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Undesired coupling to the surrounding environment destroys long-range correlations in quantum processors and hinders coherent evolution in the nominally available computational space. This noise is an outstanding challenge when leveraging the computation power of near-term quantum processors1. It has been shown that benchmarking random circuit sampling with cross-entropy benchmarking can provide an estimate of the effective size of the Hilbert space coherently available2–8. Nevertheless, quantum algorithms’ outputs can be trivialized by noise, making them susceptible to classical computation spoofing. Here, by implementing an algorithm for random circuit sampling, we demonstrate experimentally that two phase transitions are observable with cross-entropy benchmarking, which we explain theoretically with a statistical model. The first is a dynamical transition as a function of the number of cycles and is the continuation of the anti-concentration point in the noiseless case. The second is a quantum phase transition controlled by the error per cycle; to identify it analytically and experimentally, we create a weak-link model, which allows us to vary the strength of the noise versus coherent evolution. Furthermore, by presenting a random circuit sampling experiment in the weak-noise phase with 67 qubits at 32 cycles, we demonstrate that the computational cost of our experiment is beyond the capabilities of existing classical supercomputers. Our experimental and theoretical work establishes the existence of transitions to a stable, computationally complex phase that is reachable with current quantum processors.

ABSTRACTFatigue cracking is one of the main damage mechanisms that take place in asphalt pavements. However, its evaluation during the design asphalt mixtures is not usually considered due to the [...]

An important measure of the development of quantum computing platforms has been the simulation of increasingly complex physical systems. Before fault-tolerant quantum computing, robust error-mitigation strategies were necessary to continue this growth. Here, we validate recently introduced error-mitigation strategies that exploit the expectation that the ideal output of a quantum algorithm would be a pure state. We consider the task of simulating electron systems in the seniority-zero subspace where all electrons are paired with their opposite spin. This affords a computational stepping stone to a fully correlated model. We compare the performance of error mitigations on the basis of doubling quantum resources in time or in space on up to 20 qubits of a superconducting qubit quantum processor. We observe a reduction of error by one to two orders of magnitude below less sophisticated techniques such as postselection. We study how the gain from error mitigation scales with the system size and observe a polynomial suppression of error with increased resources. Extrapolation of our results indicates that substantial hardware improvements will be required for classically intractable variational chemistry simulations.

ABSTRACT The purpose of this paper is to present an experimental study to characterize the mechanical behaviour of warm mix asphalt (WMA) mixtures designed with Chilean natural zeolite and different [...]

ABSTRACT Microwave heating is regarded as a promising technique to promote crack-healing of asphalt mixtures reinforced with steel wool fibres. In addition to serving as a heat source when subject [...]

Systems of correlated particles appear in many fields of modern science and represent some of the most intractable computational problems in nature. The computational challenge in these systems arises when interactions become comparable to other energy scales, which makes the state of each particle depend on all other particles1. The lack of general solutions for the three-body problem and acceptable theory for strongly correlated electrons shows that our understanding of correlated systems fades when the particle number or the interaction strength increases. One of the hallmarks of interacting systems is the formation of multiparticle bound states2–9. Here we develop a high-fidelity parameterizable fSim gate and implement the periodic quantum circuit of the spin-½ XXZ model in a ring of 24 superconducting qubits. We study the propagation of these excitations and observe their bound nature for up to five photons. We devise a phase-sensitive method for constructing the few-body spectrum of the bound states and extract their pseudo-charge by introducing a synthetic flux. By introducing interactions between the ring and additional qubits, we observe an unexpected resilience of the bound states to integrability breaking. This finding goes against the idea that bound states in non-integrable systems are unstable when their energies overlap with the continuum spectrum. Our work provides experimental evidence for bound states of interacting photons and discovers their stability beyond the integrability limit.

