High Mass Density Research Articles

Diagnosis, characteristics, and treatment of breast carcinomas within benign fibroepithelial tumors.

Breast carcinoma arising in a benign fibroepithelial tumor is rare, and is usually discovered incidentally during examination of the breast mass. We evaluated the clinicopathological features, treatment, and prognosis of seven women with breast carcinomas within benign fibroepithelial tumors, diagnosed and treated at a single institution between 2011 and 2015. Seven women, aged 21-64years, visited our hospital complaining of a breast mass detected by self-checking or screening examination. All patients had well-demarcated movable breast masses. Ultrasonography showed circumscribed masses suggesting benign tumors in all cases, and mammography revealed well-defined, high-density masses, with or without calcification. The masses progressed in two patients. A preoperative histological diagnosis of carcinoma was made following needle biopsy in four patients. Tumorectomy, breast-conserving surgery, and mastectomy were performed in three, two, and two patients, respectively. One patient underwent lymph node dissection and another underwent sentinel node biopsy. Histologically, the masses were diagnosed as invasive ductal carcinoma, ductal carcinoma in situ or lobular carcinoma in situ, arising in a benign phyllodes tumor, fibroadenoma, or fibroadenomatoid mastopathy. Lymph node metastasis was detected in two patients. There was no recurrence in any of the patients. Although a carcinoma within a preexisting benign fibroepithelial tumor is extremely rare, it is important to be aware of the possibility of invasive and metastatic disease.

Ossified extradural en-plaque meningioma of the cervical spine

A 57-year-old woman sustained gradually progressive sensorimotor disturbance in the left upper extremity for one year. Neurological examination found a diminished sensation below the left C7 dermatome and reduced strength in the left interosseous muscles. Computed tomography of the cervical spine revealed a high density mass at C7, in the left dorsal part of the spinal canal. Magnetic resonance imaging found an enhancing, en-plaque tumor at C6-T1, involving a non-enhancing part, and considerable compression of the spinal cord. The patient underwent tumor resection through hemilaminectomy of C5-C7. The tumor was located epidurally, highly fibrous including bony-hard parts, and severely adhered to the dura mater that necessitated drilling for debulking. A subtotal resection was achieved and histological diagnosis was a fibrous meningioma with metaplastic ossification. Ossification may be a pathognomonic appearance of spinal extradural meningiomas that makes resection maneuvers difficult.

Understanding caustic crossings in giant arcs: Characteristic scales, event rates, and constraints on compact dark matter

The recent discovery of fast transient events near critical curves of massive galaxy clusters, which are interpreted as highly magnified individual stars in giant arcs due to caustic crossing, opens up the possibility of using such microlensing events to constrain a range of dark matter models such as primordial black holes and scalar field dark matter. Based on a simple analytic model, we study lensing properties of a point mass lens embedded in a high magnification region, and derive the dependence of the peak brightness, microlensing time scales, and event rates on the mass of the point mass lens as well as the radius of a source star that is magnified. We find that the lens mass and source radius of the first event MACS J1149 Lensed Star 1 (LS1) are constrained, with the lens mass range of $0.1~M_\odot \lesssim M \lesssim 4\times 10^3M_\odot$ and the source radius range of $40~R_\odot \lesssim R \lesssim 260~R_\odot$. In the most plausible case with $M\approx 0.3~M_\odot$ and $R\approx 180~R_\odot$, the source star should have been magnified by a factor of $\approx 4300$ at the peak. The derived lens properties are fully consistent with the interpretation that MACS J1149 LS1 is a microlensing event produced by a star that contributes to the intra-cluster light. We argue that compact dark matter models with high fractional mass densities for the mass range $10^{-5}M_\odot \lesssim M\lesssim 10^2M_\odot$ are inconsistent with the observation of MACS J1149 LS1 because such models predict too low magnifications. Our work demonstrates a potential use of caustic crossing events in giant arcs to constrain compact dark matter.

MR Imaging Features of Tubular Carcinoma: Preliminary Experience in Twelve Masses.

