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Yazan Fahmawi,1 Yesica Campos,1 Moh’d Khushman,2 Omar Alkharabsheh,2 Ashish Manne,2 Haseeb Zubair,2 Saadia Haleema,3 Jacek Polski,3 Sabrina Bessette11Department of Internal Medicine, University of South Alabama, Mobile, AL, USA; 2Department of Hematology-Oncology, Mitchell Cancer Institute, University of South Alabama, Mobile, AL, USA; 3Department of Pathology, University of South Alabama, Mobile, AL, USACorrespondence: Yazan FahmawiDepartment of Internal Medicine, University of South Alabama, 2451 USA Medical Center Drive, Mobile, AL 36617, USATel +1 251 471 7891Fax +1 251 470 1652Email yfahmawi@health.southalabama.eduAbstract: Pseudo-thrombotic microangiopathy (pseudo-TMA) is a recognized, yet uncommon, clinical presentation of vitamin B12 deficiency. Patients with pseudo-TMA present with microangiopathic hemolytic anemia (MAHA), thrombocytopenia and schistocytes. They are often misdiagnosed as thrombotic thrombocytopenia purpura (TTP) and receive unnecessary therapy. Here, we report a case of a 60-year-old male who presented with thrombocytopenia and normocytic normochromic anemia. Anemia work-up was remarkable for severe B12 deficiency (

Electron beam damage in electron microscopes is becoming more and more problematic in material research with the increasing demand of characterization of new beam sensitive material such as Li based compounds used in lithium-ion batteries. To avoid radiolysis damage, it has become common practice to use Cryo-EM, however, knock-on damage can still occur in conventional TEM/STEM with a high-accelerating voltage (200-300 keV). In this work, electron energy loss spectroscopy with an accelerating voltage of 30,20 and 10 keV was explored with h-BN, TiB 2 and TiN compounds. All Ti L 2,3, N K and B K edges were successfully observed with an accelerating voltage as low as 10 keV. An accurate elemental quantification for all three samples was obtained using a multi-linear least square (MLLS) procedure which gives at most a 5 % of standard deviation which is well within the error of the computation of the inelastic partial-cross section used for the quantification. These results show the great potential of using low-voltage EELS which is another step towards a knock-on damage free analysis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Raynald Gauvin reports financial support was provided by Natural Sciences and Engineering Research Council of Canada. Raynald Gauvin reports financial support was provided by Hydro-Québec. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

In this work, the configuration of compact TiO 2 coating (c-TiO 2 ) interface as electron transport layer (ETL) in giving rise to loss and gain of fill factor (FF) and therefore modulation of hysteresis behavior in perovskite solar cells (PSCs) is investigated. For this purpose, PSCs based on planar compact TiO 2 (c-TiO 2 ) as well as a scaffold-based architecture are studied. In the latter case c-TiO 2 coats a hydrothermally grown titania nanorod scaffold. The results demonstrate that when c-TiO 2 is used in planar configuration, FF considerably improves with prolonged light soaking which is in sharp contrast to what is observed for scaffold-based PSCs. Moreover, higher thickness of planar c-TiO 2 is shown to be beneficial for sustaining FF in forward scan. Finally, through studying the intricate interfacial dynamics utilizing electrochemical impedance spectroscopy (EIS), it was concluded that for a PSC under operation, the cumulative effect of conductivity modulation at the perovskite with transport layer interfaces, for their respective charge carriers, determines the loss and gain in performance depending on scan rate, applied bias and prolonged light soaking. This work points towards multiple factors affecting PSC output, which could work either in confluence or against one another depending on the interfacial configuration of transport layers.

The jellyfish Cassiopea largely cover their carbon demand via photosynthates produced by microalgal endosymbionts, but how holobiont morphology and tissue optical properties affect the light microclimate and symbiont photosynthesis in Cassiopea remain unexplored. Here, we use optical coherence tomography (OCT) to study the morphology of Cassiopea medusae at high spatial resolution. We include detailed 3D reconstructions of external micromorphology, and show the spatial distribution of endosymbionts and white granules in the bell tissue. Furthermore, we use OCT data to extract inherent optical properties from light-scattering white granules in Cassiopea, and show that granules enhance local light-availability for symbionts in close proximity. Individual granules had a scattering coefficient of µ s = 200-300 cm -1 , and scattering anisotropy factor of g = 0.7, while large tissue-regions filled with white granules had a lower µ s = 40-100 cm -1 , and g = 0.8-0.9. We combined OCT information with isotopic labelling experiments to investigate the effect of enhanced light-availability in whitish tissue regions. Endosymbionts located in whitish tissue exhibited significantly higher carbon fixation compared to symbionts in anastomosing tissue (i.e. tissue without light-scattering white granules). Our findings support previous suggestions that white granules in Cassiopea play an important role in the host modulation of the light-microenvironment.

