with relatively high solids content may reduce sediment and PP losses in runoff without increasing the risk of increased DRP and DOP losses in the year of application where corn biomass is harvested.

Sequence-independent Control of Peptide Conformation in Liposomal Vaccines for Targeting Protein Misfolding Diseases

Synthetic peptide immunogens that mimic the conformation of a target epitope of pathological relevance offer the possibility to precisely control the immune response specificity. Here, we performed conformational analyses using a panel of peptides in order to investigate the key parameters controlling their conformation upon integration into liposomal bilayers. These revealed that the peptide lipidation pattern, the lipid anchor chain length, and the liposome surface charge all significantly alter peptide conformation. Peptide aggregation could also be modulated post-liposome assembly by the addition of distinct small molecule β-sheet breakers. Immunization of both mice and monkeys with a model liposomal vaccine containing β-sheet aggregated lipopeptide (Palm1-15) induced polyclonal IgG antibodies that specifically recognized β-sheet multimers over monomer or non-pathological native protein. The rational design of liposome-bound peptide immunogens with defined conformation opens up the possibility to generate vaccines against a range of protein misfolding diseases, such as Alzheimer disease.

Between Ethics and Aesthetics: The Residual in Samuel Beckett's Minimalism

This article offers a comparative analysis of 1960s minimalism in visual art (Robert Morris and Richard Tuttle) and music (Philip Glass and Steve Reich) on the one hand, and Samuel Beckett’s prose texts Tetes-mortes (1967) and ‘Sans’ (1969) on the other, allowing for a rethinking of Beckett’s later aesthetics. Taking into account a lesser-known study of Beckett by Adorno and tying this in with the more famous theories of Maurice Blanchot, Alain Badiou and Jacques Derrida, the ethical dimension of minimalism is brought to the fore in order to shed new light on an art movement which has often been deemed to be a dead-end in art history. In particular, the article seeks to explore Beckett’s ethics of the minimal residue as a response to the catastrophe of the Holocaust, and as a consequent form of resistance to incorporation, appropriation and annihilation.

Successful treatment of delayed aortobifemoral graft thrombosis with manual aspiration thrombectomy

We present a 67-year-old man who had undergone aortobifemoral synthetic graft surgery one year earlier. The patient experienced thrombosis of the graft nine months after the operation, and thrombectomy of the graft was planned. However, the patient refused to undergo repeat surgery for thrombus removal and was referred to our center for possible endovascular treatment. We treated the patient with percutaneous aspiration thrombectomy. The thrombi were chronic in nature but could be removed with minimal residue in any part of the graft by using repeated aspiration thrombectomy with 7 F guiding catheters. Underlying stenosis of both distal graft anastomoses was treated with percutaneous balloon angioplasty, and a self-expanding stent was deployed on the right distal anastomosis. A small fragment of thrombus embolized to the right popliteal artery and was removed with aspiration thrombectomy through a second antegrade puncture on the right side. We believe this is the first report of aspiration thrombectomy for an aortobifemoral graft thrombosis. The method was successful despite the chronic nature of the thrombi. Manual aspiration thrombectomy with largebore guiding catheters can be used as an effective recanalization method for delayed aortobifemoral graft occlusion and could be regarded as a good alternative technique to surgical thrombectomy in selected patients.

Peering into the aftermath: The inhospitable host?

Much of how the human host responds to a tumor and to anticancer therapy is still not fully fleshed out. The cytokines and other mediators involved in this response may be both allies and enemies in the quest for more effective treatments or even a cancer cure. In 'Bedside to Bench', Robert Kerbel and John Ebos discuss recent human studies in healthy individuals and people with minimal residue or no disease showing release of host-derived cytokines after antiangiogenic therapy. The increase in proangiogenic factors such as VEGF and PIGF and other cytokines involved in metastasis and tumor repopulation in a host may threaten therapeutic success but may also suggest new prognostic markers and other treatment strategies. In 'Bench to Bedside', Michael Karin and Florian Greten peruse how using JAK2 inhibitors to block STAT3 in tumors could halt cancer progression. JAK2 inhibitors, already being tested in clinical trials to treat myeloproliferative diseases, may also prove valid as anticancer drugs.

