Enhancing breast cancer classification via histopathological image analysis: Leveraging self-supervised contrastive learning and transfer learning.

Breast cancer, a significant threat to women's health, demands early detection. Automating histopathological image analysis offers a promising solution to enhance efficiency and accuracy in diagnosis. This study addresses the challenge of breast cancer histopathological image classification by leveraging the ResNet architecture, known for its depth and skip connections. In this work, two distinct approaches were pursued, each driven by unique motivations. The first approach aimed to improve the learning process through self-supervised contrastive learning. It utilizes a small subset of the training data for initial model training and progressively expands the training set by incorporating confidently labeled data from the unlabeled pool, ultimately achieving a reliable model with limited training data. The second approach focused on optimizing the architecture by combining ResNet50 and Inception module to get a lightweight and efficient classifier. The dataset utilized in this work comprises histopathological images categorized into benign and malignant classes at varying magnification levels (40X, 100X, 200X, 400X), all originating from the same source image. The results demonstrate state-of-the-art performance, achieving 98% accuracy for images magnified at 40X and 200X, and 94% for 100X and 400X. Notably, the proposed architecture boasts a substantially reduced parameter count of approximately 3.6 million, contrasting with existing leading architectures, which possess parameter sizes at least twice as large.

FABP7 drives an inflammatory response in human astrocytes and is upregulated in Alzheimer's disease.

Alzheimer's disease (AD), the most common cause of dementia in the elderly, is characterized by the accumulation of intracellular neurofibrillary tangles, extracellular amyloid plaques, and neuroinflammation. In partnership with microglial cells, astrocytes are key players in the regulation of neuroinflammation. Fatty acid binding protein 7 (FABP7) belongs to a family of conserved proteins that regulate lipid metabolism, energy homeostasis, and inflammation. FABP7 expression is largely restricted to astrocytes and radial glia-like cells in the adult central nervous system. We observed that treatment of primary hippocampal astrocyte cultures with amyloid ß fragment 25-35 (Aß25-35) induces FABP7 upregulation. In addition, FABP7 expression is upregulated in the brain of APP/PS1 mice, a widely used AD mouse model. Co-immunostaining with specific astrocyte markers revealed increased FABP7 expression in astrocytes. Moreover, astrocytes surrounding amyloid plaques displayed increased FABP7 staining when compared to non-plaque-associated astrocytes. A similar result was obtained in the brain of AD patients. Whole transcriptome RNA sequencing analysis of human astrocytes differentiated from induced pluripotent stem cells (i-astrocytes) overexpressing FABP7 identified 500 transcripts with at least a 2-fold change in expression. Gene Ontology enrichment analysis identified (i) positive regulation of cytokine production and (ii) inflammatory response as the top two statistically significant overrepresented biological processes. We confirmed that wild-type FABP7 overexpression induces an NF-κB-driven inflammatory response in human i-astrocytes. On the other hand, the expression of a ligand-binding impaired mutant FABP7 did not induce NF-κB activation. Together, our results suggest that the upregulation of FABP7 in astrocytes could contribute to the neuroinflammation observed in AD.

Single-pumped gain profile for a superluminal ring laser.

We present an approach for realizing a superluminal ring laser using a single isotope of atomic Rb vapor by producing electromagnetically induced transparency (EIT) in self-pumped Raman gain. Only a single pump laser is used for generating a Raman gain profile containing a dip at its center. The position and depth of this dip can be tuned by adjusting the intensity of the pump laser, allowing for optimizing the degree of enhancement in sensitivity within a certain operating range. This approach represents a significant simplification of the design of superluminal lasers compared to the approaches demonstrated in previous studies. We demonstrate experimentally the realization of this scheme using transitions within the D1 and the D2 manifolds of 85Rb. Numerical simulations based on an approximate model show close agreement with the experimental results.

Gßγ subunits colocalize with RNA polymerase II and regulate transcription in cardiac fibroblasts.

Gßγ subunits mediate many different signaling processes in various compartments of the cell, including the nucleus. To gain insight into the functions of nuclear Gßγ signaling, we investigated the functional role of Gßγ signaling in the regulation of GPCR-mediated gene expression in primary rat neonatal cardiac fibroblasts. We identified a novel, negative, regulatory role for the Gß1γ dimer in the fibrotic response. Depletion of Gß1 led to derepression of the fibrotic response at the mRNA and protein levels under basal conditions and an enhanced fibrotic response after sustained stimulation of the angiotensin II type I receptor. Our genome-wide chromatin immunoprecipitation experiments revealed that Gß1 colocalized and interacted with RNA polymerase II on fibrotic genes in an angiotensin II-dependent manner. Additionally, blocking transcription with inhibitors of Cdk9 prevented association of Gßγ with transcription complexes. Together, our findings suggest that Gß1γ is a novel transcriptional regulator of the fibrotic response that may act to restrict fibrosis to conditions of sustained fibrotic signaling. Our work expands the role for Gßγ signaling in cardiac fibrosis and may have broad implications for the role of nuclear Gßγ signaling in other cell types.

