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Malaria is a life-threatening disease and one of the main causes of morbidity and mortality in the human population. The disease also results in a major socio-economic burden. The rapid spread of malaria epidemics in developing countries is exacerbated by the rise in drug-resistant parasites and insecticide-resistant mosquitoes. At present, malaria research is focused mainly on the development of drugs with increased therapeutic effects against Plasmodium parasites. However, a vaccine against the disease is preferable over treatment to achieve long-term control. Trials to develop a safe and effective immunization protocol for the control of malaria have been occurring for decades, and continue on today; still, no effective vaccines are available on the market. Recently, peptide-based vaccines have become an attractive alternative approach. These vaccines utilize short protein fragments to induce immune responses against malaria parasites. Peptide-based vaccines are safer than traditional vaccines, relatively inexpensive to produce, and can be composed of multiple T- and B-cell epitopes integrated into one antigenic formulation. Various combinations, based on antigen choice, peptide epitope modification and delivery mechanism, have resulted in numerous potential malaria vaccines candidates; these are presently being studied in both preclinical and clinical trials. This review describes the current landscape of peptide-based vaccines, and addresses obstacles and opportunities in the production of malaria vaccines.

Chikungunya virus (CHIKV) belongs to a group of mosquito-borne alphaviruses associated with acute and chronic arthropathy, with peripheral and limb joints most commonly affected. Using a mouse model of CHIKV infection and arthritic disease, we show that CHIKV replication and the ensuing foot arthropathy were dramatically reduced when mice were housed at 30°C, rather than the conventional 22°C. The effect was not associated with a detectable fever, but was dependent on type I interferon responses. Bioinformatics analyses of RNA-Seq data after injection of poly(I:C)/jetPEI suggested the unfolded protein response and certain type I interferon responses are promoted when feet are slightly warmer. The ambient temperature thus appears able profoundly to effect anti-viral activity in the periphery, with clear consequences for alphaviral replication and the ensuing arthropathy. These observations may provide an explanation for why alphaviral arthropathies are largely restricted to joints of the limbs and the extremities.

We conducted a study among healthcare workers (HCWs) exposed to patients with severe acute respiratory syndrome (SARS) before infection control measures were instituted. Of all exposed HCWs, 7.5% had asymptomatic SARS-positive cases. Asymptomatic SARS was associated with lower SARS antibody titers and higher use of masks when compared to pneumonic SARS.

In alpine ecosystems, elevation broadly functions as a steep thermal gradient, with plant communities exposed to regular fluctuations in hot and cold temperatures. These conditions lead to selective filtering, potentially contributing to species-level variation in thermal tolerance and population-level genetic divergence. Few studies have explored the breadth of alpine plant thermal tolerances across a thermal gradient or the underlying genetic variation thereof. We measured photosystem heat (Tcrit-hot) and cold (Tcrit-cold) thresholds of ten Australian alpine species across elevation gradients and characterised their neutral genetic variation. To reveal the biogeographical drivers of present-day genetic signatures, we also reconstructed temporal changes in habitat suitability across potential distributional ranges. We found intraspecific variation in thermal thresholds, but this was not associated with elevation, nor underpinned by genetic differentiation on a local scale. Instead, regional population differentiation and considerable homozygosity within populations may, in part, be driven by distributional contractions, long-term persistence, and migrations following habitat suitability. Our habitat suitability models suggest that cool-climate-distributed alpine plants may be threatened by a warming climate. Yet, the observed wide thermal tolerances did not reflect this vulnerability. Conservation efforts should seek to understand variations in species-level thermal tolerance across alpine microclimates. [ABSTRACT FROM AUTHOR]

The THz spectrum (0.1-10 THz) is a region between optics and electronics, and it is still not fully explored and is unlicensed. Recent studies show that it will bring a revolution in technology, especially in the field of communication. Future communication technologies such as 6G and Terabit DSL will utilize this THz band as it has the capability to support high data rates in Tbps. For designing an efficient system that propagates these THz waves with low loss, it is required to understand the propagation channel properly. THz channel modeling is at its infancy stage, and a detailed investigation of channel behavior is required to study the efficient propagation of THz waves. In this study, the methods applied to the modeling of the THz channel are discussed in detail. Although channel modeling is a broad topic here only the methods and techniques are discussed along with their advantages and limitations. Lastly, the challenges and the future direction in the field of THz channel modeling are also discussed. [ABSTRACT FROM AUTHOR]

In this paper, a comparison microwave method between Transmission and Reflection using a Coaxial Cable and complimentary double split ring resonator (CDSRR) for characterization of magneto-dielectric material is proposed. This method enables the determination of both relative permittivity and permeability of magneto-dielectric material. The CDSRR resonates at 3.46 GHz with a quality factor of 127 in unloaded condition. To determine the effects of permittivity and permeability on the shift of resonant frequency, the electric and magnetic fields are localized in two separate zones in the CDSRR sensor. Prediction formulas are proposed to extract the value of real permittivity and permeability from S21 parameter. For Transmission/Reflection Method, to extract the dielectric and magnetic properties, Nicolson-Ross-Weir (NRW) are used. The prototypes of proposed sensors are fabricated on a ROGERS 3003 and tested for validation of their functionality. A good agreement between the measured data using Transmission/Reflection Method and CDSRR sensor is observed. [ABSTRACT FROM AUTHOR]