We retrospectively analyzed the magnetic resonance (MR) imaging features and diffusion-weighted imaging findings of the 12 masses of 10 patients with tubular carcinoma (TC), including mammography and sonography findings. Mammographic, sonographic and magnetic resonance imaging features in 12 histopathologically confirmed masses diagnosed as TC of the breast within 10 patients were evaluated. Morphologic characteristics, enhancement features, apparent diffusion coefficient (ADC) values were reviewed. On mammography (n=5), TC appeared as high density masses with indistinct, spiculated or obscured margins. Sonographically, TC appeared as a hypoechoic appearance (n=12) with posterior acoustic shadowing in nine. On MR imaging, the margins of ten of twelve masses were irregular. Internal enhancement patterns were heterogeneous in 10 patients. Dynamic enhancement patterns illustrated plateau kinetics (n=8). On the T2-weighted images 4 masses were hypointense, and 8 were hyperintense; hypointense internal septation was found in seven of these. Tubular carcinoma appeared as hyperintense on diffusion-weighted imaging with ADC values of 0.85±0.16×10-3 mm2/s that was lower than the normal parenchyma of 1.25±0.25×10-3 mm2/s. According to our study with a limited number of cases, tubular carcinomas can be described as hyperintense breast carcinomas with or without dark internal septation like appearance on T2-weighted images. Low ADC values from DW imaging can be used to differentiate TC from hyperintense benign breast lesions.

On the Effect of Re Addition on Microstructural Evolution of a CoNi-Based Superalloy

In this study, the effect of rhenium (Re) addition on microstructural evolution of a new low-density Co-Ni-Al-Mo-Nb based superalloy is presented. Addition of Re significantly influences the γ' precipitate morphology, the γ/γ' lattice misfit and the γ/γ' microstructural stability during long term aging. An addition of 2 at.% Re to a Co-30Ni-10Al-5Mo-2Nb (all in at.%) alloy, aged at 900°C for 50 hours, reduces the γ/γ' lattice misfit by ~ 40% (from 0.32% to 0.19%, measured at room temperature) and hence alters the γ' morphology from cuboidal to round-cornered cuboidal precipitates. The composition profiles across the γ/γ' interface by atom probe tomography (APT) reveals Re partitions to the γ' phase (KRe=0.34) and also results in the partitioning reversal of Mo to the γ' phase (KMo=0.90) from the γ' precipitate. An inhomogeneous distribution of Gibbsian interfacial excess for the solute Re (ΓRe, ranging from 0.8 to 9.6 atom.nm-2) has been observed at the γ/γ' interface. Coarsening study at 900°C (up to 1000 hours) suggests that the coarsening of γ' precipitates occurs solely by an evaporation-condensation (EC) mechanism. This is contrary to that observed in the Co-30Ni-10Al-5Mo-2Nb alloy as well as in some of the Ni-Al based and high mass density Co-Al-W based superalloys, where γ' precipitates coarsens by coagulation/coalescence mechanism with extensive alignment of γ' along directions as a sign of microstructural instability. The γ' coarsening rate exponent (Kr) and γ/γ' interfacial energy are estimated to be 1.41 x 10-27 (m3/s) and 8.4 mJ/m2, that are comparable and lower than Co-Al-W based superalloys respectively.

Ultralight Angstrom-Scale Optimal Optical Reflectors

High reflectance in many state-of-the-art optical devices is achieved with noble metals. However, metals are limited by losses and, for certain applications, by their high mass density. Using a combination of ab initio and optical transfer matrix calculations, we evaluate the behavior of graphene-based angstrom-scale metamaterials and find that they could act as nearly perfect reflectors in the mid–long-wave infrared (IR) range. The low density of states for electron–phonon scattering and interband excitations leads to unprecedented optical properties for graphene heterostructures, especially alternating atomic layers of graphene and hexagonal boron nitride, at wavelengths greater than 10 μm. At these wavelengths, these materials exhibit reflectivities exceeding 99.7% at a fraction of the weight of noble metals, as well as plasmonic mode confinement and quality factors that are greater by an order of magnitude compared to noble metals. These findings hold promise for ultracompact optical components and wa...