THE SIGNIFICANCE OF DETECTING WT1 EXPRESSION IN CHILDHOOD ACUTE LEUKEMIAS

WT1 (Wilms' tumor gene 1) overexpression is implicated in the prognosis of acute leukemia. The purpose of this study was to investigate WT1 expression and its clinical implication in childhood acute leukemia (AL) in Chinese population. Bone marrow specimen from 200 children at different stages of acute leukemia and from 21 children without leukemia were studied. The WT1 expression at diagnostic marrow specimen in both acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL) was higher than control group, whereas WT1 expression in AML was higher than in ALL, and WT1 expression level in relapse in ALL increased more significantly than in AML. The WT1 expression level showed positive correlation with the hypodiploidy and BCR-ABL fusion gene in acute leukemia. A rapidly decrease of WT1 expression level predicted a good response to the induction therapy and low expression of WT1 correlates with remission status. This study suggested that WT1 expression levels in acute leukemia can potentially be a marker for evaluating therapeutic efficacy, correlating with monitoring minimal residue disease, and predicting hematological relapse in children acute leukemia.

Comparative impact of a single application of selected broad spectrum herbicides on ecological components of oil palm plantation

Proper choice and use of herbicides are important for the effective control of weed and environmental safety. Herbicides which possess both characteristics are preferred for use in weed control operation. A study was, therefore, conducted to compare the performance of common broad-spectrum herbicides of paraquat, glyphosate and glufosinate-ammonium to control weeds and their impact to the surrounding ecological components of an oil palm plantation. Field experiments set up in the oil palm plantation were sprayed accordingly with recommended rates of the herbicides (paraquat, 600 g a.i. ha-1; glufosinate-ammonium, 600 g a.i. ha-1 and glyphosate, 1200 g a.i. ha-1) at 200 L ha-1, using knapsack sprayer fitted with a 2.5 deflector nozzle. Untreated control plots were included in the experiment. The effectiveness of the herbicides on weed population, their residues in the soil and indirect effects on oil palm crop plants were evaluated. Paraquat killed 74% of the weed population with effective control period of 8.8 WAT, whereas, both glyphosate and glufosinate-ammonium caused maximum killed of 99% and remained effective until 14.8 WAT. The measurements of weed dry weight and growth reduction also indicated that the herbicides caused significant reduction compared with the control, but paraquat was comparatively less effective than glyphosate and glufosinate-ammonium. Minimal and insignificant residue levels of the herbicides were detected in the soil after application which caused no significant detrimental effect on oil palm crop development and production, or the microorganism populations (fungi and bacteria) in the soil. The study indicated that the use of the herbicides can be effective in controlling the mixed weed population in oil palm plantation; glyphosate and glufosinate-ammonium showed greater effectiveness than paraquat. The herbicides, applied at their recommended rates, left no residual effects on the surrounding ecological components of oil palm plantation. Key words: Herbicide efficacy, mixed weeds, young oil palm, paraquat, glufosinate-ammonium, glyphosate.

Highly Volatile Alkaline Earth Metal Fluoroalkoxides

The synthetic strategies, structural comparison, and thermal gravimetric analyses for a novel family of alkaline earth metal perfluoro-tert-butoxides (PFTB) are presented. The isolated complexes follow the general formula, [Ae(PFTB)(2)(d)(x)]; (1a, Ae = Mg, d = THF, x = 2; 1b, Ae = Ca, d = THF, x = 4; 1c, Ae = Sr, d = THF, x = 4; 1d, Ae = Ba, d = THF, x = 4; 2a, Ae = Mg, d = DME, x = 1; 2b, Ae = Ca, d = DME, x = 2; 2c, Ae = Sr, d = DME, x = 2; 2d, Ae = Ba, d = DME, x = 3; 3a, Ae = Mg, d = diglyme, x = 1; 3b, Ae = Ca, d = diglyme, x = 2; 3c, Ae = Sr, d = diglyme, x = 2; 3d, Ae = Ba, d = diglyme, x = 2; THF = tetrahydrofuran, DME = 1,2-dimethoxyethane) where the crystallographically characterized compounds display either a cis or trans conformations in octahedral or pseudo-octahedral environments. Alkane elimination (Mg), direct metalation via ammonia activation (Ca, Sr, Ba), and transamination (Ca, Sr, Ba) methods yielded the target compounds in moderate to good yields. Structural studies of select compounds showed all compounds to be monomeric with varying degrees of co-ligand coordination, possibly explaining some of the observed physical properties. Thermal gravimetric analyses of the compounds shows sublimation at low temperatures, associated with minimal residue, making this family of fluoroalkoxides promising candidates for metal organic chemical vapor deposition (MOCVD).