Cryptosporidium parvumand Blastocystis hominisare foodborne parasites known for causing diarrhea. They accumulate in mussels grown on contaminated water bodies, due to the discharge of treated sewage from sewage treatment plants (STP). Despite this, some countries like Chile do not include these parasites in the control or monitoring of sewage water. The objective of this research was to evaluate the contamination of C. parvum. and B. hominisfrom treated sewage (disinfected by chlorination) and Cholga mussels in a touristic rural cove from the bay of Concepción. Cholga mussels from commercial stores and a treated sewage sample were analyzed. Cryptosporidiumspp. was identified by Ziehl-Neelsen-Staining (ZNS) and C. parvumby direct-immunofluorescence assay (IFA) from ZNS-positive samples. Blastocystis hominiswas identified by PCR using locus SSU rDNA. C. parvumand B. hominissubtype ST3 were found in 40% and 45% of Cholga mussel samples, respectively, and both parasites were identified in the treated sewage. Blastocystis hominisSSU rDNA gene alignment from Cholga mussels and treated sewage showed 89% of similarity, indicating that could be the same parasite in both samples. We describe the first evidence of possible contamination with these parasites from treated sewage to Cholga mussel suggesting an environmental contamination with high human risk. Based on these results, further studies will consider all the rural coves and STP from the bay to prevent possible contamination of these parasites.

Little is known about the prognosis of patients with massive pulmonary embolism (PE) and its risk of recurrent venous thromboembolism (VTE) compared with non‐massive PE, which may inform clinical decisions. Our aim was to compare the risk of recurrent VTE, bleeding, and mortality after massive and non‐massive PE during anticoagulation and after its discontinuation. We included all participants in the RIETE registry who suffered a symptomatic, objectively confirmed segmental or more central PE. Massive PE was defined by a systolic hypotension at clinical presentation (<90 mm Hg). We compared the risks of recurrent VTE, major bleeding, and mortality using time‐to‐event multivariable competing risk modeling. There were 3.5% of massive PE among 38 996 patients with PE. During the anticoagulation period, massive PE was associated with a greater risk of major bleeding (subhazard ratio [sHR] 1.72, 95% confidence interval [CI] 1.28–2.32), but not of recurrent VTE (sHR 1.15, 95% CI 0.75–1.74) than non‐massive PE. An increased risk of mortality was only observed in the first month after PE. After discontinuation of anticoagulation, among 11 579 patients, massive PE and non‐massive PE had similar risks of mortality, bleeding, and recurrent VTE (sHR 0.85, 95% CI 0.51–1.40), but with different case fatality of recurrent PE (11.1% versus 2.4%, P= .03) and possibly different risk of recurrent fatal PE (sHR 3.65, 95% CI 0.82–16.24). In this large prospective registry, the baseline hemodynamic status of the incident PE did not influence the risk of recurrent VTE, during and after the anticoagulation periods, but was possibly associated with recurrent PE of greater severity.

AbstractThe goal of this article is the evaluation of the compost quality from Kraft mill organic matter by germination Raphanus sativusand Lepidium sativum.The evaluation of compost was measured in terms of stability, maturity and phytotoxicity. Two compost piles were elaborated, one with a ratio of C/N = 23.67 and the other with C/N = 18.67. Each pile was divided into 2 sections, pile 1 (compost 1 and 2) and pile 2 (compost 3 and 4). Wood bark was added to each pile as a structuring material, resulting in mixtures conformed by treatment sludge with bark. The results obtained show that all the mixtures reached thermophilic temperatures (>50 °C), resulting in stable and mature compost with humic and fulvic acid ratios > 1.9. The gemination index showed no presence of toxic substances, with germination percentages over 80% for all the tests of Raphanus sativusand Lepidium sativum, while the N:P:K ratio of 0.5 of Compost 4 positively and significantly boosted the growth of both species with respect to control. It was concluded that Compost 4, with C/N ratio = 23.67 with structuring material presented positive and significant results (p > 0.05) with respect to Compost 1, 2 and 3.

This article focuses on the speech delivered by the author in Pennsylvania, on November 18, 1991. From Dartmouth to Miami, the author made a firsthand look at the collapse of Pan American in its capital city. Local television devoted a great deal of time to the 7,500 workers suddenly let go, while stunned passengers crowded the ticket counters in order to read the scribbled message: "All Pan American flights canceled." Hence, according to mass media, the emphasis in his speech was on the breakup of the Soviet Union and Yugoslavia, or of anything other than the breakdown, if not breakup, of the United States and its economy.