Acoustic Tweezer-Modulated Biomimetic Patterned Particle-Polymer Composite for Water Vapor Harvesting.

With the recent threat of climate change and global warming, ensuring access to safe drinking water is a great challenge in many areas worldwide. Designing functional materials for capturing water from natural resources like fog and mist has become one of the key research areas to maximize the production of clean water. From this aspect, nature is a great source for designing bioinspired functional materials as some of the plant leaves and animal exoskeletons can harness water and then store it to save themselves from arid, xeric conditions. Inspired by the Stenocara beetle, we have designed a composite surface structure with periodic islands made of aluminum microparticles surrounded by poly(dimethylenesiloxane) (PDMS). An acoustic tweezer-based method was used to fabricate the bioinspired composite structures, where surface acoustic waves at specific frequencies and amplitudes are applied to align the microparticles as islands in the polymer matrix. An oxygen plasma etching step was applied to expose the microparticles on the PDMS surface. The average water harvesting efficiencies for structures made with 120 and 80 kHz acoustic frequencies and 1 hour etching time were found to be 9.41 and 8.84 g cm-2 h-1, respectively. The acoustically patterned biomimetic composite surface showed higher water harvesting efficiency compared with completely hydrophobic PDMS and hydrophilic aluminum surfaces, demonstrating the advantages of the bioinspired composite material design and acoustic-assisted manufacturing technique. The biomimetic fog water harvesting material is a promising avenue to fulfill the demand for a cost-effective, sustainable, and energy-efficient solution to safe drinking water.

Observation of a highly superluminal laser employing optically pumped Raman gain and depletion.

In this paper, we report a Raman laser which is extremely sensitive to a variation of the cavity length, using a scheme employing two stable isotopes of Rb. One isotope is used for producing a broad gain spectrum via the optically pumped Raman gain process, while the other is used for producing a narrow dip via the optically pumped Raman depletion process. By tuning the frequencies of the two Raman pumps, the center frequencies of the gain and dip can be aligned to the same frequency. This approach allows tuning of the gain and dip parameters independently over a broad range of operating conditions. With such a configuration, we can produce a negative dispersion around the two-photon resonance frequency in the vapor cell, which leads to a group index that is close to zero. By theoretically matching the experimental observations, we can infer that the sensitivity of such laser is enhanced by a factor of more than 2800, which is nearly a factor of three larger than the highest value reported previously using a different approach.

Brachial plexus anatomy in the miniature swine as compared to human.

Brachial plexus injury (BPI) occurs when the brachial plexus is compressed, stretched, or avulsed. Although rodents are commonly used to study BPI, these models poorly mimic human BPI due to the discrepancy in size. The objective of this study was to compare the brachial plexus between human and Wisconsin Miniature SwineTM (WMSTM ), which are approximately the weight of an average human (68-91 kg), to determine if swine would be a suitable model for studying BPI mechanisms and treatments. To analyze the gross anatomy, WMS brachial plexuses were dissected both anteriorly and posteriorly. For histological analysis, sections from various nerves of human and WMS brachial plexuses were fixed in 2.5% glutaraldehyde, and postfixed with 2% osmium tetroxide. Subsequently paraffin sections were counter-stained with Masson's Trichrome. Gross anatomy revealed that the separation into three trunks and three cords is significantly less developed in the swine than in human. In swine, it takes the form of upper, middle, and lower systems with ventral and dorsal components. Histological evaluation of selected nerves revealed differences in nerve trunk diameters and the number of myelinated axons in the two species. The WMS had significantly fewer myelinated axons than humans in median (p = 0.0049), ulnar (p = 0.0002), and musculocutaneous nerves (p = 0.0454). The higher number of myelinated axons in these nerves for humans is expected because there is a high demand of fine motor and sensory functions in the human hand. Due to the stronger shoulder girdle muscles in WMS, the WMS suprascapular and axillary nerves were larger than in human. Overall, the WMS brachial plexus is similar in size and origin to human making them a very good model to study BPI. Future studies analyzing the effects of BPI in WMS should be conducted.

