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A full understanding of the sequence of processes exhibited by yield stress fluids under large amplitude oscillatory shearing is developed using multiple experimental and analytical approaches. A novel component rate Lissajous curve, where the rates at which strain is acquired unrecoverably and recoverably are plotted against each other, is introduced and its utility is demonstrated by application to the analytical responses of four simple viscoelastic models. Using the component rate space, yielding and unyielding are identified by changes in the way strain is acquired, from recoverably to unrecoverably and back again. The behaviors are investigated by comparing the experimental results with predictions from the elastic Bingham model that is constructed using the Oldroyd–Prager formalism and the recently proposed continuous model by Kamani, Donley, and Rogers in which yielding is enhanced by rapid acquisition of elastic strain. The physical interpretation gained from the transient large amplitude oscillatory shear (LAOS) data is compared to the results from the analytical sequence of physical processes framework and a novel time-resolved Pipkin space. The component rate figures, therefore, provide an independent test of the interpretations of the sequence of physical processes analysis that can also be applied to other LAOS analysis frameworks. Each of these methods, the component rates, the sequence of physical processes analysis, and the time-resolved Pipkin diagrams, unambigiously identifies the same material physics, showing that yield stress fluids go through a sequence of physical processes that includes elastic deformation, gradual yielding, plastic flow, and gradual unyielding.

Shear banding in entangled polymer solutions is an elusive phenomenon in polymer rheology. One recently proposed mechanism for the existence of banded velocity profiles in entangled polymer solutions stems from a coupling of the flow to banded concentration profiles. Recent work [Burroughs et al., Phys. Rev. Lett . 126, 207801 (2021)] provided experimental evidence for the development of large gradients in concentration across the fluid. Here, a more systematic investigation is reported of the transient and steady-state banded velocity and concentration profiles of entangled polybutadiene in dioctyl phthalate solutions as a function of temperature [Formula: see text], number of entanglements ([Formula: see text]), and applied shear rate ([Formula: see text]), which control the susceptibility of the fluid to unstable flow-concentration coupling. The results are compared to a two-fluid model that accounts for coupling between elastic and osmotic polymer stresses, and a strong agreement is found between model predictions and measured concentration profiles. The interface locations and widths of the time-averaged, steady-state velocity profiles are quantified from high-order numerical derivatives of the data. At high levels of entanglement and large [Formula: see text], a significant wall slip is observed at both inner and outer surfaces of the flow geometry but is not a necessary criterion for a nonhomogeneous flow. Furthermore, the transient evolution of flow profiles for large Z indicate transitions from curved to “stair-stepped” and, ultimately, a banded steady state. These observed transitions provide detailed evidence for shear-induced demixing as a mechanism of shear banding in polymer solutions.

A thorough study is made of the dependences on salt concentration and polymer chain lengths of the low-frequency plateau of coacervates of poly (diallyl dimethyl ammonium chloride), PDADMAC, and poly (sodium 4-styrenesulfonate), PSS. The reliability and reproducibility of these measurements are carefully checked by determining the frequency-dependent stress limits of the rheometer through the use of reference fluids and by repeat experiments with coacervates. Long-time frequency sweeps show that coacervates with less salt are more repeatable than those with higher salt. A low-frequency plateau reliably appears only below a critical salt concentration, and the magnitude of the plateau depends strongly on salt concentration and chain lengths of both polycation and polyanion. It is only present for the molecular weight of the polycation, PDADMAC, higher than 100 kDa, but the magnitude of the plateau is more strongly influenced by the chain length of the polyanion, PSS. Possible causes of the low-frequency plateau are discussed.

Introduction: we briey describe the purpose and indications of colostomy Cases And Discussion: we have studied six prototypical cases of postoperative stoma complications and have discussed them in light of their management. Conclusion: we highlight the importance of adequate stoma creation and care

Emerging 3D printing technologies offer an exciting opportunity to create customized 3D objects additively from a digital design file. 3D printing may be further leveraged for personalized medicine, clinical trial, and controlled release applications. A wide variety of 3D printing methods exists, and many studies focus on extrusion-based 3D printing techniques that closely resemble hot melt extrusion. In this paper, we explore different pharmaceutical-grade feedstock materials for creating tablet-like dosage forms using a binder jet 3D printing method. In this method, pharmaceutical-grade powders are repeatedly spread onto a build plate, followed by inkjet printing a liquid binder to selectively bind the powders in a predetermined pattern. The physical properties of the pharmaceutical-grade powders and binders have been characterized and a molding method has been developed to select appropriate powder and binder materials for subsequent printing experiments. There was a correlation between the breaking forces of the molded and printed samples, but no clear correlation was observed for disintegration time, which was primarily controlled by the higher porosity of the printed samples. The breaking force and disintegration properties of as-printed and post-processed samples containing indomethacin as an active pharmaceutical ingredient have been measured and compared with relevant literature data.