We present a stream cipher based on a chaotic dynamical system. Using a chaotic trajectory sampled under certain rules in order to avoid any attempt to reconstruct the original one, we create a binary pseudo-random keystream that can only be exactly reproduced by someone that has fully knowledge of the communication system parameters formed by a transmitter and a receiver, sharing the same initial conditions. The plaintext is XOR'ed with the keystream creating the ciphertext, the encrypted message. This keystream passes the NIST's randomness test and has been implemented in a videoconference App for smartphones, in order to show the fast and light nature of the proposed encryption system.

Sludge generation is a drawback of the application of activated sludge (AS) technology in sewage treatment. The reduction of sludge production by the ozonation of an AS system’s mixed liquor is an approach to reduce excess sludge in the process. The aim of this study is to evaluate the application of four ozone doses to mixed liquor fractions from a laboratory-scale AS sewage treatment system. The effect of ozonation in the mixed liquor supernatant was also evaluated. The doses ranged from 0.35 to 0.80 gO3/gVSS. The results show that the applied ozone doses reduced the volatile suspended solids (VSS) concentrations by 25.5%–70.5%, which demonstrates the effectiveness of ozone in reducing the sludge concentration. In the supernatant of the ozonized mixed liquor, the chemical oxygen demand (COD) concentrations increased by 237%, 327%, 597% and 701% after the four doses. Moreover, the total nitrogen and total phosphorus concentrations in the supernatant increased by 9.4%–47% and 9.7%–8.2%, respectively, with respect to a mixed liquor without ozone application. The COD concentration in the effluent is affected by the ozonation. Thus, the COD removal efficiency of the AS system decreased by 6%–63%, whereas the nutrient removal efficiency was constant. In contrast, the specific oxygen uptake rate index was greatly inhibited (maximum inhibition of 31%) after the application of 0.50 gO3/gVSS.

The benefits of a diagnostic workup for occult cancer in patients with VTE are controversial. Our aim was to provide and validate a risk score for occult cancer in patients with VTE.

A comprehensive evaluation of temporal trends in the treatment of patients who have DVT may assist with identification of modifiable factors that contribute to short-term outcomes.

La evaluación del control del asma considera la medición de la sintomatología, la calidad de vida, la función pulmonar y los marcadores inflamatorios. En los últimos años se han multiplicado las publicaciones relacionadas con el estudio de biomarcadores en el manejo del asma pediátrica. A pesar de la gran variedad de marcadores inflamatorios descritos en estudios de investigación, solo un pequeño grupo ha demostrado ser útil en el control de la enfermedad. Los eosinófilos en esputo inducido tienen la evidencia más sólida en la medición del control de asma. El condensado de aire exhalado y los leucotrienos urinarios podrían tener utilidad en el futuro si se logran estandarizar sus procedimientos e interpretación de resultados. El óxido nítrico, la proteína catiónica básica del eosinófilo y la biopsia bronquial con lavado broncoalveolar parecieran tener utilidad solo en un grupo reducido de pacientes.

El síndrome de Rothmund-Thomson (SRT) es un trastorno de herencia autosómica recesiva, con alteraciones endocrino-dermatológicas principalmente. Existen 300 casos a nivel mundial. Solo descrita una gestación.