In this study, to elucidate the origin of inductance and its relationship with the phenomenon of hysteresis in hybrid perovskite solar cells (PSCs), two electron transport layer (ETL) structures have been utilized: (a) rutile titania nanorods grown over anatase titania (AR) and (b) anatase titania covering the rutile titania nanorods (RA). The rutile and anatase phases are prepared via hydrothermal synthesis and spray pyrolysis, respectively. PSCs based on an ETL with an RA structure attain higher short-circuit current density ( J SC ) and open-circuit voltage ( V OC ) while showing a slightly lower fill factor (FF) compared with their AR counterparts. Using electrochemical impedance spectroscopy (EIS) measurements, we show that the ETL plays a major role in setting the tone for ionic migration speed and consequent accumulation. Moreover, we consider the conductivity of transport layers as a determining factor in not only giving rise to inductive features but also dictating the bias region under which recombination takes place, ultimately influencing hysteresis locus.

The upside-down jellyfish Cassiopea engages in symbiosis with photosynthetic microalgae that facilitate uptake and recycling of inorganic nutrients. By contrast to most other symbiotic cnidarians, algal endosymbionts in Cassiopea are not restricted to the gastroderm but are found in amoebocyte cells within the mesoglea. While symbiont-bearing amoebocytes are highly abundant, their role in nutrient uptake and cycling in Cassiopea remains unknown. By combining isotopic labelling experiments with correlated scanning electron microscopy, and Nano-scale secondary ion mass spectrometry (NanoSIMS) imaging, we quantified the anabolic assimilation of inorganic carbon and nitrogen at the subcellular level in juvenile Cassiopea medusae bell tissue. Amoebocytes were clustered near the sub-umbrella epidermis and facilitated efficient assimilation of inorganic nutrients. Photosynthetically fixed carbon was efficiently translocated between endosymbionts, amoebocytes and host epidermis at rates similar to or exceeding those observed in corals. The Cassiopea holobionts efficiently assimilated ammonium, while no nitrate assimilation was detected, possibly reflecting adaptation to highly dynamic environmental conditions of their natural habitat. The motile amoebocytes allow Cassiopea medusae to distribute their endosymbiont population to optimize access to light and nutrients, and transport nutrition between tissue areas. Amoebocytes thus play a vital role for the assimilation and translocation of nutrients in Cassiopea , providing an interesting new model for studies of metabolic interactions in photosymbiotic marine organisms.

A technique to characterize the native passivation layer (NPL) on pure lithium metal foils in a scanning electron microscope (SEM) is described in this paper. Lithium is a very reactive metal, and consequently, observing and quantifying its properties in a SEM is often compromised by rapid oxidation. In this work, a pure lithium energy-dispersive x-ray spectrum is obtained for the first time in a high vacuum SEM using a cold stage/cold trap with liquid nitrogen reservoir outside the SEM chamber. A nanomanipulator (OmniProbe 400) inside the microscope combined with x-ray microanalysis and windowless energy dispersive spectrometer is used to fully characterize the NPL of lithium metal and some of its alloys by a mechanical removal procedure. The results show that the native films of pure lithium and its alloys are composed of a thin (25 nm) outer layer that is carbon-rich and an inner layer containing a significant amount of oxygen. Differences in thickness between laminated and extruded samples are observed and vary depending on the alloy composition.

Organic cathode materials for lithium batteries are becoming increasingly popular because they have high theoretical redox voltage, high gravimetric capacity, low cost, easy processing and sustainability. However, their development is limited by their solubility in the electrolyte, which leads to rapid deterioration of the battery upon cycling. We developed a Janus membrane, which consists of two layers - a commercial polypropylene separator (Celgard) and a 300-600 nm layer of exfoliated graphite that was applied by a simple and environmentally friendly process. The submicron graphite layer is only permeable to Li + and it drastically improves the battery performance, as measured by capacity retention and high coulombic efficiency, even at 2C rates. Post-mortem analysis of the battery indicates that the new membrane protects the anode against corrosion, and cathode dissolution is reduced. This graphite-based membrane is expected to greatly expedite the deployment of batteries with organic cathodes.

Li metal batteries suffer from dendrite formation which causes short circuit of the battery. Therefore, it is important to understand the chemical composition and growth mechanism of dendrites that limit battery efficiency and cycle life. In this study, in situ scanning electron microscopy was employed to monitor the cycling behavior of all-solid Li metal batteries with LiFePO 4 cathodes. Chemical analyses of the dendrites were conducted using a windowless energy dispersive spectroscopy detector, which showed that the dendrites are not metallic lithium as universally recognized. Our results revealed the carbide nature of the dendrites with a hollow morphology and hardness greater than that of pure lithium. These carbide-based dendrites were able to perforate through the polymer, which was confirmed by milling the polymer using focused ion beam. It was also shown that applying pressure on the battery can suppress growth of the dendrites.

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) using a focused ion-beam scanning electron microscope (FIB-SEM) is a promising and economical technique for lithium detection and quantification in battery materials because it overcomes the limitations with detecting low Li content by energy dispersive spectroscopy (EDS). In this work, an experimental calibration curve was produced, which to our best knowledge allowed for the first time, the quantification of lithium in standard nickel manganese cobalt oxide (NMC-532) cathodes using 20 nm resolution. The technique overcomes matrix effects and edges effects that makes quantification complex. This work shows the high potential of TOF-SIMS tool for analytical characterization of battery materials, and demonstrates its tremendous capabilities towards identification of various chemical or electrochemical phenomena in the cathodes via high-resolution ion distributions. Various phenomena in the ion distributions are also assessed, such as edge effects or measurement artifacts from real signal variations.