Materials that exhibit yielding behavior are used in many applications, from spreadable foods and cosmetics to direct write three-dimensional printing inks and filled rubbers. Their key design feature is the ability to transition behaviorally from solid to fluid under sufficient load or deformation. Despite its widespread applications, little is known about the dynamics of yielding in real processes, as the nonequilibrium nature of the transition impedes understanding. We demonstrate an iteratively punctuated rheological protocol that combines strain-controlled oscillatory shear with stress-controlled recovery tests. This technique provides an experimental decomposition of recoverable and unrecoverable strains, allowing for solid-like and fluid-like contributions to a yield stress material's behavior to be separated in a time-resolved manner. Using this protocol, we investigate the overshoot in loss modulus seen in materials that yield. We show that this phenomenon is caused by the transition from primarily solid-like, viscoelastic dissipation in the linear regime to primarily fluid-like, plastic flow at larger amplitudes. We compare and contrast this with a viscoelastic liquid with no yielding behavior, where the contribution to energy dissipation from viscous flow dominates over the entire range of amplitudes tested.

The direct measurement of cohesion under high strain and the quantitative effects of solid matrix structure on particle morphology and bulk rheology have not been explored thoroughly in literature. A Warren Springs geometry installed on an air bearing rotational rheometer capable of capturing the amount of shear stress required for powder failure at a wide range of initial consolidation states was implemented in the study to measure the cohesion trend of over-consolidated powder materials. Wheat, potato, corn starches and microcrystalline cellulose (MCC PH101) powders were analyzed. MCC PH101 powder exhibited the highest weighted cohesion strength among the powders at all consolidation stresses because of the high particle aspect ratio given the inherited crystallinity of its compositional matrix. MCC sample also had greater variation between incipient and steady state portions of the torque profile attributable to its characteristic particle stiffness, which, consequently, yielded in distinct particle deformation behavior.

Consistency and reliable flow are of great concern during the handling and processing of flour. In this study, wheat flour was consolidated by normal stress and vibration, and rheological factors including bulk solid compressibility, Warren-Spring cohesion strength, permeability, and wall friction were evaluated. Soft red winter (SRW) and hard red spring (HRS) wheat flours were vibrated for 5 and 10 minutes and compressed under 10 and 20 kPa for 12 and 24 h. After vibration, wall friction increased from 10.87° to 14.13° for SRW flour and decreased from 11.00° to 7.10° for HRS flour, and the permeability decreased for both the flours. Consolidation time and stress had a significant effect (P < 0.05) on wall friction and compressibility. The HRS Carr index increased from 25.77 to 38.48 when consolidated under 20 kPa for 24 hours, but the SRW Carr index decreased slightly from 46.60 to 44.24. The SRW flour permeability decreased significantly (P < 0.05) when compression pressure was increased from 10 to 20 kPa. while HRS permeability was less affected by consolidation. The consolidation and vibration effects on bulk flour properties differed likely due to inherent differences in the composition and hardness of HRS and SRW.

We develop a novel connection between discrepancy minimization and (quantum) communication complexity. As an application, we resolve a substantial special case of the Matrix Spencer conjecture. In particular, we show that for every collection of symmetric $n \times n$ matrices $A_1,\ldots,A_n$ with $\|A_i\| \leq 1$ and $\|A_i\|_F \leq n^{1/4}$ there exist signs $x \in \{ \pm 1\}^n$ such that the maximum eigenvalue of $\sum_{i \leq n} x_i A_i$ is at most $O(\sqrt n)$. We give a polynomial-time algorithm based on partial coloring and semidefinite programming to find such $x$. Our techniques open a new avenue to use tools from communication complexity and information theory to study discrepancy. The proof of our main result combines a simple compression scheme for transcripts of repeated (quantum) communication protocols with quantum state purification, the Holevo bound from quantum information, and tools from sketching and dimensionality reduction. Our approach also offers a promising avenue to resolve the Matrix Spencer conjecture completely -- we show it is implied by a natural conjecture in quantum communication complexity.