Objective and design: To quantify the number of mast cells in the skin of rabbits during initiation and progression of the local Shwartzman reaction. Materials: Thirty New Zealand rabbits were divided in two groups (n = 15/group). One group was subjected to the Shwartzman reaction and the other group served as control. Subsequently, animals were further subdivided in six groups of five animals each according to time of euthanasia. Treatments: The local Shwartzman reaction was induced by two inoculations of Salmonella typhimurium lipopolysaccharide. Preparatory inoculation was given intradermally and, 24 h later, the provocative injection was administered intravenously. Controls were subjected to the same procedure but received saline. After provocative injection animals were killed at 1, 8, and 15 days. Methods: Skin samples were fixed in Carnoy’s solution and mast cells were identified employing a low pH toluidine blue stain. Numbers of mast cells were determined per square millimetre and, subsequently, those cells degranulated were identified and quantified to obtain absolute values. A Student’s t test was initially used to compare Shwartzman versus controls at each time point. Subsequently, an ANOVA test employing a factorial experiment was used to assess a possible interaction between time of euthanasia and treatments. Results: The values were transformed (natural logarithms) for appropriate statistical comparisons. Independent comparisons at each time point showed that Shwartzman groups had higher numbers of mast cells than controls at 1 and 8 days, but not at 15 days (5.71 ± 1.00 Vs. 2.40 ± 0.58, P < 0.005; 3.77 ± 0.90 Vs. 2.33 ± 0.56, P < 0. 025, and 2.61 ± 0.25 Vs. 2.39 ± 0.39, P > 0.05, respectively). Degranulated cells were numerous in Shwartzman groups, particularly at day 1 (3.48 ± 0.78) and less obvious at day 8 (0.72 ± 0.50), but were scarce by day 15 (–0.67 ± 0.99) as well as controls (–0.68 ± 0.91). The factorial experiment demonstrated that the Shwartzman reaction and time of euthanasia were independently significant (P < 0.005) but their interaction at day 1 was the major contributor (P < 0.005). Tukey’s w pairwise comparisons of means confirmed that the Shwartzman group killed at day 1 was significantly different from the others (P < 0.05). Conclusions: Mast cells significantly increase in the early stages of the local Shwartzman reaction. Thus, mast cells are a highly dynamic cell population, which have a prominent role during the acute phase of this lipopolysaccharide-induced inflammatory reaction but not during healing.

Abstract.:   The Western Alps are among the best studied collisional belts with both detailed structural mapping and also crustal geophysical investigations such as the ECORS and EGT seismic profile. By contrast, the present-day kinematics of the belt is still largely unknown due to small relative motions and the insufficient accuracy of the triangulation data. As a consequence, several tectonic problems still remain to be solved, such as the amount of N–S convergence in the Occidental Alps, the repartition of the deformation between the Alpine tectonic units, and the relation between deformation and rotation across the Alpine arc. In order to address these problems, the GPS ALPES group, made up of French, Swiss and Italian research organizations, has achieved the first large-scale GPS surveys of the Western Alps. More than 60 sites were surveyed in 1993 and 1998 with a minimum observation of 3 days at each site. GPS data processing has been done by three independent teams using different software. The different solutions have horizontal repeatabilities (N–E) of 4–7 mm in 1993 and 2–3 mm in 1998 and compare at the 3–5-mm level in position and 2-mm/yr level in velocity. A comparison of 1993 and 1998 coordinates shows that residual velocities of the GPS marks are generally smaller than 2 mm/yr, precluding a detailed tectonic interpretation of the differential motions. However, these data seem to suggest that the N–S compression of the Western Alps is quite mild (less than 2 mm/yr) compared to the global convergence between the African and Eurasian plate (6 mm/yr). This implies that the shortening must be accomodated elsewhere by the deformation of the Maghrebids and/or by rotations of Mediterranean microplates. Also, E–W velocity components analysis supports the idea that E–W extension exists, as already suggested by recent structural and seismotectonic data interpretation.

