Alternate Cervical Venous Access Sites for Implantable Port Catheters: Experience at a Single Quaternary Care Institution.

INTRODUCTION: Clinical outcomes of implantable port catheters (IPCs) placed via alternative veins such as the external jugular and cervical collaterals have not been well established. This investigation evaluates the short- and long-term outcomes of IPCs inserted via alternate cervical veins (ACV) compared to traditionally inserted IPCs via the internal jugular vein (IJV). MATERIALS AND METHODS: A total of 24 patients who received an IPC between 2010 and 2020 via an ACV-defined as the external jugular vein, superficial cervical vein, or unnamed collateral veins-were identified. Based on power analysis, a matched control group of 72 patients who received IPCs via the IJV was identified. Non-inferiority analysis for port complications was performed between the two groups based on the selected non-inferiority margin of 20%. Secondary end points included complication-free survival and comparison of complications by the time at which they occurred. RESULTS: ACV access was non-inferior to traditional access for overall complications. Alternate access resulted in fewer complications than traditional access with an estimated reduction of - 7.0% [95% CI - 23.6%, 39.7%]. There was no significant difference in peri-procedural and post-procedural complications between the two groups. Complication-free survival was also equivalent between the two groups. CONCLUSION: IPC placement via ACVs was non-inferior to IPCs placed via traditional access through the IJV. When abnormal pathology obviates the use of IJV access, other cervical veins may be considered prior to seeking alternate locations such as femoral, translumbar, inferior vena cava, and hepatic veins.

Subclavian Effort Thrombosis: Pathophysiology, Diagnosis, and Management.

Subclavian vein (SCV) effort thrombosis, also known as Paget-Schroetter syndrome or venous thoracic outlet syndrome, is an uncommon condition that affects individuals with an irregularly narrow thoracic outlet who engage in repetitive overhead motions of the affected arm. Venous injury arises from microtraumas that occur from the repetitive compression of the SCV between the first rib and the overlying clavicle. Additional sources of extrinsic compression can be due to the anterior scalene muscle, subclavius muscle, and costoclavicular ligament. SCV effort thrombosis is a distinct entity from other forms of deep venous thrombosis and requires unique diagnostic and treatment considerations. Early catheter-directed therapy in the form of pharmacomechanical or catheter-directed thrombolysis combined with prompt surgical thoracic outlet decompression offers patients the best chances for early and durable symptom relief.

Erratum: Subclavian Effort Thrombosis: Pathophysiology, Diagnosis, and Management.

[This corrects the article DOI: 10.1055/s-0042-1753481.].

Photoredox-Mediated, Nickel-Catalyzed Trifluoromethylthiolation of Aryl and Heteroaryl Iodides.

While trifluoromethylthiolation of aryl halides has been extensively explored, the current methods require complex and/or air-sensitive catalysts. Reported here is a method employing a bench-stable Ni(II) salt and an iridium photocatalyst that can mediate the trifluoromethylthiolation of a wide range of electronically diverse aryl and heteroaryl iodides, likely via a Ni(I)/Ni(III) catalytic cycle. The reaction has broad functional group tolerance and potential for application in medicinal chemistry, as demonstrated by a late-stage functionalization approach to access (racemic)-Monepantel.

Partnership Between a Federal Agency and 4 Tribal Nations to Improve COVID-19 Response Capacities.

Upon request from tribal nations, and as part of the Centers for Disease Control and Prevention's (CDC's) emergency response, CDC staff provided both remote and on-site assistance to tribes to plan, prepare, and respond to the COVID-19 pandemic. From April 2, 2020, through June 11, 2021, CDC deployed a total of 275 staff to assist 29 tribal nations. CDC staff typically collaborated in multiple work areas including epidemiology and surveillance (86%), contact tracing (76%), infection prevention control (72%), community mitigation (72%), health communication (66%), incident command structure (55%), emergency preparedness (38%), and worker safety (31%). We describe the activities of CDC staff in collaboration with 4 tribal nations, Northern Cheyenne, Hoopa Valley, Shoshone-Bannock, and Oglala Sioux Tribe, to combat COVID-19 and lessons learned from the engagement.

A Survey of Interventional Radiologists Regarding the Use of Morbidity and Mortality Conferencing in Departmental Quality Improvement Programs.