Correlated-Weighted Statistically Modeled Contourlet and Curvelet Coefficient Image-Based Breast Tumor Classification Using Deep Learning.

Deep learning-based automatic classification of breast tumors using parametric imaging techniques from ultrasound (US) B-mode images is still an exciting research area. The Rician inverse Gaussian (RiIG) distribution is currently emerging as an appropriate example of statistical modeling. This study presents a new approach of correlated-weighted contourlet-transformed RiIG (CWCtr-RiIG) and curvelet-transformed RiIG (CWCrv-RiIG) image-based deep convolutional neural network (CNN) architecture for breast tumor classification from B-mode ultrasound images. A comparative study with other statistical models, such as Nakagami and normal inverse Gaussian (NIG) distributions, is also experienced here. The weighted entitled here is for weighting the contourlet and curvelet sub-band coefficient images by correlation with their corresponding RiIG statistically modeled images. By taking into account three freely accessible datasets (Mendeley, UDIAT, and BUSI), it is demonstrated that the proposed approach can provide more than 98 percent accuracy, sensitivity, specificity, NPV, and PPV values using the CWCtr-RiIG images. On the same datasets, the suggested method offers superior classification performance to several other existing strategies.

Rhesus monkeys as a translational model for late-onset Alzheimer's disease.

Age is a major risk factor for late-onset Alzheimer's disease (AD) but seldom features in laboratory models of the disease. Furthermore, heterogeneity in size and density of AD plaques observed in individuals are not recapitulated in transgenic mouse models, presenting an incomplete picture. We show that the amyloid plaque microenvironment is not equivalent between rodent and primate species, and that differences in the impact of AD pathology on local metabolism and inflammation might explain established differences in neurodegeneration and functional decline. Using brain tissue from transgenic APP/PSEN1 mice, rhesus monkeys with age-related amyloid plaques, and human subjects with confirmed AD, we report altered energetics in the plaque microenvironment. Metabolic features included changes in mitochondrial distribution and enzymatic activity, and changes in redox cofactors NAD(P)H that were shared among species. A greater burden of lipofuscin was detected in the brains from monkeys and humans of advanced age compared to transgenic mice. Local inflammatory signatures indexed by astrogliosis and microglial activation were detected in each species; however, the inflamed zone was considerably larger for monkeys and humans. These data demonstrate the advantage of nonhuman primates in modeling the plaque microenvironment, and provide a new framework to investigate how AD pathology might contribute to functional loss.

A Fatal Case of Powassan Virus Encephalitis.

Powassan virus (POWV) is a flavivirus of the tick-borne encephalitis serogroup that causes a rare and potentially life-threatening neuroinvasive disease. Viral transmission occurs during zoonotic spillover from mammals by the bite of an infected tick in endemic regions of North America. The number of reported POWV cases has recently increased in the United States. We report a fatal case of POWV meningoencephalomyelitis in Northern Wisconsin following a documented tick bite. Histologic examination of the brain demonstrated widespread intraparenchymal and perivascular lymphohistocytic infiltration, microglial nodule formation, and marked neuronal degeneration, most severely involving the substantia nigra, anterior horn of spinal cord and cerebellum. Although no viral inclusions were seen in routine light microscopy, electron microscopy identified multiple neurons containing cytoplasmic clusters of virus particles ∼50 nm in diameter. POWV infection was confirmed using immunohistochemical analysis and reverse transcription-polymerase chain reaction. This report demonstrates in detail regional central nervous system involvement and ultrastructural characteristics of Powassan viral particles by transmission electron microscopy, while highlighting the utility of evaluating fixed autopsy tissues in cases of unexplained meningoencephalomyelitis.

Agricultural Farm-Related Injuries in Bangladesh and Convenient Design of Working Hand Tools.

Injuries during cultivation of land are the significant causes of recession for an agricultural country like Bangladesh. Thousands of tools are used in agricultural farm having much probability of getting injury at their workplaces. For the injury prevention, proper hand tool designs need to be recommended with ergonomic evaluations. This paper represents the main causes of agricultural injuries among the Bangladeshi farmers. Effective interventions had been discussed in this paper to reduce the rate of injury. This study was carried out in the Panchagarh district of Bangladesh. Data on 434 agricultural injuries were collected and recorded. About 67% injuries of all incidents were due to hand tools, and the remaining 33% were due to machinery or other sources. Though most of the injuries were not serious, about 22% injuries were greater than or equal to AIS 2 (Abbreviated Injury Scale). The practical implication of this study is to design ergonomically fit agricultural hand tools for Bangladeshi farmers in order to avoid their injuries.

