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Well-conditioned boundary integral methods for the solution of elliptic boundary value problems (BVPs) are powerful tools for static and dynamic physical simulations. When there are many close-to-touching boundaries (e.g., in complex fluids) or when the solution is needed in the bulk, nearly singular integrals must be evaluated at many targets. We show that precomputing a linear map from surface density to an effective source representation renders this task highly efficient, in the common case where each object is “simple”, i.e., its smooth boundary needs only moderately many nodes. We present a kernel-independent method needing only an upsampled smooth surface quadrature, and one dense factorization, for each distinct shape. No (near-)singular quadrature rules are needed. The resulting effective sources are drop-in compatible with fast algorithms, with no local corrections nor bookkeeping. Our extensive numerical tests include 2D FMM-based Helmholtz and Stokes BVPs with up to 1000 objects (281000 unknowns), and a 3D Laplace BVP with 10 ellipsoids separated by 1/30 of a diameter. We include a rigorous analysis for analytic data in 2D and 3D. [ABSTRACT FROM AUTHOR]

Ensembles of particles rotating in a two-dimensional fluid can exhibit chaotic dynamics yet develop signatures of hidden order. Such rotors are found in the natural world spanning vastly disparate length scales — from the rotor proteins in cellular membranes to models of atmospheric dynamics. Here we show that an initially random distribution of either driven rotors in a viscous membrane, or ideal vortices with minute perturbations, spontaneously self assemble into a distinct arrangement. Despite arising from drastically different physics, these systems share a Hamiltonian structure that sets geometrical conservation laws resulting in prominent structural states. We find that the rotationally invariant interactions isotropically suppress long-wavelength fluctuations — a hallmark of a disordered hyperuniform material. With increasing area fraction, the system orders into a hexagonal lattice. In mixtures of two co-rotating populations, the stronger population will gain order from the other and both will become phase enriched. Finally, we show that classical 2D point vortex systems arise as exact limits of the experimentally accessible microscopic membrane rotors, yielding a new system through which to study topological defects. Rotor-like dynamics is observed in many natural systems, from the rotor proteins in cellular membranes to atmospheric models. Here, the authors uncover geometrical conservation laws that limit distribution of driven rotors in a membrane or a soap film and allow to predict their structural states. [ABSTRACT FROM AUTHOR]

Three new bathyal species of Paraliparis (Liparidae) are described from Tinian and Anatahan Islands, and from Esmeralda Bank, in the Mariana Islands. All were collected in shrimp traps set at 903–1207 m. Although liparids have been found, described, and studied at hadal depths in the Mariana Trench, Paraliparis echongpachot sp. nov., Paraliparis kadadakaleguak sp. nov., and Paraliparis marianae sp. nov. are the first species of the family described from bathyal depths of the Mariana Islands. The existence of three species from collections at three locations in the same archipelago, and their distinctiveness from liparids known from other areas in the western Pacific to the north and south of the Mariana Archipelago, is in accordance with the high degree of endemism in species of Paraliparis. Biogeographic and liparid life-history factors that influence bathyal fish distributions in the Mariana Archipelago and enhance endemism in Paraliparis are discussed. [ABSTRACT FROM AUTHOR]

Background: Fecal diversion for chronic, non-healing wounds improves quality of life, assists in wound healing, and helps to prepare for reconstructive surgery. While commonplace, little has been published regarding the safety of diversion in this patient subgroup. The purpose of this study is to elucidate the morbidity and mortality of fecal diversion for chronic wounds and to identify those patients with disproportionately high perioperative risk. Methods: Retrospective analyses were performed using the American College of Surgeons National Surgical Quality Improvement Project (NSQIP) database and an institutional database. The primary outcome analyzed was 30-day mortality and secondary outcomes included 30-day morbidity and readmission rate. Results: Eight hundred fifty-nine patients were identified in the NSQIP database who underwent diversion compared to 3990 who did not. In unmatched data, there were no significant differences in substantial 30-day morbidities. In matched data, diverted patients had a significantly lower perioperative mortality. Fifty-six patients were identified in the institutional review who were diverted for non-healing wounds. Fifty percent of patients with a preoperative ejection fraction of less than 30% died within 30 days of surgery (LR 6.58, p = 0.045). Conclusions: The NSQIP review indicates that fecal diversion does not inherently increase 30-day perioperative morbidity or mortality. While 30-day morbidity remains high, the institutional review suggests that patients with cardiac dysfunction contribute to the majority of complications. As such, an ejection fraction less than 30% may be a relative contraindication to immediate diversion. Medical optimization and elective diversion should be considered whenever feasible. Level of Evidence: Level III, risk / prognostic study. [ABSTRACT FROM AUTHOR]