PURPOSE: To investigate the degree to which morbidity and mortality (M&M) conferencing is utilized in interventional radiology (IR), identify impediments to its adoption, and assess the experience of those using this tool. MATERIALS AND METHODS: Members of the Society of Interventional Radiology (SIR) were offered a 9-question survey of practices and experiences regarding M&M conferencing within their quality assessment (QA) programs. RESULTS: Among 604 respondents, 37.8% were university-based practitioners and 60% were from outside of university practices. Of all respondents, 43% reported practicing 100% IR, with 28.5% practicing IR 75%-99% and 11% practicing IR <50% of the time. The use of M&M conferencing was significantly greater in university practices (90.7%) than in nonuniversity practices (37.1%) and among practitioners performing at least 75% IR (71.2%) than among those practicing <75% (28.8%). The conferences were held monthly (66.6%) or more often, and the majority (56%) of the events identified were scored using the SIR severity score. Approximately 20% of M&M conferences were multidisciplinary, shared most commonly with vascular surgery. The reasons cited for not using M&M included the lack of time and the logistical challenges of the process. However, among those who participate in M&M conferences, the QA goals of the conference were met at very high rates. CONCLUSIONS: M&M conferencing is well established in university IR programs and among full-time practitioners but much less so elsewhere. For those sites that do not utilize M&M conferencing, there may be a considerable benefit to addressing the obstacles that are limiting their implementation of this tool.

Gold-Catalyzed Post-Polymerization Modification of Commodity Aromatic Polymers.

Synthetic aromatic polymers are ubiquitous and indispensable to modern life, industry, and the global economy. The direct functionalization of these materials remains a considerable challenge on account of their unreactive aromatic C-H bonds and robust physical properties. Here, we demonstrate that homogeneous gold catalysis offers a mild, chemoselective, and practical approach to functionalize high-volume commodity aromatic polymers. Utilizing a gold-catalyzed intermolecular hydroarylation between a methyl ester functionalized alkyne, methyl propiolate, and nucleophilic arenes within polystyrene (PS) results in direct functionalization of phenyl rings with 1,2-substituted methyl acrylate functional groups. The reactivity and functionalization depend on the steric and electronic environment of the catalyst, counterion pairing, and method of activation. The reactivity is broad in scope, enabling the functionalization of arenes within commercial polysulfone (PSU) and waste polyethylene terephthalate (PET). These reactions open new opportunities to chemically transform aromatic polymers and modify their physical properties.

Gold-Catalyzed C-H Functionalization Polycondensation for the Synthesis of Aromatic Polymers.

Homogeneous gold (Au) complexes have demonstrated tremendous utility in modern organic chemistry; however, their application for the synthesis of polymers remains rare. Herein, we demonstrate the first catalytic application of Au complexes toward the polycondensation of alkyne-containing comonomers and heteroarene nucleophiles. Polymerization occurs through successive intermolecular hydroarylation reactions to produce high molecular weight aromatic copolymers with 1,1-disubstituted alkene backbone linkages. Clear correlations between the rate and degree of polymerization (DP) were established based on catalyst structure and counterion pairing, thus enabling polymerization reactions that proceeded with remarkable efficiency, high reactivity, and exceptional DPs. The reactivity is broad in scope, enabling the copolymerization of highly functionalized aromatic and aliphatic monomers. These results highlight the untapped utility of Au catalysis in providing access to new macromolecular constructs.

Water Table Dynamics and Biogeochemical Cycling in a Shallow, Variably-Saturated Floodplain.

Three-dimensional variably saturated flow and multicomponent biogeochemical reactive transport modeling, based on published and newly generated data, is used to better understand the interplay of hydrology, geochemistry, and biology controlling the cycling of carbon, nitrogen, oxygen, iron, sulfur, and uranium in a shallow floodplain. In this system, aerobic respiration generally maintains anoxic groundwater below an oxic vadose zone until seasonal snowmelt-driven water table peaking transports dissolved oxygen (DO) and nitrate from the vadose zone into the alluvial aquifer. The response to this perturbation is localized due to distinct physico-biogeochemical environments and relatively long time scales for transport through the floodplain aquifer and vadose zone. Naturally reduced zones (NRZs) containing sediments higher in organic matter, iron sulfides, and non-crystalline U(IV) rapidly consume DO and nitrate to maintain anoxic conditions, yielding Fe(II) from FeS oxidative dissolution, nitrite from denitrification, and U(VI) from nitrite-promoted U(IV) oxidation. Redox cycling is a key factor for sustaining the observed aquifer behaviors despite continuous oxygen influx and the annual hydrologically induced oxidation event. Depth-dependent activity of fermenters, aerobes, nitrate reducers, sulfate reducers, and chemolithoautotrophs (e.g., oxidizing Fe(II), S compounds, and ammonium) is linked to the presence of DO, which has higher concentrations near the water table.

Magnetostrophic balance as the optimal state for turbulent magnetoconvection.