Reworking processes and deposits in coral reefs during (very) high-energy events: Example from a Pleistocene coral formation (125 ka), La Désirade Island, Lesser Antilles

Abundant literature has documented the ecological impact of very high-energy (hurricane-type) events and high-energy (storm-type) events on modern coral reefs and sediment transport. In previous studies, sedimentary processes are often deduced from geophysical image analysis and scuba diving observations. Few field-based studies have been devoted to the impact of (very) high-energy disturbance on the structure and ecology of Holocene and Pleistocene coral reefs, and very few to the sedimentary processes acting around these reefs.This research examines the structure of the late Pleistocene (end of MIS5e stage) reefs of La Désirade Island, Guadeloupe Archipelago, Lesser Antilles, and focuses on the poorly known reworking processes and related coral-breccia sedimentation surrounding these reefs. Fieldwork was performed to document two coral-fragment-rich breccia interbedded with coral patches. The breccia predominantly show the same petrography but differ in their internal structure, showing a “massive breccia” type and a “stratified breccia” type. This work infers that these breccia are the result of gravity-induced high-density mass flows triggered by high to very-high energy events such as storms and hurricanes. Damage and reworking vary according to the type of (very) high-energy event. Prior to transport, storms are thought to have broken the heads of branching and columnar coral colonies, and broken and overturn isolated lamellar and massive colonies. Hurricanes (particularly their eye walls) may have reworked much more sediment than storms, and may have also destabilised entire several metre-sized columnar colonies from the flank of coral patch reefs. We propose the name “coral debrite” for these coral breccia deposits caused by gravity-induced debris flows.The reworked deposits are interbedded between two coral reef levels, of which the main coral-species vertical succession should record the end of Marine Isotope Stage 5e sea-level rise. Thus, reworking is believed to occur during the transitional stage between a glacial and an interglacial period.

Mechanistic Study of Copper-Catalyzed C-H Hydroxylation/C-S Coupling by ESI-HR MS and DFT Calculations.

The reaction mechanism of Cu-catalyzed C-H hydroxylation/C-S coupling was studied using electrospray ionization high resolution mass spectrometry (ESI-HR MS) and density functional theory calculations (DFT). Notably, a series of CuI and CuIII complexes were observed as key intermediates and identified using ESI-HR MS. Furthermore, a catalyst cycle involving proton abstraction/oxidative addition/reductive elimination was proposed. This study is important and valuable with respect to C-H functionalization.

Freestanding Cathode Electrode Design for High-Performance Sodium Dual-Ion Battery

In this work, both advantages of sodium-ion batteries and dual-ion batteries have been combined in an innovated sodium-ion-based dual-ion battery (SDI) system using a Na metal film as anode and a freestanding meso-carbon microbead film (FS-MCMB) as cathode. FS-MCMB in SDI battery exhibited a superior working performance with the specific capacity of 83.6 mAh/g and a remarkable long-term stability over 300 cycles. The SDI battery with FS-MCMB exhibited an advantage of high mass density loading in the range of 2–7.5 mg cm–2, which was equal to a comparable capacity of 78–83 mAh/g. The electrochemical impedance analysis indicated that FS-MCMB provided a superior permeability, resulting in facilitating electrolyte infiltration into MCMB structure. In-situ XRD and ex-situ Raman spectroscopy were utilized to characterize the intercalating/deintercalating process of PF6– anions into/out of MCMB during charging/discharging processes. Finally, theoretical calculations further confirmed the structural arrangement o...