Recent research on tumorigenesis and progression has opened up an array of novel molecular mechanisms in the form of interactions between cellular non-coding RNAs (long non-coding RNA[lncRNA]/microRNA [miRNA]) and coding transcripts that regulate health and disease. Endometrial cancer (EC) is a prominent gynecological malignancy with a high incidence rate and poorly known etiology and prognostic factors that hinder the success of disease management. The emerging role of lncRNA-miRNA-mRNA interactions and their dysregulation in the pathophysiology of EC has been elucidated in many recent studies.A thorough literature review was conducted to explore information about lncRNA-miRNA-mRNA axes in EC.Several lncRNAs act as molecular sponges that sequester various tumor suppressor miRNAs to inhibit their function, leading to the dysregulation of their target mRNA transcripts that contribute to the EC regulation.This review summarizes these networks of molecular mechanisms and their contribution to different aspects of endometrial carcinogenesis, leading to a better conceptualization of the molecular pathways that underlie the disease and helping establish novel diagnostic biomarkers and therapeutic intervention points to aid the curative intent of EC.

Dynamic Mechanical Analysis (DMA) is conducted to measure the viscoelastic nature of a material. The commercial DMA equipment calculates the complex modulus ( E*) by assuming a constant Poisson’s ratio. In this work, a method is developed for the simultaneous measurement of Poisson’s ratio and complex modulus ( E*) for carbon fiber (CF) reinforced Acrylonitrile Butadiene Styrene (ABS) composites using in-situ optical measurements and digital image correlation. The computation of E* includes shear deflection and relaxes the assumption of constant Poisson’s ratio to obtain accurate values. DMA was conducted on 3D printed CF-ABS composite specimens with oscillating displacement of 10 µm and static load of 1 N at 1 Hz loading frequency. The results in this work reveal that CF-ABS composite does not have a constant Poisson’s ratio over temperature. Additionally, applying the Poisson’s ratio correction results in higher values for the complex modulus. This work is beneficial for composites where the shear deflection component should not be neglected, and where variation of Poisson’s ratio with respect to temperature is important.

Introduction: MRSA peritonitis is documented in literature as being secondary to peritoneal dialysis but it is a lesser known cause of perforation peritonitis Case presentation: we report a 72 year old male with rectosigmoid cancer perforation with MRSA peritonitis and his emergency surgical management Conclusion: we conclude that though MRSA peritonitis in this patient followed a fulminant course which was exacerbated by his underlying disease process.

Introduction:Colonic Atresia is the least common type of Intestinal Atresia which occurs as a result of ischemic necrosis of a segment of large intestine.It presents with abdominal distention,bilious vomiting and failure to pass meconium.Perforation leads to peritonitis and sepsis Case Report:We describe a 3 day old male baby presenting with Colonic Atresia type IIIa and pneumoperitoneum and his surgical management Conclusion:In conclusion, Colonic Atresia is managed by either by colostomy or primary anastomosis.Terminal ileostomy,as in this case is done when there is Ascending Colon atresia with distal ileal perforation.

INTRODUCTION: Brain herniations have been labelled as 'Brain Code' to signify the emergent need for diagnosis and intervention. Traumatic Brain Injury is the most common cause of brain herniation which could be lateral, subfalcine, descending transtentorial, tonsillar, upward or transcalvarial. CASE: Three cases of descending transtentorial herniation,their imaginary and their operative intervention are discussed. DISCUSSION: The clinical features and the previous works on descending transtentorial herniation are discussed in brief. CONCLUSION: In conclusion, the three cases discussed had a rapid resolution of symptoms after surgical intervention.

Systemic Lupus Erythematosis (SLE) is a chronic autoimmune disease of unknown cause that can affect virtually any organ of the body. Anti dsDNA antibody has been considered as a marker of renal disease. Hence elevated levels are expected in patients with Lupus Nephritis (LN). But in a subset of these patients anti dsDNA antibody is negative and this heralds the development of burned out LN (stage 5 LN) which predisposes patients to thrombosis. Prophylactic anticoagulation plays an important role in the management of such patients. We describe a case of a 19 year old female with lupus nephritis and renal vein thrombosis that had extended into the inferior vena cava. Her serology was strikingly signicant for the absence of anti dsDNA antibody. The factors that predispose to the development of venous thrombosis in patients with Lupus Nephritis are discussed. In conclusion, negative anti dsDNA antibodies heralds the development of stage ve Lupus Nephritis which predisposes to thrombosis. Guidelines for prophylactic anticoagulation as per serum albumin levels are also discussed.