Estimation of surface soil organic matter using a ground-based active sensor and aerial imagery

Active canopy sensors are currently being studied as a tool to assess crop N status and direct in-season N applications. The objective of this study was to use a variety of strategies to evaluate the capability of an active sensor and a wide-band aerial image to estimate surface soil organic matter (OM). Grid soil samples, active sensor reflectance and bare soil aerial images were obtained from six fields in central Nebraska before the 2007 and 2008 growing seasons. Six different strategies to predict OM were developed and tested by dividing samples randomly into calibration and validation datasets. Strategies included uniform, interpolation, universal, field-specific, intercept-adjusted and multiple-layer prediction models. By adjusting regression intercept values for each field, OM was predicted using a single sensor or image data layer. Across all fields, the uniform and universal prediction models resulted in less accurate predictions of OM than any of the other methods tested. The most accurate predictions of OM were obtained using interpolation, field-specific and intercept-adjusted strategies. Increased accuracy in mapping soil OM using an active sensor or aerial image may be achieved by acquiring the data when there is minimal surface residue or where it has been excluded from the sensor’s field-of-view. Alternatively, accuracy could be increased by accounting for soil moisture content with supplementary sensors at the time of data collection, by focusing on the relationship between soil reflectance and soil OM content in the 0–1 cm soil depth or through the use of a subsurface active optical sensor.

In vivo quantitation of metabolites with an incomplete model function

Metabolites can serve as biomarkers. Estimation of metabolite concentrations from an in vivo magnetic resonance spectroscopy (MRS) signal often uses a reference signal to estimate a model function of the spectral lineshape. When no reference signal is available, the a priori unknown in vivo lineshape must be inferred from the data at hand. This makes quantitation of metabolites from in vivo MRS signals a semi-parametric estimation problem which, in turn, implies setting of hyper-parameters by users of the software involved. Estimation of metabolite concentrations is usually done by nonlinear least-squares (NLLS) fitting of a physical model function based on minimizing the residue. In this work, the semi-parametric task is handled by complementing the usual criterion of minimal residue with a second criterion acting in tandem with it. This second criterion is derived from the general physical knowledge that the width of the line is limited. The limit on the width is a hyper-parameter; its setting appeared not critical so far. The only other hyper-parameter is the relative weight of the two criteria. But its setting too is not critical. Attendant estimation errors, obtained from a Monte Carlo calculation, show that the two-criterion NLLS approach successfully handles the semi-parametric aspect of metabolite quantitation.

High WT1 gene expression before haematopoietic stem cell transplant in children with acute myeloid leukaemia predicts poor event‐free survival

WT1 gene expression has been proposed as a useful marker of minimal residual disease in leukaemia. Its utility in paediatric haematopoietic stem cell transplantation (HSCT) has not been studied. We studied the prognostic value of WT1 expression in peripheral blood prior to HSCT in 36 children with acute myeloid leukaemia (AML). Samples were obtained 2 weeks pre-transplant to determine the level of WT1 expression. WT1 expression was normalized using K562 cells as a control and a relative value of 0.5 was chosen as the cut-off point between high and low WT1 expression. The median level of pre-transplant WT1 expression in the 36 patients was 0.09 (range 0.0001-11.0), with 11 patients having WT1 >or= 0.5 and 25, WT1 < 0.5. After HSCT, 76% of patients with high pre-transplant WT1 expression relapsed, in contrast to 0% of the patients with low WT1 expression. Those with high WT1 expression had significantly lower 5-year event-free survival (EFS) (18%, 95% CI 0-40%) as compared to those with low WT1 expression (68%, 95% CI 50-86%, P = 0.007). Multivariate analysis showed that pre-transplant WT1 level is the only significant prognostic factor for the difference in EFS. Our finding suggests that elevated WT1 gene expression before HSCT in paediatric AML predicts relapse and poor long-term EFS. A larger prospective study is warranted to compare the value of high WT1 expression and other markers of minimal residue disease in predicting clinical outcomes after HSCT.