The magnetic fields of Earth and other planets are generated by turbulent convection in the vast oceans of liquid metal within them. Although direct observation is not possible, this liquid metal circulation is thought to be dominated by the controlling influences of planetary rotation and magnetic fields through the Coriolis and Lorentz forces. Theory famously predicts that planetary dynamo systems naturally settle into the so-called magnetostrophic state, where the Coriolis and Lorentz forces partially cancel, and convection is optimally efficient. Although this magnetostrophic theory correctly predicts the strength of Earth's magnetic field, no laboratory experiments have reached the magnetostrophic regime in turbulent liquid metal convection. Furthermore, computational dynamo simulations have as yet failed to produce a magnetostrophic dynamo, which has led some to question the existence of the magnetostrophic state. Here, we present results from the first, to our knowledge, turbulent, magnetostrophic convection experiments using the liquid metal gallium. We find that turbulent convection in the magnetostrophic regime is, in fact, maximally efficient. The experimental results clarify these previously disparate results, suggesting that the dynamically optimal magnetostrophic state is the natural expression of turbulent planetary dynamo systems.

An allele of sequoia dominantly enhances a trio mutant phenotype to influence Drosophila larval behavior.

The transition of Drosophila third instar larvae from feeding, photo-phobic foragers to non-feeding, photo-neutral wanderers is a classic behavioral switch that precedes pupariation. The neuronal network responsible for this behavior has recently begun to be defined. Previous genetic analyses have identified signaling components for food and light sensory inputs and neuropeptide hormonal outputs as being critical for the forager to wanderer transition. Trio is a Rho-Guanine Nucleotide Exchange Factor integrated into a variety of signaling networks including those governing axon pathfinding in early development. Sequoia is a pan-neuronally expressed zinc-finger transcription factor that governs dendrite and axon outgrowth. Using pre-pupal lethality as an endpoint, we have screened for dominant second-site enhancers of a weakly lethal trio mutant background. In these screens, an allele of sequoia has been identified. While these mutants have no obvious disruption of embryonic central nervous system architecture and survive to third instar larvae similar to controls, they retain forager behavior and thus fail to pupariate at high frequency.

On the genesis of the Earth's magnetism.

Few areas of geophysics are today progressing as rapidly as basic geomagnetism, which seeks to understand the origin of the Earth's magnetism. Data about the present geomagnetic field pours in from orbiting satellites, and supplements the ever growing body of information about the field in the remote past, derived from the magnetism of rocks. The first of the three parts of this review summarizes the available geomagnetic data and makes significant inferences about the large scale structure of the geomagnetic field at the surface of the Earth's electrically conducting fluid core, within which the field originates. In it, we recognize the first major obstacle to progress: because of the Earth's mantle, only the broad, slowly varying features of the magnetic field within the core can be directly observed. The second (and main) part of the review commences with the geodynamo hypothesis: the geomagnetic field is induced by core flow as a self-excited dynamo. Its electrodynamics define 'kinematic dynamo theory'. Key processes involving the motion of magnetic field lines, their diffusion through the conducting fluid, and their reconnection are described in detail. Four kinematic models are presented that are basic to a later section on successful dynamo experiments. The fluid dynamics of the core is considered next, the fluid being driven into motion by buoyancy created by the cooling of the Earth from its primordial state. The resulting flow is strongly affected by the rotation of the Earth and by the Lorentz force, which alters fluid motion by the interaction of the electric current and magnetic field. A section on 'magnetohydrodynamic (MHD) dynamo theory' is devoted to this rotating magnetoconvection. Theoretical treatment of the MHD responsible for geomagnetism culminates with numerical solutions of its governing equations. These simulations help overcome the first major obstacle to progress, but quickly meet the second: the dynamics of Earth's core are too complex, and operate across time and length scales too broad to be captured by any single laboratory experiment, or resolved on present-day computers. The geophysical relevance of the experiments and simulations is therefore called into question. Speculation about what may happen when computational power is eventually able to resolve core dynamics is given considerable attention. The final part of the review is a postscript to the earlier sections. It reflects on the problems that geodynamo theory will have to solve in the future, particularly those that core turbulence presents.

Turbulent convection in liquid metal with and without rotation.

The magnetic fields of Earth and other planets are generated by turbulent, rotating convection in liquid metal. Liquid metals are peculiar in that they diffuse heat more readily than momentum, quantified by their small Prandtl numbers, Pr << 1. Most analog models of planetary dynamos, however, use moderate Pr fluids, and the systematic influence of reducing Pr is not well understood. We perform rotating Rayleigh-Bénard convection experiments in the liquid metal gallium (Pr = 0.025) over a range of nondimensional buoyancy forcing (Ra) and rotation periods (E). Our primary diagnostic is the efficiency of convective heat transfer (Nu). In general, we find that the convective behavior of liquid metal differs substantially from that of moderate Pr fluids, such as water. In particular, a transition between rotationally constrained and weakly rotating turbulent states is identified, and this transition differs substantially from that observed in moderate Pr fluids. This difference, we hypothesize, may explain the different classes of magnetic fields observed on the Gas and Ice Giant planets, whose dynamo regions consist of Pr < 1 and Pr > 1 fluids, respectively.