Characterization of D-lactic acid, spore-forming bacteria and Terrilactibacillus laevilacticus SK5-6 as potential industrial strains

In this study, we screened and isolated D-lactic acid-producing bacteria from soil and tree barks collected in Thailand. Among the isolates obtained, Terrilactibacillus laevilacticus SK5-6 exhibited good D-lactate production in the primary screening fermentation (99.27 g/L final lactate titer with 0.90 g/g yield, 1.38 g/L⋅h, and 99.00% D-enantiomer equivalent). Terrilactibacillus laevilacticus SK5-6 is a Gram-positive, endospore-forming, homofermentative D-lactate producer that can ferment a wide range of sugars to produce D-lactate. Unlike the typical D-lactate producers, such as catalase-negative Sporolactobacillus sp., T. laevilacticus SK5-6 possesses catalase activity; therefore, a two-phase fermentation was employed for D-lactate production. During an aerobic preculture stage, a high-density cell mass was rapidly obtained due to aerobic respiration. When transferred to the fermentation stage at the correct physiological stage (inoculum age) and proper concentration of cell mass (inoculum size), T. laevilacticus rapidly converted glucose into D-lactate under anaerobic conditions, resulting in a high final lactate titer (102.22 g/L), high yield (0.84 g/g), and high productivity (2.13 g/L⋅h). When the process conditions were shifted from an aerobic to an anaerobic environment, unlike other lactate-producing bacteria, the mixed acid fermentation route was not activated in the culture of T. laevilacticus SK5-6 during the fermentation stage when some trace oxygen still remained. Our study demonstrates the excellent characteristics of this isolate for D-lactate production; in particular, a high product yield was obtained without byproduct formation. Based on these key characteristics of T. laevilacticus SK5-6, we suggest that this isolate is a novel D-lactate producer for use in industrial fermentation.

Enceladus plume density from Cassini spacecraft attitude control data

The plumes of Enceladus are of interest both as a geophysical phenomenon, and as an astrobiological opportunity for sampling internal material. Here we report measurements of the total mass density (gas plus dust, a combination not reported before except in the engineering literature) deduced from telemetry of Cassini's Attitude and Articulation Control System (AACS), as the spacecraft's thrusters or reaction wheels worked to maintain the desired attitude in the presence of drag torques during close flybys. The drag torque shows good agreement with the water vapor density measured by other instruments during the E5 encounter, but indicates a rather higher mass density on other passes (E3, E14), possibly indicating variations in gas composition and/or gas:dust ratio. The spacecraft appears to have intercepted about 0.2 g of material, on flyby E21 in October 2015 indicating a peak mass density of ∼5.5 × 10−11 kg m−3, the highest of all the flybys measured (E3, E5, E7, E9, E14, E21).

A rare-earth free magnesium alloy with improved intrinsic ductility

Metals are the backbone of manufacturing owing to their strength and formability. Compared to polymers they have high mass density. There is, however, one exception: magnesium. It has a density of only 1.7 g/cm3, making it the lightest structural material, 4.5 times lighter than steels, 1.7 times lighter than aluminum, and even slightly lighter than carbon fibers. Yet, the widespread use of magnesium is hampered by its intrinsic brittleness. While other metallic alloys have multiple dislocation slip systems, enabling their well-known ductility, the hexagonal lattice of magnesium offers insufficient modes of deformation, rendering it intrinsically brittle. We have developed a quantum-mechanically derived treasure map which screens solid solution combinations with electronic bonding, structure and volume descriptors for similarity to the ductile magnesium-rare earth alloys. Using this insight we synthesized a surprisingly simple, compositionally lean, low-cost and industry-compatible new alloy which is over 4 times more ductile and 40% stronger than pure magnesium. The alloy contains 1 wt.% aluminum and 0.1 wt.% calcium, two inexpensive elements which are compatible with downstream recycling constraints.

The SAMI Galaxy Survey: global stellar populations on the size–mass plane

We present an analysis of the global stellar populations of galaxies in the SAMI Galaxy Survey. Our sample consists of 1319 galaxies spanning four orders of magnitude in stellar mass and includes all morphologies and environments. We derive luminosity-weighted, single stellar population equivalent stellar ages, metallicities and alpha enhancements from spectra integrated within one effective radius apertures. Variations in galaxy size explain the majority of the scatter in the age--mass and metallicity--mass relations. Stellar populations vary systematically in the plane of galaxy size and stellar mass, such that galaxies with high stellar surface mass density are older, more metal-rich and alpha-enhanced than less dense galaxies. Galaxies with high surface mass densities have a very narrow range of metallicities, however, at fixed mass, the spread in metallicity increases substantially with increasing galaxy size (decreasing density). We identify residual correlations with morphology and environment. At fixed mass and size, galaxies with late-type morphologies, small bulges and low Sersic n are younger than early-type, high n, high bulge-to-total galaxies. Age and metallicity both show small residual correlations with environment; at fixed mass and size, galaxies in denser environments or more massive halos are older and somewhat more metal rich than those in less dense environments. We connect these trends to evolutionary tracks within the size--mass plane.