Neck Rhabdoid Tumors: Clinical Features and Consideration of Autologous Stem Cell Transplant.

Extrarenal malignant rhabdoid tumors (MRT) have a poor prognosis despite aggressive therapy. Adding high-dose chemotherapy with autologous stem cell rescue (HDC-ASCR) as consolidative therapy for MRT is controversial. We describe 2 patients, age 13 years and 19 months, with unresectable neck MRT. After chemotherapy and radiotherapy, both underwent HDC-ASCR and remain in remission over 4 years later. We reviewed all published cases of neck MRT, and found poorer outcomes and more variable age of presentation and time to progression than MRT at other sites. Neck MRT may represent a higher-risk subset of MRT, and addition of HDC-ASCR merits consideration.

Theoretical modeling and experimental demonstration of Raman probe induced spectral dip for realizing a superluminal laser.

We have demonstrated experimentally a Diode-Pumped Alkali Laser (DPAL) with a Raman resonance induced dip in the center of the gain profile, in order to produce an anomalous dispersion, necessary for making the laser superluminal. Numerical calculations match closely with experimental results, and indicate that the laser is operating superluminally, with the group index far below unity (~0.00526) at the center of the dip. The estimated factor of enhancement in the sensitivity to cavity length perturbation is ~190, approximately equaling the inverse of the group index. This enhancement factor can be made much higher via optimal tuning of parameters. Such a laser has the potential to advance significantly the field of high-precision metrology, with applications such as vibrometry, accelerometry, and rotation sensing.

The sulci of the inferior surface of the temporal lobe: An anatomical study.

Understanding the anatomy of temporal lobe sulci and their variations can allow for safer neurosurgical approaches. Although the inferior temporal sulci and their relations to each other has been described by several authors, the nomenclature used has not been universal. The aim of this study was to investigate the anatomic features of the three main sulci of the inferior temporal lobe and provide a simple description of complex patterns among these sulci. Sulcal variations and their relations were examined in seventy formalin-fixed, adult cadaveric cerebral hemispheres. We recommend a simple but modified classification specifically for anatomic variations of the rhinal and collateral sulci. Furthermore, we describe the frequency of occipitotemporal sulci that contain 5 and 6 segments, not previously mentioned. The length and depth of all sulci were measured in all samples. Additionally, more detailed results regarding the patterns, courses, connections, relationships and measurements were given. Understanding of the complex anatomy of this clinically important region is of benefit to neurosurgeons, providing necessary guidance for neurosurgical approaches to the inferior surface of the temporal lobe. Clin. Anat. 29:932-942, 2016. © 2016 Wiley Periodicals, Inc.

Gßγ subunits-Different spaces, different faces.

Gßγ subunits play key roles in modulation of canonical effectors in G protein-coupled receptor (GPCR)-dependent signalling at the cell surface. However, a number of recent studies of Gßγ function have revealed that they regulate a large number of molecules at distinct subcellular sites. These novel, non-canonical Gßγ roles have reshaped our understanding of how important Gßγ signalling is compared to our original notion of Gßγ subunits as simple negative regulators of Gα subunits. Gßγ dimers have now been identified as regulators of transcription, anterograde and retrograde trafficking and modulators of second messenger molecule generation in intracellular organelles. Here, we review some recent advances in our understanding of these novel non-canonical roles of Gßγ.

Estimation of Soil Erosion Dynamics in the Koshi Basin Using GIS and Remote Sensing to Assess Priority Areas for Conservation.

High levels of water-induced erosion in the transboundary Himalayan river basins are contributing to substantial changes in basin hydrology and inundation. Basin-wide information on erosion dynamics is needed for conservation planning, but field-based studies are limited. This study used remote sensing (RS) data and a geographic information system (GIS) to estimate the spatial distribution of soil erosion across the entire Koshi basin, to identify changes between 1990 and 2010, and to develop a conservation priority map. The revised universal soil loss equation (RUSLE) was used in an ArcGIS environment with rainfall erosivity, soil erodibility, slope length and steepness, cover-management, and support practice factors as primary parameters. The estimated annual erosion from the basin was around 40 million tonnes (40 million tonnes in 1990 and 42 million tonnes in 2010). The results were within the range of reported levels derived from isolated plot measurements and model estimates. Erosion risk was divided into eight classes from very low to extremely high and mapped to show the spatial pattern of soil erosion risk in the basin in 1990 and 2010. The erosion risk class remained unchanged between 1990 and 2010 in close to 87% of the study area, but increased over 9.0% of the area and decreased over 3.8%, indicating an overall worsening of the situation. Areas with a high and increasing risk of erosion were identified as priority areas for conservation. The study provides the first assessment of erosion dynamics at the basin level and provides a basis for identifying conservation priorities across the Koshi basin. The model has a good potential for application in similar river basins in the Himalayan region.