Sitting at ∼5,000 m water depth on the Congo-Angola margin and ∼760 km offshore of the West African coast, the recent lobe complex of the Congo deep-sea fan receives large amounts of fluvial sediments (3-5% organic carbon). This organic-rich sedimentation area harbors habitats with chemosynthetic communities similar to those of cold seeps. In this study, we investigated relative abundance, diversity and distribution of aerobic methane-oxidizing bacteria (MOB) communities at the oxic-anoxic interface of sedimentary habitats by using fluorescence in situ hybridization and comparative sequence analysis of particulate mono-oxygenase ( pmoA ) genes. Our findings revealed that sedimentary habitats of the recent lobe complex hosted type I and type II MOB cells and comparisons of pmoA community compositions showed variations among the different organic-rich habitats. Furthermore, the pmoA lineages were taxonomically more diverse compared to methane seep environments and were related to those found at cold seeps. Surprisingly, MOB phylogenetic lineages typical of terrestrial environments were observed at such water depth. In contrast, MOB cells or pmoA sequences were not detected at the previous lobe complex that is disconnected from the Congo River inputs.

Aedes aegypti and Anopheles gambiae are two mosquito species that represent significant threats to global public health as vectors of Dengue virus and malaria parasites, respectively. Although mosquito populations have been effectively controlled through the use of synthetic insecticides, the emergence of widespread insecticide-resistance in wild mosquito populations is a strong motivation to explore new insecticidal chemistries. For these studies, Ae. aegypti and An. gambiae were treated with commercially available plant essential oils via topical application. The relative toxicity of each essential oil was determined, as measured by the 24-h LD(50) and percentage knockdown at 1 h, as compared with a variety of synthetic pyrethroids. For Ae. aegypti, the most toxic essential oil (patchouli oil) was ∼1,700-times less toxic than the least toxic synthetic pyrethroid, bifenthrin. For An. gambiae, the most toxic essential oil (patchouli oil) was ∼685-times less toxic than the least toxic synthetic pyrethroid. A wide variety of toxicities were observed among the essential oils screened. Also, plant essential oils were analyzed via gas chromatography/mass spectrometry (GC/MS) to identify the major components in each of the samples screened in this study. While the toxicities of these plant essential oils were demonstrated to be lower than those of the synthetic pyrethroids tested, the large amount of GC/MS data and bioactivity data for each essential oil presented in this study will serve as a valuable resource for future studies exploring the insecticidal quality of plant essential oils., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

This study compared the mechanical and biomechanical functions, metabolic demand, and shock absorption of two dynamic elastic response (DER) prosthetic foot designs with the SACH foot. Nine individuals who had undergone unilateral below knee amputation were studied. Mechanical properties of the feet were related to gait biomechanics. Forefoot compliance is greatest for the Flex Foot and least for the SACH foot, hence, Flex Foot demonstrates (1) the longest midstance phase, (2) the greatest ankle angle range, and (3) greater forward movement of the center of pressure. There was some evidence that the DER feet produced a better push-off. However, neither the self-selected walking speed nor the metabolic rate or efficiency over a spectrum of walking speeds (73 to 120m/min) and running speeds (140 to 200m/min) was significantly different. Because no energy savings resulted for the DER feet, the release of stored energy in the flexible feet may not occur at the proper time to assist in ambulation as a result of the natural frequency of oscillation.

This study evaluated biomechanical and metabolic performance differences between two prosthetic foot designs in light of their mechanical properties. Ten unilateral below-knee amputee subjects, at least 1 year after amputation, capable of walking and running, were studied. Differences in heel and forefoot compliance explained differences in gait events and alignment. Increased efficiency of pushoff in the Seattle Ankle/Lite Foot exists as evidenced by the decrease loading on the opposite limb during double support and a less shortened step length on the sound side compared to the SACH foot. The natural frequency of oscillation for the prosthetic feet was determined to be too high to provide energy storage and release synchronized with kinematic requirements because neither metabolic cost savings nor differences in metabolic efficiency were found. Comfortable walking speed and the nadir of metabolic rate and efficiency are not different. Via accelerometer measurement, it was found that the more compliant and lossy SACH foot heel was less likely to transmit high frequency vibration.

The application of cryotherapy to temporarily reduce spasticity is a widespread clinical practice. A method of quantifying spasticity, based on viscoelastic stiffness measurements at the ankle, was applied to objectively determine the efficacy of cryotherapy in reducing spasticity of the calf. Baseline, cryotherapy and one-hour postcryotherapy measurements of spasticity were performed in 25 subjects with clinical signs of spasticity secondary to traumatic brain injury, spinal cord injury, and stroke. A statistically significant reduction in spasticity occurred during cryotherapy. Postcryotherapy results were equivocal, although there was a tendency for diminished spasticity relative to the baseline measurement. Two subjects showed a clear aggravation of spasticity following cryotherapy, thus leading to the conclusion that dichotomous results are possible.