Comparison of Metabolic Syndrome Indicators in Two Samples of Central and South Americans Living in the Washington, D.C. Area in 1993-1994 and 2008-2009: Secular Changes in Metabolic Syndrome in Hispanics.

The Central and South American populations are growing rapidly in the US; however, there is a paucity of information about their health status. Objectives: we estimated the prevalence of metabolic syndrome (MetS) and its individual components from two cohorts of Central and South Americans. Methods: This cross-sectional, medical record extraction survey sampled 1641 adults from a Washington, D.C clinic. A questionnaire was used to collect socio-demographic, medical history, anthropometric, biochemical, and clinical data. Results: among the 1993–1994 cohort, the MetS prevalence was 19.7%. The most prevalent MetS components were low high-density lipoprotein (HDL) cholesterol (40.4% men and 51.3% women), elevated triglycerides (40.9% men and 33.1% women), and high body mass index (BMI) ≥ 25 kg/m2 (27.6% men and 36.6% women). The overall prevalence of MetS in the 2008–2009 cohort was 28%. The most common abnormal metabolic indicator was an elevated BMI ≥ 25 kg/m2 (75.6%). 43.2% of men and 50.7% of women had HDL levels below normal, while the prevalence of hypertriglyceridemia was 46.5% and 32.5% for men and women, respectively. Conclusion: the prevalence of MetS was significantly greater in 2008–2009 compared with 1993–1994 (p ≤ 0.05). Dyslipidemia and high BMI have increased. Although similar components were identified in both the 1993–1994 and 2008–2009 study populations, the risks of MetS have increased over time.

Ion induced stress relaxation in dense sputter-deposited DLC thin films

Deposition of high-density and low-stress hydrogen-free diamond like carbon (DLC) thin films is demonstrated using a pulsed ionized sputtering process. This process is based on high power impulse magnetron sputtering, and high C ionization is achieved using Ne as the sputtering gas. The intrinsic compressive stress and its evolution with respect to ion energy and ion flux are explained in terms of the compressive stress based subplantation model for DLC growth by Davis. The highest mass density was ∼2.7 g/cm3, and the compressive stresses did not exceed ∼2.5 GPa. The resulting film stresses are substantially lower than those achieved for the films exhibiting similar mass densities grown by filtered cathodic vacuum arc and pulsed laser deposition methods. This unique combination of high mass density and low compressive stress is attributed to the ion induced stress relaxation during the pulse-off time which corresponds to the post thermal spike relaxation timescales. We therefore propose that the temporal ion flux variations determine the magnitude of the compressive stress observed in our films.

Self-Powered Acceleration Sensor Based on Liquid Metal Triboelectric Nanogenerator for Vibration Monitoring.

An acceleration sensor is an essential component of the vibration measurement, while the passivity and sensitivity are the pivotal features for its application. Here, we report a self-powered and highly sensitive acceleration sensor based on a triboelectric nanogenerator composed of a liquid metal mercury droplet (LMMD) and nanofiber-networked polyvinylidene fluoride (nn-PVDF) film. Due to the ultrahigh surface-to-volume ratio of nn-PVDF film and high surface tension, high mass density, high elastic as well as mechanical robustness of LMMD, the open-circuit voltage and short-circuit current reach up to 15.5 V and 300 nA at the acceleration of 60 m/s2, respectively. The acceleration sensor has a wide detection range from 0 to 60 m/s2 with a high sensitivity of 0.26 V·s/m2. Also, the output voltage and current show a negligible decrease over 200,000 cycles, evidently presenting excellent stability. Moreover, a high-speed camera was employed to dynamically capture the motion state of the acceleration sensor for insight into the corresponding work mechanism. Finally, the acceleration sensor was demonstrated to measure the vibration of mechanical equipment and human motion in real time, which has potential applications in equipment vibration monitoring and troubleshooting.