U-Pb age determinations by ion microprobe on zircons from two tuff samples within the Neoproterozoic-early Cambrian successions in Poland are presented. One sample, from the Kaplonosy borehole is within, or conformably below, rocks that contain the Sabellidites-Vendotaenia fossil assemblage of the Upper Vendian. The second sample is from the Książ Wielki IG-1 borehole, from rocks that were referred alternatively to the early Cambrian or to the Vendian on lithostratigraphic evidence.
The Kaplonosy zircons are euhedral and free of visible zircon cores, both optically and as back-scattered electron images, but they exhibit a range in ²⁰⁶Pb/²³⁸U ages that exceeds analytical error. The combined data-set can be resolved into three age-components in different proportions, which overlap in apparent age due to measurement errors. There is a well-defined principal age component at 551±4 Ma (95% limits) and two minor detrital or inherited components at 588±8 Ma and 635±10 Ma. The age of the Kaplonosy tuff is interpreted as equal to that of the youngest and principal component, 551 Ma. This age allows a maximum time difference of 17±4 Ma between the top of the Sławatycze Formation and Lower Cambrian strata of the Heliosphaeridium dissimilare-Skiagia ciliosa acritarch Zone, the latter being time-equivalent to Middle Tommotian strata in northeastern Siberia, recently dated as 534.6±0.5 Ma.
The tuff from the Książ Wielki IG-1 borehole has a similar spectrum of zircon ages, but also contains several detrital grains that have concordant and separate early Proterozoic and Archaean ages. The age of the major component is 549 ± 3 Ma (72% of the total), and there are two older components at 578±9 Ma (13%) and 619 ± 8 Ma (15%). The deposition of the tuff from the Książ Wielki Formation therefore occurred at 549 Ma, indicating that the Książ Wielki Formation is not early Cambrian but Upper Vendian, unless all zircons in the tuff are detrital.

Acritarchs of early Cambrian age occur in strata attributed to the Middle Tommotian in northeastern Siberia. A diagnostic assemblage from a part of the Tyusersk Formation referred to the Dokidocyathus regularis Zone (Middle Tommotian) at Chekurovka, and a much poorer assemblage from Ulakhan-Aldyarkhay, indicate time-equivalence with the Heliosphaeridium dissimilare -Skiagia ciliosa acritarch Zone and the correlative Holmia kjerulfi trilobite Zone in Baltica. The bulk of the species turnover which is part of the Cambrian explosion, including archaeocyathans, small shelly fossils, trilobites and acritarchs, is inferred to occur in the Skiagia ornata-Fimbriaglomerella membranacea (= Schmidtiellus/Rusophycus faunal zone) and H. dissimilare-S. ciliosa (=Holmia kjerulfi trilobite Zone) acritarch zones.

Late Proterozoic and early Phanerozoic phytoplankton comprise a wide array of microfossils of possibly bacterial and algal affinity. Their radiation patterns around the Proterozoic-Cambrian boundary interval are becoming increasingly well-known for numerous sequences in the East European and Siberian Platforms, China, Baltoscandia and North America. Transgressive sequences in the East European Platform and northern Baltoscandia comprise alternating sandstones, mudstones and claystones. Their sedimentology is well documented and microfossils (acritarchs), 'chitinous' fossils (sabelliditids), shelly fossils and trace fossils are well represented. Rocks immediately overlying the transitional beds have yielded lower Cambrian trilobite faunas that are utilized for regional correlations. Continuous successions of planktic microorganisms, consisting of prokaryotic photoautotrophic cyanobacteria and algal protists, are known from rocks comprising the transitional Vendian-Cambrian sequence. In the East European Platform the rock sequence attributed to the lower Cambrian Platysolenites antiquissimus Zone has yielded acritarchs of 'Cambrian type', abruptly replacing a morphologically simple 'Proterozoic type' microbiota recorded in beds of the upper Proterozoic Sabellidites -Vendotaenia Zone. The radiation of novel forms of phytoplankton appears to have been synchronous over a wide part of the late Proterozoic-arly Cambrian shelf, and is parallelled by the nearly contemporaneous emergence of Cambrian shelly fossils and trace fossils. Along with new acritarch taxa, the diagnostic acritarch assemblage of the Platysolenites antiquissimus Zone consists of widely distributed species, occurring also in the lowermost Cambrian deposits of the Siberian Platform, Baltoscandia, Greenland, North America, Svalbard and Scotland. It is suggested that along with shelly faunas, trace fossils and geochemical data, the general radiation patterns of phytoplankton shed light on the events shaping the important biotic events around the Precambrian-Cambrian boundary. It is also believed that a better understanding of the regulatory mechanisms affecting the base of trophic chains may in turn be of significant importance in defining the Precambrian-Cambrian boundary.