Obesity increases the risk of developing cancers for both males and females. This study investigated potential crosstalk between estradiol and leptin signaling pathways within the endometrium of high-fat-diet-induced obese ovariectomized mice to gain insight into possible links between obesity and endometrial cancer. We administered 17-β estradiol (0.2 μg/mouse subcutaneously) and/or recombinant mouse leptin (1 μg/g Bwt intraperitoneally.,) for 20 h to high-fat-diet-induced obese ovariectomized mice. The uterine tissues of experimental animals after treatments were studied by histological, immunohistochemical, quantitative real-time PCR (gene/miRNAs), and methylation-specific PCR analyses. Quantitative real-time PCR analysis revealed significantly increased expression of Cyclin d1, Esr1, Igf1, Igfbp2, Vegf, Oct4, and Pgr after estradiol and leptin co-treatment. Methylation-specific PCR results indicated that the hormonal dependent transcriptional regulation of Vegf, Igf1, and Pgr is independent of promoter methylation. The decreased expression of mmu- miR-204-5p after estradiol and leptin treatments correlated with the increased expression of long non-coding RNA Neat1. Insilico analysis confirmed the interaction of Neat1 and mmu- miR-204-5p and gene targets of mmu-miR-204-5p, including Igf1 were analyzed in this study. Immunohistochemical analyses revealed subcellular localization and increased expression of ESR, VEGF, phospho-Estrogen Receptor-α (pTyr537), and LEPR proteins following estradiol and leptin exposure. Overall, the data from our in vivo studies suggest the regulation of Neat1-mmu-miR-204-5p- Igf1 axis and associated gene expression changes in uterine tissue after estradiol and leptin co-treatment. In humans, long-term exposure to estradiol and leptin can alter endometrial homeostasis through the NEAT1-miR-204-5p-Igf1 axis and favor carcinogenic pathways, which provide mechanistic insight into the obesity-associated endometrial cancer.

An object plunging into a thickening suspension can be made to sink faster by applying orthogonal perturbations., Hundreds of YouTube videos show people running on cornstarch suspensions demonstrating that dense shear thickening suspensions solidify under impact. Such processes are mimicked by impacting and pulling out a plate from the surface of a thickening cornstarch suspension. Here, using both experiments and simulations, we show that applying fast oscillatory shear transverse to the primary impact or extension directions tunes the degree of solidification. The forces acting on the impacting surface are modified by varying the dimensionless ratio of the orthogonal shear to the compression and extension flow rate. Simulations show varying this parameter changes the number of particle contacts governing solidification. To demonstrate this strategy in an untethered context, we show the sinking speed of a cylinder dropped onto the suspension varies markedly by changing this dimensionless ratio. These results suggest applying orthogonal shear while people are running on cornstarch would de-solidify the suspension and cause them to sink.

Cells feel the tension of implanted and injected silicone materials., Silicones are commonly used for lubrication of syringes, encapsulation of medical devices, and fabrication of surgical implants. While silicones are generally viewed as relatively inert to the cellular milieu, they can mediate a variety of inflammatory responses and other deleterious effects, but the mechanisms underlying the bioactivity of silicones remain unresolved. Here, we report that silicone liquids and gels have high surface stresses that can strongly resist deformation at cellular length scales. Biomedical silicones, including syringe lubricants and fillings from FDA-approved breast implants, readily adsorb matrix proteins and activate canonical rigidity sensing pathways through their surface stresses. In 3D culture models, liquid silicone droplets support robust cellular adhesion and the formation of multinucleated monocyte-derived cell masses that recapitulate phenotypic aspects of granuloma formation in the foreign body response. Together, our findings implicate surface stress as a cellular stimulant that should be considered in application of silicones for biomedical purposes.

MicroRNAs regulate gene expression, and their diverse roles in the field of biomedicine are established and progressively increasing along with advancements in molecular biology techniques. The environment affects human health via genetic and epigenetic alterations. The study of cellular or circulating biomarkers offers help in the management of environmental toxicology by predicting environmental risk factors of any nature, such as air, metals and pesticides and other chemicals. Here, we review on the relationship of microRNAs as biomarkers and the toxicology of environmental agents. Concerning the effects of toxic agents in the environment and prediction of human exposure by biomarkers are still ongoing processes. It demands further researches using advanced research tools. Moreover, the studies dealing with toxicology-related miRNA changes and biomonitoring of environmental xenobiotics with altered miRNA expression will be highlighted in this review.