Christianson syndrome (CS) is an X-linked neurodevelopmental disorder caused by deleterious mutations in SLC9A6. Affected families organized the inaugural Christianson Syndrome Association conference to advance CS knowledge and develop questions that may be prioritized in future research. [ABSTRACT FROM AUTHOR]

Ferroelectrics have recently attracted attention as a candidate class of materials for use in photovoltaic devices, and for the coupling of light absorption with other functional properties. In these materials, the strong inversion symmetry breaking that is due to spontaneous electric polarization promotes the desirable separation of photo-excited carriers and allows voltages higher than the bandgap, which may enable efficiencies beyond the maximum possible in a conventional p-n junction solar cell. Ferroelectric oxides are also stable in a wide range of mechanical, chemical and thermal conditions and can be fabricated using low-cost methods such as sol-gel thin-film deposition and sputtering. Recent work has shown how a decrease in ferroelectric layer thickness and judicious engineering of domain structures and ferroelectric-electrode interfaces can greatly increase the current harvested from ferroelectric absorber materials, increasing the power conversion efficiency from about 10−4 to about 0.5 per cent. Further improvements in photovoltaic efficiency have been inhibited by the wide bandgaps (2.7-4 electronvolts) of ferroelectric oxides, which allow the use of only 8-20 per cent of the solar spectrum. Here we describe a family of single-phase solid oxide solutions made from low-cost and non-toxic elements using conventional solid-state methods: [KNbO3]1 − x[BaNi1/2Nb1/2O3 − δ]x (KBNNO). These oxides exhibit both ferroelectricity and a wide variation of direct bandgaps in the range 1.1-3.8 electronvolts. In particular, the x = 0.1 composition is polar at room temperature, has a direct bandgap of 1.39 electronvolts and has a photocurrent density approximately 50 times larger than that of the classic ferroelectric (Pb,La)(Zr,Ti)O3 material. The ability of KBNNO to absorb three to six times more solar energy than the current ferroelectric materials suggests a route to viable ferroelectric semiconductor-based cells for solar energy conversion and other applications. [ABSTRACT FROM AUTHOR]

A primary objective of the ICEFISH 2004 cruise was to collect and study notothenioid fishes from remote localities in the Atlantic sector of the Southern Ocean. Nearly 1 month was devoted to bottom trawling for fishes on the shelf and upper slope (to 1,000 m) areas around Shag Rocks, South Georgia, South Sandwich Islands and Bouvetøya. The focus was on the latter two locations, because their faunas are more poorly known. Eight species were collected at Shag Rocks with Patagonotothen guntheri most abundant; 17 at South Georgia with Lepidonotothen nudifrons, L. larseni and Gobionotothen gibberifrons most abundant; 13 at the South Sandwich Islands with L. larseni, L. nudifrons and G. gibberifrons most abundant; and 11 at Bouvetøya with L. larseni, Macrourus holotrachys and L. squamifrons most abundant. Ten new locality records were established: Shag Rocks (1), South Georgia (1), South Sandwich Islands (5), South Sandwich Trench at 5,350 m (1) and Bouvetøya (2). Total known demersal fish diversity on the shelf and upper slope at Shag Rocks/South Georgia, South Sandwich Islands and Bouvetøya is 42, 31 and 17 species, respectively. To examine population structure in the four most abundant notothenioids at Bouvetøya ( L. larseni, L. squamifrons, Notothenia coriiceps and Chaenocephalus aceratus), we examined the ND2 portion of mitochondrial DNA. Chaenocephalus aceratus, N. coriiceps and L. larseni exhibited no significant genetic differentiation in comparison with samples from localities in the Scotia Sea and the Antarctic Peninsula. However, L. squamifrons showed significant genetic differentiation between the South Shetlands and Bouvetøya populations ( F ST = 0.189, P = 0.015). Thus, these data combined with previous studies of two other notothenioids suggest that five of the six notothenioid species at Bouvetøya are not genetically differentiated from other localities in the Atlantic sector of the Southern Ocean. The location of Bouvetøya within the Antarctic Circumpolar Current and the long (1–2 years) pelagic stages of the notothenioids at Bouvetøya may be at least partly responsible for this genetic homogeneity. [ABSTRACT FROM AUTHOR]

New methods to combat influenza A virus (FLUAV) in humans and animals are needed. The H3N8 subtype virus was the cause of the pandemic of 1890 and has recently undergone cross-species transmission from horses to dogs in the USA. In 2007 H3N8 spread to Australia, a continent previously devoid of equine influenza. Here, we show that antisense-peptide-conjugated phosphorodiamidate morpholino oligomers (PPMOs), delivered by intranasal administration, are able to inhibit the replication of FLUAV A/Eq/Miami/1/63 (H3N8) in mice by over 95% compared to controls. Monitoring of body weight and immune cell infiltrates in the lungs of noninfected mice indicated that PPMO treatment was not toxic at a concentration shown to be effectively antiviral in vivo. In addition, we detected a naturally occurring mutation within the PPMO target site of a viral gene that may be the cause of resistance to one of the two antisense PPMO sequences tested. These data indicate that PPMOs targeting highly conserved regions of FLUAV are promising novel therapeutic candidates. [ABSTRACT FROM AUTHOR]