Pretreatment of Kraft pulp mill effluents by mycelial pellets or extracellular ligninolytic liquid from Phanerochaete chrysosporiumenhanced the anaerobic degradation of high molecular weight (HMW) compounds up to 79% and 72% respectively, against 45% when only anaerobic digestion was considered. Decolourization was obtained only after fungal pretreatment, since both anaerobic digestion and ligninolytic liquid pretreatment of Kraft effluent slightly increased colour.

AbstractMicrofossils of plant protists called acritarchs occur embedded in, mostly, authigenic chlorite cement in sandstones of the Visings? Group (Upper Proterozoic; southern Sweden). These microfossils are commonly encrusted by a Mn-oxide layer. Similar Mn-oxide was not observed elsewhere in the sandstones, thus suggesting that certain acritarchs have played a role in the transfer and precipitation of Mn in ancient sedimentary environments. In the light of available information on the role of extant protists in biomineralization, possible mechanisms for the precipitation of Mnoxide in the Visings? Group are discussed.

Several large earthquakes occurred in the south of the Sudan in May and July 1990. The focal mechanism solution of the main shock (May 20, 1990), one of the largest events in Africa ever recorded, shows left-lateral strike-slip faulting. One of the nodal planes is parallel to the Aswa fault zone, a major Proterozoic tectonic feature. A line connecting the epicenters of the main events of May and July also strikes in the same direction. Field observations and satellite imagery also indicate left-lateral horizontal reactivation movement along this large structural feature during Cenozoic times. The fault plane solutions of the Harvard Centroid Moment Tensor catalog for earthquakes between 1977 and 1989 in the East African Rift System show extensional horizontal slip component striking about northwest-southeast. All these facts lead the interpretation of this wide, diffuse fault zone as an active intracontinental transform area linking the two main branches of the rift system. If one considers this displacement and the slip directions obtained from the centroid moment tensors solutions as characterizing the motion between the Nubian and Somalian plates, new constraints on the regional geodynamics can be inferred; the Somalian block appears to be moving southeastwards relative to the African block.

AbstractAn Ediacaran assemblage dominated by an unidentified species of CyclomedusaSprigg 1947, along with species of Ediacaria?Sprigg 1947, BeltanellaSprigg 1947, HiemaloraFedonkin 1982, and Nimbia?Fedonkin 1980, is described for the first time from the Innerelv Member of the Stappogiedde Formation exposed in coastal outcrops west of Tanafjorden on Digermul Peninsula, in northeastern Finnmark, northern Norway. The fossil assemblage is dominated by discoidal forms which share certain affinities with the cosmopolitan genera. Cyclomedusaand Ediacaria. However, our specimens differ from these and other discoidal Ediacaran fossils in the absence of radial sculpture. This, along with a basically concentric organization, are characteristics shared with Kullingiafrom the Dividal Group of northern Scandinavia, the White Sea, Podolia, and northwestern Canada, along with undescribed discoidal remains from the Charnian Supergroup, Charnwood Forest, Leicestershire, England, and the Conception Group, Avalon Peninsula, Newfoundland.Our discovery of an Ediacaran-type assemblage within the Middle Innerelv Member provides support for previous suggestions of a late Vendian age for this sequence. This general conclusion is consistent with the occurrence of early Cambrian taxa, including the trace fossil Phycodes, and the problematical forms Vendotaeniaand Sabellidites,in basal portions of the Lower Breivik Formation, within the same stratigraphie section. The lowest formally-proposed faunal zone in northern Scandinavia is the KullingiaZone, based on the occurrence of the fossil medusoid Kullingia concentricain Member III (Middle Sandstone C) of the Dividal Group, northern Scandinavia. Kullingiais a distinctly chambered form that was probably pelagic. In contrast, Cyclomedusa,and related genera of the so-called Cyclomedusaplexus, comprise an informal grouping of intergrading, probably benthic, taxa that possess radial and/or concentric organization. In light of the intergradational nature of taxa, present difficulties in taxonomic interpretation and correlation, and the abundance of cyclomedusoids in many Ediacaran assemblages, we suggest that the concept of the KullingiaZone, as originally defined for northern Scandanavia, be broadened to include the common form genera of the Cyclomedusaplexus, inclusive of the occurrences in the Innerelv Member described herein. It is our hope that additional fieldwork will provide a basis for more refined taxonomic evaluations and biozonation.