Observations of the field-aligned residual flow inside magnetic cloud structure

In this paper, we report two MC events observed by WIND spacecraft with good examples of field-aligned residual flow inside the MC structure. For both events, the co-moving frames are determined through the deHoffman-Teller (HT) analysis and the axial orientations are inferred by the newly developed minimal residue (MR) method. The nature coordinate system for both events are constructed with velocity of the HT frame and the inferred MC axis, the field and flow remaining in the HT frame are analyzed at this coordinate system. As a result, we find that the residual flows in the co-moving HT frame of the two MC events are almost anti-parallel to the helical magnetic field. We speculate that the field-aligned residual flows are large scale coherent hydrodynamic vortices co-moving with the MCs at the supersonic speed near 1 AU. Data analyses show that the event in slow ambient solar wind is expanding at 1 AU and another one in fast solar wind does not show apparent expansion. Proton behaviors for both events are quasi-isothermal. Accelerated HT analysis shows that both events have no suitable HT frame with constant accelerations, which suggests that both events may be moving at the constant speed near 1 AU under the assumptions of the HT analysis. For both events, the ratio of the dynamic pressure to the magnetic pressure is larger than that of the thermal pressure to magnetic pressure, which suggests that the dynamic effects due to the plasma flows remaining in the co-moving HT frame are more important than the thermal effects in the study of MC evolution and propagation.

Ageing and thermal degradation of plasma polymerised thin films derived from Lavandula angustifolia essential oil

The ageing and thermal degradation of polymer thin films derived from the essential oil of Lavandula angustifolia (LA) fabricated using plasma polymerisation were investigated. Spectroscopic ellipsometry and Fourier transform infrared (FTIR) spectroscopy were employed to monitor the optical parameters, thickness and chemical structure of the polyLA films fabricated at various RF powers over a period of 1400 h. The bulk of the degradation under ambient conditions was found to occur within the first 100 h after fabrication. The thermal degradation of the polyLA films was also investigated using the ellipsometry and FTIR. An increase in thermal stability was found for films fabricated at increased RF power levels. Between 200 and 300 °C, the properties indicate that a phase change occurs in the material. Samples annealed up to 405 °C demonstrated minimal residue, with retention ranging between 0.47 and 2.2%. A tuneable degradation onset temperature and minimal residue post-anneal demonstrate that the polyLA films are excellent candidates for sacrificial material in air gap fabrication.

Ex vivo expansion of CD34+ and T and NK cells from umbilical cord blood for leukemic BALB/C nude mouse transplantation

CBSCT with low incidence of GVHD is associated with higher rates of delayed engraftment and relapse compared with other stem cells transplants. The immune-mediated effect of NK and cytotoxic T cells against residual tumor cells was shown to prevent relapse and reinduce remission after bone marrow transplantation. We expanded CD34+ and T and NK cells ex vivo in cord blood with different cytokines combination and transplanted into leukemic BALB/C nude mouse. The results showed significant expansion of MNCs and CD34+ cells. The CD3+ T cells increased in the groups containing cytokines cocktail, especially in the group with IL-7 or IL-2. CD56+ NK cells number increased significantly only in a medium containing IL-2. Of the 20 engrafted BALB/C nude mice, 14 survived after 6 weeks transplantation, and the numbers in each group were from 3 to 4. Human CD3+ cells in the bone marrow of the survived mice were analyzed by flow cytometry and showed existing evidences. RT-PCR was used to detect leukemic fusion bcr/abl gene; all mice that experienced expanded cord blood transplantation could not be found to have expression of fusion bcr/abl gene. These suggest that T, NK cells as well as CD34+ cells could be expanded from CB MNCs in the same medium with the combination of cytokines. The expanded CB MNCs could reconstitute hematopoiesis and eliminate minimal residue leukemia disease in transplanted mice.

A multilevel graph algorithm for two dimensional phase unwrapping

Two-dimensional phase unwrapping is the problem of deducing unambiguous “phase” from values known only modulo 2π. Many authors agree that the objective of phase unwrapping should be to find a weighted minimum of the number of places where adjacent (discrete) phase values differ by more than π (called discontinuities). This NP-hard problem is of considerable practical interest, largely due to its importance in interpreting data acquired with synthetic aperture radar (SAR) interferometry. Consequently, many heuristic algorithms have been proposed. We present an efficient multi-level graph algorithm for the approximate solution of an equivalent problem—minimal residue cut in the dual graph.