Thermal evidence for Taylor columns in turbulent rotating Rayleigh-Bénard convection.

We investigate flow structures in rotating Rayleigh-Bénard convection experiments in water using thermal measurements. We focus on correlations between time series measurements of temperature in the top and bottom boundaries. Distinct anticorrelations are observed for rapidly rotating convection, which are argued to attest to heat transport by convective Taylor columns. In support of this argument, these quasigeostrophic flow structures are directly observed in flow visualizations, and their thermal signature is qualitatively reproduced by a simple model of heat transport by columnar flow. Weakly rotating and nonrotating convection produces positively correlated temperature changes across the layer, indicative of heat transport by large-scale circulation. We separate these regimes using a transition parameter that depends on the Rayleigh and Ekman numbers, RaE3/2.

Genome characteristics of a generalist marine bacterial lineage.

Members of the marine Roseobacter lineage have been characterized as ecological generalists, suggesting that there will be challenges in assigning well-delineated ecological roles and biogeochemical functions to the taxon. To address this issue, genome sequences of 32 Roseobacter isolates were analyzed for patterns in genome characteristics, gene inventory, and individual gene/pathway distribution using three predictive frameworks: phylogenetic relatedness, lifestyle strategy and environmental origin of the isolate. For the first framework, a phylogeny containing five deeply branching clades was obtained from a concatenation of 70 conserved single-copy genes. Somewhat surprisingly, phylogenetic tree topology was not the best model for organizing genome characteristics or distribution patterns of individual genes/pathways, although it provided some predictive power. The lifestyle framework, established by grouping isolates according to evidence for heterotrophy, photoheterotrophy or autotrophy, explained more of the gene repertoire in this lineage. The environment framework had a weak predictive power for the overall genome content of each strain, but explained the distribution of several individual genes/pathways, including those related to phosphorus acquisition, chemotaxis and aromatic compound degradation. Unassembled sequences in the Global Ocean Sampling metagenomic data independently verified this global-scale geographical signal in some Roseobacter genes. The primary findings emerging from this comparative genome analysis are that members of the lineage cannot be easily collapsed into just a few ecologically differentiated clusters (that is, there are almost as many clusters as isolates); the strongest framework for predicting genome content is trophic strategy, but no single framework gives robust predictions; and previously unknown homologs to genes for H(2) oxidation, proteorhodopsin-based phototrophy, xanthorhodpsin-based phototrophy, and CO(2) fixation by Form IC ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) expand the possible mechanisms for energy and carbon acquisition in this remarkably versatile bacterial lineage.

Boundary layer control of rotating convection systems.

Turbulent rotating convection controls many observed features of stars and planets, such as magnetic fields, atmospheric jets and emitted heat flux patterns. It has long been argued that the influence of rotation on turbulent convection dynamics is governed by the ratio of the relevant global-scale forces: the Coriolis force and the buoyancy force. Here, however, we present results from laboratory and numerical experiments which exhibit transitions between rotationally dominated and non-rotating behaviour that are not determined by this global force balance. Instead, the transition is controlled by the relative thicknesses of the thermal (non-rotating) and Ekman (rotating) boundary layers. We formulate a predictive description of the transition between the two regimes on the basis of the competition between these two boundary layers. This transition scaling theory unifies the disparate results of an extensive array of previous experiments, and is broadly applicable to natural convection systems.

Photomodulated chiral induction in helical azobenzene oligomers.

Appending L-alanine to the terminal positions of a helical azobenzene oligomer produced a P helical bias, which increased with oligomer length. Irradiation gave rise to E-->Z isomerization of the terminal azo linkages, which displaced the stereogenic center of L-Ala from the helix backbone and suppressed chiral induction. Theoretical simulations of the CD spectrum of the P helical conformation are in qualitative agreement with the experimental spectra.

Rapid detection of human fecal contamination in estuarine environments by PCR targeting of Bifidobacterium adolescentis.

Detection of Bifidobacterium adolescentis was used as an effective genetic marker of human fecal contamination in Georgia estuaries. Enterococci enumerations on mEI media indicated that a tributary to the Little Satilla River with 516 CFU/100 ml was the most polluted of all the rivers tested. Extracted DNA from eight river water samples was subjected to a two-step nested PCR protocol using genus and species specific primers for Bifidobacterium spp. and B. adolescentis. B. adolescentis was detected from extracted DNA in Dunbar River, Black Bank Creek, and in a Little Satilla River tributary which demonstrates the presence of human fecal contamination in these three rivers. In the five other estuaries tested including West Point-Federica River and the Altamaha River, which both had less than 16 CFU/100 ml of enterococci, B. adolescentis was not detected.