Intranasal eosinophilic angiocentric fibrosis associated with an IgG4-related disease

Abstract Eosinophilic angiocentric fibrosis is an uncommon tumefactive lesion of the ocular orbit and upper respiratory tract. We present a 44-year old man with a history of severe nasal congestion and nasal obstruction. The patient also reported symptoms of sinusitis. Submucous thickening tissue had been locally resected and the involved anterior nasal septum cartilage partially removed. Histopathological examination of the biopsy indicated eosinophilic angiocentric fibrosis. A CT scan of the sinuses showed a high-density focal mass of soft tissue arising from the anterior aspect of the nasal septum. Examination under low power view showed dense concentric fibrosis and mixed inflammatory cells. The fibrosis was in an angiocentric pattern, resembling an onionskin. High power view showed a mixture of lymphocytes, plasma cells, numerous eosinophils, and proliferating fibroblasts. A test for serum IgG performed ten years after the patient's initial presentation was 1421 mg/dl (normal range 540–1822 mg/dl), and the serum concentration of IgG4 was 168.70 mg/dl (normal range 6.1–121 mg/dl). A review of the original hematoxylin and eosin-stained slides revealed that this case was stained immunohistochemically with an IgG4 stain showing 50 IgG4-positive plasma cells/HPF.

The Universe, a Personal View on Exploring the Boundaries, or: The Science of the Extremes

What are the fundamental equations of motion when we consider objects that move faster, have tinier structures, higher mass densities, higher or lower temperatures than ever studied before? Here, we emphasize the importance of studying extreme conditions and situations in science so as to uncover the basic laws of nature. One of the important extremes is extreme complexity, a necessary condition for the emergence of life.

Correlation between calculated molecular descriptors of excipient amino acids and experimentally observed thermal stability of lysozyme

A quantitative structure-property relationship (QSPR) between protein stability and the physicochemical properties of excipients was investigated to enable a more rational choice of stabilizing excipients than prior knowledge. The thermal transition temperature and aggregation time were determined for lysozyme in combination with 13 different amino acids using high throughput fluorescence spectroscopy and kinetic static light scattering measurements. On the theoretical side, around 200 2D and 3D molecular descriptors were calculated based on the amino acids’ chemical structure. Multivariate data analysis was applied to correlate the descriptors with the experimental results. It was possible to identify descriptors, i.e. amino acids properties, with a positive influence on either transition temperature or aggregation onset time, or both. A high number of hydrogen bond acceptor moieties was the most prominent stabilizing factor for both responses, whereas hydrophilic surface properties and high molecular mass density mostly had a positive influence on the unfolding temperature. A high partition coefficient (logP(o/w)) was identified as the most prominent destabilizing factor for both responses. The QSPR shows good correlation between calculated molecular descriptors and the measured stabilizing effect of amino acids on lysozyme.

Cross-linked poly(acrylic acid)-carboxymethyl cellulose and styrene-butadiene rubber as an efficient binder system and its physicochemical effects on a high energy density graphite anode for Li-ion batteries

An increase in graphite anode thickness is an effective way to achieve a high-energy density lithium ion battery by designing a compact cell with a high mass loading and density. However, this may cause critical problems in Li+ diffusivity due to drastic increases in length and tortuosity of the ionic migration path. A mixture of cross-linked poly (acrylic acid) (PAA)–carboxymethyl cellulose hydrogels (CMC) was developed using styrene-butadiene rubber (SBR) as an efficient binder system to increase Li+ diffusivity and adhesion strength. Electrolyte permeability and adhesion strength of the electrode were enhanced by 2.5 and 2 times, respectively, compared to a conventional CMC–SBR system, which led to excellent electrochemical properties due to enhanced affinity with electrolytic and interpolymeric properties. Particularly, capacity retention was improved from 81 to 91% at a high 1C rate.