During the ICEFISH cruise of 2004 13 specimens of the fish family Liparidae (Scorpaeniformes) were collected from Burdwood Bank and near South Georgia. These specimens, with the addition of three more from the King Edward Point Laboratory of the British Antarctic Survey, represent nine species. Two of these are new and are described herein: Careproctus stigmatogenus new species and C. maculosus new species; the second specimen of C. minimus Andriashev and Stein is reported and described, specimens of C. georgianus Lönnberg, C. falklandicus (Lönnberg), C. ?pallidus (Vaillant), Paraliparis copei gibbericeps Andriashev, P. gracilis Norman, and P. tetrapteryx Andriashev and Neelov are reported, and live color of C. georgianus, C. falklandicus, and P. tetrapteryx is described and shown. [ABSTRACT FROM AUTHOR]

Abyssal and midslope Arctic benthic fishes were sampled nonquantitatively by still photography and videography from a remotely operated vehicle (ROV) between 13 August and 7 September 2002. Species diversity was low: only six putative species were seen, includingLycodes frigidusCollett 1879,Lycodessp.,Rhodichthys reginaCollett 1879,Paraliparis bathybius(Collett 1879),Raja (Amblyraja) hyperboreaCollett 1879, andCottunculusspecies diversity varied among stations sampled. An analysis of 1-min segments of videotape from one long ROV dive suggested that habitat selection by demersal nekton in these environments may be associated with the presence, absence, or density of other benthic animals. [ABSTRACT FROM AUTHOR]

Androgen deprivation therapy causes a paradoxical elevation of matrix metalloproteinases (MMPs) including MMP-9 resulting in aggressive tumor phenotype in many patients with prostate cancer. In this study, we have evaluated a novel antisense phosphorodiamidate Morpholino oligomer (PMO) targeted against MMP-9 in models of angiogenesis and in human prostate xenograft in athymic mice. The treatment of androgen-independent DU145 human prostate cells with a 21-mer MMP-9 antisense PMO caused a dose-dependent inhibition of cell proliferation compared to scrambled or MMP-2 antisense PMO at similar concentrations. This was associated with decreases in MMP-9 expression, gelatinolytic activity and increased stability of the insulin-like growth factor-binding protein (IGFBP-3), a proapoptotic factor and MMP-9 substrate. In vitro invasion assays revealed a 40-60% inhibition of DU145 cell invasion in the presence of 25?µM MMP-9 antisense PMO. A significant decrease in endothelial cell migration and vascularization was observed in the Matrigel plug assay in mice when treated intraperitoneally with 300?µg/day MMP-9 antisense for 21 days. In the highly vascular DU145 tumor xenografts, MMP-9 inhibition caused decreased tumor growth with regression in 50% of the animals. Histological analysis revealed increased apoptosis and fibrous tissue deposits in the MMP-9 antisense-treated tumors compared to the scrambled and saline controls. No apparent toxicity or mortality was associated with the MMP-9 PMO treatment. In summary, the MMP-9 antisense PMO inhibited in vitro prostate cancer cell proliferation, invasion and in vivo angiogenesis. These data establish the feasibility of developing a site-directed, nontoxic antisense therapeutic agent for inhibiting local invasion and metastasis.Cancer Gene Therapy (2003) 10, 823-832. doi:10.1038/sj.cgt.7700642 [ABSTRACT FROM AUTHOR]

Measurement of serum AFP can be useful in the diagnosis of hepatocellular carcinoma (HCC). AFP is a fetal protein that is not normally present in the serum of adults but is elevated in most patients with HCC. The diagnosis of HCC is generally made in patients with a mass lesion in a cirrhotic liver if the AFP is over 400 ng/ml. Unfortunately, AFP is elevated in other conditions such as nonseminomatous germ cell tumor, chronic hepatitis, cirrhosis, pregnancy, and hepatic metastasis. A high AFP cutoff value for HCC would increase the specificity of the test, but would decrease the sensitivity considerably. We report the case of a patient with HCV and cirrhosis with a markedly elevated AFP of 1257 ng/ml in whom no evidence of HCC could be found after a thorough radiologic and histologic evaluation. Despite a virologic nonresponse to IFN-alpha2b and ribavirin therapy, there was a complete normalization of AFP. [ABSTRACT FROM AUTHOR]

Presents a case of a patient with chronic hepatitis c virus and cirrhosis with an alpha-fetoprotein. Case history; Radiologic and histologic findings; Treatment.