High-speed modulation in ladder transitions in Rb atoms using high-pressure buffer gas.

Modulators using atomic systems are often limited in speed by the rate of spontaneous emission. One approach for overcoming this limit is to make use of a buffer gas such as Ethane, which causes rapid fine structure mixing of the P(1/2) and P(3/2) states, and broadens the absorption spectra of the D1 and D2 lines in alkali atoms. Employing this effect, we show that one can achieve high speed modulation using ladder transitions in Rubidium. We demonstrate a 100-fold increase, due to the addition of the buffer gas, in the modulation bandwidth using the 5S-5P-5D cascade system. The observed bandwidth of ~200 MHz is within a factor of 2.5 of the upper bound of ~0.51 GHz for the system used, and is limited by various practical constraints in our experiment. We also present numerical simulations for the system and predict that a much higher modulation speed should be achievable under suitable conditions. In combination with a tapered nano fiber or a SiN waveguide, it has the potential to be used for high-speed, low-power all-optical modulation.

Gß4γ1 as a modulator of M3 muscarinic receptor signalling and novel roles of Gß1 subunits in the modulation of cellular signalling.

Much is known about the how Gßγ subunits regulate effectors in response to G protein-coupled receptor stimulation. However, there is still a lot we don't know about how specific combinations of Gß and Gγ are wired into different signalling pathways. Here, using an siRNA screen for different Gß and Gγ subunits, we examined an endogenous M3 muscarinic receptor signalling pathway in HEK 293 cells. We observed that Gß(4) subunits were critical for calcium signalling and a downstream surrogate measured as ERK1/2 MAP kinase activity. A number of Gγ subunits could partner with Gß(4) but the best coupling was seen via Gß(4)γ(1). Intriguingly, knocking down Gß(1) actually increased signalling through the M3-mAChR most likely via an increase in Gß(4) levels. We noted that Gß(1) occupies the promoter of Gß(4) and may participate in maturation of its mRNA. This highlights a new role for Gßγ signalling beyond their canonical roles in cellular signalling.

Optically controlled waveplate at a telecom wavelength using a ladder transition in Rb atoms for all-optical switching and high speed Stokesmetric imaging.

We demonstrate an optically controlled waveplate at ~1323 nm using the 5S(1/2)-5P(1/2)-6S(1/2) ladder transition in a Rb vapor cell. The lower leg of the transitions represents the control beam, while the upper leg represents the signal beam. We show that we can place the signal beam in any arbitrary polarization state with a suitable choice of polarization of the control beam. Specifically, we demonstrate a differential phase retardance of ~180 degrees between the two circularly polarized components of a linearly polarized signal beam. We also demonstrate that the system can act as a Quarter Wave plate. The optical activity responsible for the phase retardation process is explained in terms of selection rules involving the Zeeman sublevels. As such, the system can be used to realize a fast Stokesmetric imaging system with a speed of ~3 MHz. When implemented using a tapered nano fiber embedded in a vapor cell, this system can be used to realize an ultra-low power all-optical switch as well as a Quantum Zeno Effect based all-optical logic gate by combining it with an optically controlled polarizer, previously demonstrated by us. We present numerical simulations of the system using a comprehensive model which incorporates all the relevant Zeeman sub-levels in the system, using a novel algorithm recently developed by us for efficient computation of the evolution of an arbitrary large scale quantum system.

Incorporation of polar Mellin transform in a hybrid optoelectronic correlator for scale and rotation invariant target recognition.

In this paper, we show that our proposed hybrid optoelectronic correlator (HOC), which correlates images using spatial light modulators (SLMs), detectors, and field-programmable gate arrays (FPGAs), is capable of detecting objects in a scale and rotation invariant manner, along with the shift invariance feature, by incorporating polar Mellin transform (PMT). For realistic images, we cut out a small circle at the center of the Fourier transform domain, as required for PMT, and illustrate how this process corresponds to correlating images with real and imaginary parts. Furthermore, we show how to carry out shift, rotation, and scale invariant detection of multiple matching objects simultaneously, a process previously thought to be incompatible with PMT-based correlators. We present results of numerical simulations to validate the concepts.