A polyclonal antiserum raised in sheep against human cathepsin B was tested for specificity and cross-reactivity with the horse homologue by SDS-PAGE and Western blotting, prior to being used for immunolocalization of the enzyme in equine articular cartilage. In Western blots, the antiserum recognized the 30 kDa single chain and 25 kDa heavy chain of the mature enzyme in purified bovine cathepsin B, and corresponding bands at 32 and 27 kDa in equine chondrocyte and fibroblast lysates. This antiserum was then used to compare the expression and distribution of cathepsin B in normal and dyschondroplastic cartilage of young horses. In normal articular cartilage (n=6 animals), significant amounts of enzyme were detected only in hypertrophicchondrocytes in the deep zone. The enzyme was intracellular, located in the lysosomal granules. No extracellular matrix staining was observed. Levels of cathepsin B were increased slightly above normal in the deep zone in age-matched dyschondroplastic cartilage (n=5 animals). The most striking finding, however, was the abundance of the enzyme in chondrocyte clonal clusters associated with the lesions. Cathepsin B levels were low in chondrocytes isolated from normal cartilage (n=6), but increased progressively during serial subculture, reaching a maximum at passage 5-6. In contrast, primary cultures of dyschondroplastic chondrocytes (n=3) expressed abundant cathepsin B.

Venous thromboembolism (VTE) is a major cause of morbidity and mortality postoperatively. The use of pharmacologic prophylaxis is effective in reducing the incidence of VTE. However, the prophylaxis is often discontinued at hospital discharge, especially for those with benign disease. The implications of this practice are not known. We assessed the data from a large, ongoing registry regarding the time course of VTE and outcomes after noncancer surgery.

Overlap exists between the risk factors for coronary artery disease and venous thromboembolism (VTE). However, a paucity of data is available on the incidence of major acute cardiovascular events (MACE) and major adverse limb events (MALE) among patients presenting with VTE. Moreover, it is unknown whether the rate of cardiovascular outcomes differs among patients with unprovoked vs provoked VTE.

PurposeMultiphase CTA (MCTA) has recently been advocated as an acceptable alternative to whole brain CT perfusion (CTP) for identifying patients with intracranial large vessel occlusion (LVO) who may benefit from thrombectomy (1). Our institution recently transitioned from CTP to MCTA for triage of acute stroke patients. The purpose of this study is to identify predictors of collateral scores and evaluate the likelihood of undergoing intervention based on these scores.Materials and MethodsThe imaging database was queried for all patients who underwent MCTA from August 2016 through March 2017. Rates and locations of large vessel occlusions, collateral scores, rates of thrombectomy, and TICI scores were reviewed. Several comorbidities/risk factors were reviewed.Results84 out of 238 patients who underwent MCTA were found to have intracranial LVO, with 48 patients subsequently undergoing thrombectomy. Table 1 shows rates of thrombectomy by collateral score. Risk factor analysis showed that patients who were transferred had a statistically significant likelihood of having poor collateral scores (p=0.018).Abstract E-038 Table 1 Rate of Thrombectomy by Collateral ScoreCollateral ScoreTotalThrombectomy% Taken For ThrombectomyNot Assessed 17 5 29 0 1 0 0 1 3 0 0 2 7 1 14 3 17 9 53 4 28 24 86 5 11 9 82 ConclusionCollateral scores of 4 and 5 have over 80% rate of inclusion for thrombectomy in the setting of a large vessel occlusion. Transfer of patients is correlated with statistically significant poorer collateral scores.Reference. Menon BK, d’Esterre CD, Qazi EM, et al. Multiphase CT Angiography: A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke. Radiology2015May; 275(2):510–20DisclosuresG. Bennett:None. S. Arndt:None. J. Lavie:None. A. Albar:None. G. Vidal:3; C; Penumbra. J. Milburn:3; C; Penumbra.