Recent studies in vertebrates and Drosophila melanogaster have revealed that Fringe-mediated activation of the Notch pathway has a role in patterning cell layers during organogenesis. In these processes, a homeobox-containing transcription factor is responsible for spatially regulating fringe (fng) expression and thus directing activation of the Notch pathway along the fng expression border. Here we show that this may be a general mechanism for patterning epithelial cell layers. At three stages in Drosophila oogenesis, mirror (mirr) and fng have complementary expression patterns in the follicle-cell epithelial layer, and at all three stages loss of mirr enlarges, and ectopic expression of mirr restricts, fng expression, with consequences for follicle-cell patterning. These morphological changes are similar to those caused by Notch mutations. Ectopic expression of mirr in the posterior follicle cells induces a stripe of rhomboid (rho) expression and represses pipe (pip), a gene with a role in the establishment of the dorsal-ventral axis, at a distance. Ectopic Notch activation has a similar long-range effect on pip. Our results suggest that Mirror and Notch induce secretion of diffusible morphogens and we have identified TGF-β (encoded by dpp) as such a molecule in germarium. We also found that mirr expression in dorsal follicle cells is induced by the EGF-receptor (EGFR) pathway and that mirr then represses pip expression in all but the ventral follicle cells, connecting EGFR activation in the dorsal follicle cells to repression of pip in the dorsal and lateral follicle cells. Our results suggest that the differentiation of ventral follicle cells is not a direct consequence of germline signalling, but depends on long-range signals from dorsal follicle cells, and provide a link between early and late events in Drosophila embryonic dorsal-ventral axis formation. [ABSTRACT FROM AUTHOR]

This study was designed to determine whether swallow rehabilitation outcomes were affected by the type of evaluation procedure utilized by the clinician. The two evaluation techniques compared were the bedside examination and videofluoroscopy (the modified barium swallow). Ten institutions participated in this study, enrolling a total of 103 partial laryngectomized patients, 21 in the bedside arm and 82 in the videofluoroscopy arm. Data on recovery of oral intake were collected weekly. All patients received an X-ray study of swallow at 3 months after the operation. Mean time to oral intake of food was significantly lower in patients assessed with bedside examination. Overall swallow measures of transit times and swallow efficiencies after 3 months revealed significantly better function in the videofluoroscopy group. Results are discussed in terms of the visibility of swallow physiology with the two assessment techniques, the accuracy of therapy planning with the bedside examination versus videofluoroscopy and the ability of head and neck cancer patients to tolerate some aspiration without developing aspiration pneumonia. [ABSTRACT FROM AUTHOR]

Bowel necrosis is an uncommon complication of pancreatitis. Two patients are reported who developed ileocecal and descending colon changes as a result of ischemia following severe pancreatitis. Arteriography in one patient confirmed the presence of intraluminal thrombi. [ABSTRACT FROM AUTHOR]

Optical interferometry was used to quantitatively characterize the surface of chemical-mechanical polishing (CMP) pads used to polish oxide films. We discuss the optical interferometry technique, including a description of the parameters necessary to compare pad samples. Flat, mesa-like structures formed on the pad during the first 5 min polish when conditioning was not used. The data from the optical interferometer indicated that the surface topography did not change with subsequent polishing, even though the thermal oxide removal rate continued to decrease. We found conditioning roughened the pad surface. Rougher pad surfaces removed more oxide during a single 5 min polish than comparatively smooth pad surfaces. Data indicates that conditioning increases and stabilizes pad surface roughness. [ABSTRACT FROM AUTHOR]

Descriptive information on the deep-sea Southern Ocean ophidioid Holcomycteronus brucei is limited to the holotype, and the species of the genus Holcomycteronus are poorly known. During the international ICEFISH cruise of 2004 a specimen was collected west of South Georgia in 2,705–2,721 m. A third, unreported specimen collected south of Tasmania in 2,840–3,001 m was located after the cruise. These specimens are described and compared to other nominal species of Holcomycteronus pending a generic review. [ABSTRACT FROM AUTHOR]

An abstract of the article "Mycobacterium Avium Intracellulare Complex (MAC) Presenting With Marked Jaundice and Duodenal Ulcerations," by David F. Stein, Reza Sianati, Kodlipet Dharmashankar, Mihai Smina, Richard Hwang, and Judith Berger is presented.

An abstract of the article "Inappropriate Use of Stress Ulcer Prophylaxis: A Community Teaching Hospital's Experience," by David F. Stein, Mezgebe Berhe, Joel Penalo, Jose Reinoso, Edwin Pena, Rafael Nunez, Oscar Oropeza, and Manuel Perez is presented.