A comparison between storm‐time TIMED/GUVI FUV spectra in thermospheric composition disturbed (O/N2 <∼140 km> depleted and NO <∼110 km> enhanced) and undisturbed regions reveals the following features: (1) A clear decrease in N2 LBHS (140–150 nm) band intensities compared to that between 150 and 160 nm; (2) A significant spectral decrease around O 164.1 nm; (3) Two enhanced peaks between 170 and 185 nm. The feature (2) is clearly due to atomic oxygen density decrease in the low thermosphere. The feature (3) is caused by storm‐time production and transport of nitric oxide. An AURIC simulation reproduced feature (1) confirming that storm‐time enhancement in O2 density (∼120–170 km) and the wavelength dependent O2 absorption cross section are the source of observed feature (1). On the other hand, the feature (1) was not observed in the regions without O/N2 depletion. This further supports that O2 density enhancement is responsible for feature (1). Plain Language Summary: Observations by a FUV spectrograph imager on NASA TIMED satellite revealed two interesting features in the storm‐time disturbed thermosphere: (1) a relative decrease in N2 LBH intensities at 140–150 nm versus 150–160 nm, (2) significant decrease in O 164.1 nm radiance and enhanced emission between 170 and 185 nm. The feature (2) is well known and due to O density depletion and production of nitric oxide. The feature is not well understood. A model simulation indicates the feature (1) is due to storm‐time O2 density increase and wavelength dependent O2 absorption cross section which peaked around 140 nm. This result indicates that FUV spectrograph imager is capable to detect storm‐time O2 density changes. Key Points: (1) FUV spectral difference between storm‐quiet time shows a relative decrease in N2 LBH intensities at 140–150 nm versus 150–160 nmThe FUV spectrograph difference between undisturbed regions did not show the above feature(3) Simulations confirm indicate that enhanced O2 density and absorption causes the observed FUV spectral differences [ABSTRACT FROM AUTHOR]

Abstract The mechanisms underlying myopia pathogenesis are not well understood. Using publicly-available human and animal datasets, we expound on the roles of known, implicated proteins, and new myopia-related signaling pathways were hypothesized. Proteins identified from human serum or ocular fluids, and from ocular tissues in myopic animal models, were uploaded and analyzed with the QIAGEN Ingenuity Pathway Analysis (IPA) software (March 2023). With each IPA database update, more potentially-relevant proteins and signaling pathways previously unavailable during data acquisition are added, allowing extraction of novel conclusions from existing data. Canonical pathway analysis was used to analyze these data and calculate an IPA activation z-score—which indicates not only whether an association is significant, but also whether the pathway is likely activated or inhibited. Cellular immune response and cytokine signaling were frequently found to be affected in both human and animal myopia studies. Analysis of two publicly-available proteomic datasets highlighted a potential role of the innate immune system and inflammation in myopia development, detailing specific signaling pathways involved such as Granzyme A (GzmA) and S100 family signaling in the retina, and activation of myofibroblast trans-differentiation in the sclera. This perspective in myopia research may facilitate development of more effective and targeted therapeutic agents.

Abstract Retina-derived growth signals relayed from the choroid to the sclera cause remodeling of the extracellular scleral matrix, resulting in myopic ocular elongation. However, to the best of our knowledge, no studies have assessed changes in choroidal stromal biomechanical properties during myopia progression. Here we utilized 7 µm-resolution scanning acoustic microscopy (SAM) to assess biomechanical properties (bulk modulus (K) and mass density (rho)) of choroidal stroma from guinea pig eyes with form-deprivation (FD) induced myopia. The choroidal stroma had considerable intrinsic strength arising from its biomechanical properties and these were differentially affected by myopia in central and peripheral regions. Choroidal stromal biomechanical values were also highly correlated with those in adjacent scleral regions, and the choroidal stromal-scleral association was stronger in myopic eyes. Biomechanical changes observed in the choroidal stroma of myopic eyes were mirrored to those observed in the adjacent sclera. These findings suggest that choroidal stromal remodeling may accompany myopia and open the door to the source of the signals that cause scleral remodeling in myopia.

Abstract Background Breast cancer (BC) is a complex disease with profound genomic aberrations. However, the underlying molecular disparity influenced by age and ethnicity remains elusive. Methods In this study, we aimed to investigate the molecular properties of 843 primary and metastatic BC patients enrolled in the K-MASTER program. By categorizing patients into two distinct age subgroups, we explored their unique molecular properties. Additionally, we leveraged large-scale genomic data from the TCGA and MSK-IMPACT studies to examine the ethnic-driven molecular and clinical disparities. Results We observed a high prevalence of PI3KCA mutations in K-MASTER HER2 + tumors, particularly in older patients. Moreover, we identified increased mutation rates in DNA damage response molecules, including ARID1A, MSH6, and MLH1. The K-MASTER patients were mainly comprised of triple-negative breast cancer (TNBC) and HER2-positive tumors, while the TCGA and MSK-IMPACT cohorts exhibited a predominance of hormone receptor-positive (HR +) subtype tumors. Importantly, GATA3 mutations were less frequently observed in East Asian patients, which correlated with poor clinical outcomes. In addition to characterizing the molecular disparities, we developed a gradient-boosting multivariable model to identify a new molecular signature that could predict the therapeutic response to platinum-based chemotherapy. Conclusions Our findings collectively provide unprecedented insights into the significance of age and ethnicity on the molecular and clinical characteristics of BC patients.