We sought to determine the risk factors for subsequent bleeding and recurrent venous thromboembolism (VTE) events following isolated noncatheter-associated upper extremity deep venous thrombosis (non-CA-UEDVT) to better inform future treatment decisions for this group of patients.

IntroductionMultiple recent randomized clinical trials have demonstrated the efficacy of endovascular thrombectomy in patients with acute stroke involving the proximal anterior circulation, and multiple clinical factors influence the outcome of patients undergoing thrombectomy. Obesity, despite its adverse health effects in the general population, has been associated with improved clinical outcomes in cardiovascular disease, including stroke--this phenomenon has been referred to the “obesity paradox”.1–3To our knowledge, this “obesity paradox” has not been studied in patients undergoing endovascular stroke treatment. This study examines the role of body mass index (BMI) in outcomes of patients with strokes involving the anterior circulation who undergo mechanical thrombectomy.Materials and MethodsThe CT perfusion database was queried for all patients evaluated for thrombectomy at our comprehensive stroke center from 2012–2015; 133 patients with large vessel occlusions of the anterior circulation who underwent thrombectomy with BMI available in the electronic medical record were identified. Patients were stratified into 5 BMI categories: underweight (UW; BMI<18.5kg/m2), normal weight (NW; BMI 18.5–24.99 kg/m2), overweight (OW; BMI 25–29.99 kg/m2), obese (Ob; BMI 30–39.99 kg/m2), and morbidly obese (MO; BMI≥40 kg/m2). Univariate analysis was performed assessing the relationship between various BMI categories and discharge NIHSS and change in NIHSS after treatment.ResultsMO had the lowest discharge NIHSS of all BMI groups with mean discharge NIHSS of 2.1. Both UW and MO patients had statistically lower discharge NIHSS than the cohort of NW, OW, and Ob patients (p=0.032 for UW and p=0.0045 for MO, respectively). MO had greater improvement in NIHSS after treatment compared to NW, OW, and Ob patients (NIHSS change 15.0 vs 6.5, p=0.021). UW patients had greater improvement in NIHSS after treatment than NW, OW, and OB patients, but this was not statistically significant.ConclusionExtremes of BMI were associated with better clinical outcomes with a “reverse U-shaped relationship” in patients with large vessel occlusions of the anterior circulation undergoing endovascular treatment, as the best clinical outcomes were observed in the UW and MO. This paradox differs from the previously described “obesity paradox,” in which OW and mildly Ob typically have better outcomes than the NW, UW, and MO.1,2The cause of and implications for these findings in acute stroke treatment is unclear. While these results may be secondary to patient selection bias, additional potential mechanisms include possible associations between body composition and stroke etiology, clot composition, and collateral vessels. Further investigation into this possible new paradox and potential associations between BMI and other factors influencing endovascular treatment outcomes is warranted.References. Lavie, Carl J., Richard V. Milani, and Hector O. Ventura. ”Obesity and cardiovascular disease.”Journal of the American College of Cardiology 53.21 (2009): 1925–1932.. Andersen, Klaus Kaae, and Tom Skyhøj Olsen. ”The obesity paradox in stroke: lower mortality and lower risk of readmission for recurrent stroke in obese stroke patients.”International Journal of Stroke 10.1 (2015): 99–104.. Kim, Beom Joon, et al. ”Dynamics of obesity paradox after stroke, related to time from onset, age, and causes of death.”Neurology 79.9 (2012): 856–863.DisclosuresJ. Lavie:None. G. Bennett:None. S. Arndt:None. A. Albar:None. K. Wojcik:None. J. Milburn:None. G. Vidal:None.

Patients with acute venous thromboembolism (VTE) are at increased risk for the development of subsequent arterial ischemic events unrelated to the diagnosis of VTE. Accurate identification of VTE patients at increased risk for ischemic events during the course of anticoagulation may help to select those who would potentially benefit from concomitant therapy with anticoagulants and antiplatelets.