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The ultraviolet resonance Raman (UVRR) spectra of the two proteins bovine serum albumin (BSA) and human serum albumin (HSA) in an aqueous solution are compared with the aim to distinguish between them based on their very similar amino acid composition and structure and to obtain signals from tryptophan that has only very few residues. Comparison of the protein spectra with solutions of tryptophan, tyrosine, and phenylalanine in comparative ratios as in the two proteins shows that at an excitation wavelength of 220 nm, the spectra are dominated by the strong resonant contribution from these three amino acids. While the strong enhancement of two and one single tryptophan residue in BSA and HSA, respectively, results in pronounced bands assigned to fundamental vibrations of tryptophan, its weaker overtones and combination bands do not play a major role in the spectral range above 1800 cm -1 . There, the protein spectra clearly reveal the signals of overtones and combination bands of phenylalanine and tyrosine. Assignments of spectral features in the range of Raman shifts from 3800 to 5100 cm -1 to combinations comprising fundamentals and overtones of tyrosine were supported by spectra of amino acid mixtures that contain deuterated tyrosine. The information in the high-frequency region of the UVRR spectra could provide information that is complementary to near-infrared absorption spectroscopy of the proteins.

The luminescence of In x Ga 1- x N nanowires (NWs) is frequently reported with large red-shifts as compared to the theoretical value expected from the average In content. Both compositional fluctuations and radial built-in fields were considered accountable for this effect, depending on the size, structure, composition, and surrounding medium of the NWs. In the present work, the emission properties of InGaN/GaN NWs grown by plasma-assisted molecular beam epitaxy are investigated in a comprehensive study combining ultraviolet-Raman and photoluminescence spectroscopy (PL) on vertical arrays, polarization-dependent PL on bundles of a few NWs, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, and calculations of the band profiles. The roles of inhomogeneous In distribution and radial fields in the context of optical emission properties are addressed. The radial built-in fields are found to be modest, with a maximum surface band bending below 350 meV. On the other hand, variations in the local In content have been observed that give rise to potential fluctuations whose impact on the emission properties is shown to prevail over band-bending effects. Two luminescence bands with large positive and moderate negative polarization ratios of ≈+80% and ≤-60%, respectively, were observed. The red-shift in the luminescence is associated with In-rich inclusions in the NWs due to thermodynamic decomposition during growth. The negative polarization anisotropy is suggested to result from spontaneously formed superlattices in the In-rich regions of the NWs. The NWs show a preferred orthogonal absorption due to the dielectric boundary conditions and highlight the extreme sensitivity of these structures towards light polarization.

We report the first evidence of Raman scattering from surface phonons of a pristine metal surface. Our study reveals a Raman-active surface vibrational resonance on Cu(110) with a surprisingly large scattering efficiency. With the incident photon energy close to the energy of the Cu(110) surface state electronic transition, the Raman scattering from the surface optical resonance can be significantly enhanced, while any contribution from bulk phonons is absent.

In the U.S., approximately half of maids and housekeeping cleaners are Latino or Hispanic, while the vast majority are women (88.3%). This largely immigrant, underserved workforce faces complex factors, which may contribute to adverse health outcomes. To understand relevant barriers and challenges, this mixed-methods study explored the environmental health needs of a heterogeneous group of Latinas in New Jersey (NJ) who clean occupationally, and consisted of 3 focus groups (N = 15) with a cross-sectional survey (N = 9), both conducted in Spanish. Participants were recruited from community-based English as a Second Language classes in Hackensack, NJ. Analysis of focus group audio recordings included descriptive and in vivo coding followed by inductive coding to explore thematic analysis. The survey responses were evaluated using descriptive statistics. As per the survey results, the environmental health needs of this population include sore muscles, back problems, asthma, other respiratory issues, migraine or headache, and skin issues (rash, etc.). In the group discussions, the roles of genetics, food, and chemical exposures in cancer etiology were of great interest and a variety of opinions on the topic were explored. Both the focus group discussions and survey responses suggested that this population also faces barriers including lack of training, chemical exposures and inadequate personal protective equipment (PPE). These barriers are compounded by daily environmental exposures from personal home cleaning practices. The development of culturally- and linguistically-appropriate interventions are warranted to better protect the health of essential occupational cleaners who keep homes, businesses and schools clean., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Focus groups were facilitated by ES, who had no supervisory and/or professional relationship with the participants, as well as FCB, certified in Spanish/English translation, and APC, who were both volunteer instructors for the ESL classes. Study team members did not receive any compensation for their time. Participants received a $25 gift card for their participation., (© The Author(s) 2022.)

Background: In the United States, 88.3% of all 1,163,000 maids and housekeeping cleaners are female, and approximately half of them Latinas. Latinas are understudied and underrepresented in health research, particularly involving chemical exposure in cleaning practices, lack of job training, and inadequate access to personal protective equipment. The purpose of this study is twofold: 1) to examine the knowledge (via training experiences), attitudes and behaviors of a heterogeneous group of Latinas who clean occupationally and 2) to assess their cleaning practices at work and at home., Methods: This mixed-method study consisted of two phases: 1) three focus groups to explore knowledge (via training experiences), attitudes, and behaviors regarding cleaning practices (N = 15) and 2) a 43-question cross-sectional survey. Focus group audio recordings were analyzed using descriptive and in vivo coding and then coded inductively to explore thematic analysis. Statistical analysis of the survey evaluated means, frequency and percentage for each of the responses., Results: Participants (n = 9) were women (mean age = 48.78 and SD = 6.72) from South America (n = 5), Mexico (n = 1), El Salvador (n = 1) and Dominican Republic (n = 2). The mean length of time living in the US was 18.78 years and over half (55.6%) worked in the cleaning industry for 10 or more years. Findings from the three focus groups (n = 15) included that training in cleaning often occurred informally at a very young age at home. Participants reported cleaning in groups where tasks are rotated and/or shared. Most were the primary person cleaning at home, suggesting increased exposure. Gloves and masks were the most frequently used PPE, but use was not consistent. For participants who purchase their own products, driving factors included price, smell and efficacy. Some participants used products supplied or preferred by the employer., Conclusions: Latinas in cleaning occupations face a range of social and health barriers including lack of safety and health training, inadequate PPE and low literacy. To address these issues, the development of an intervention is warranted to provide training and resources for this critical population of essential workers., (© 2021. The Author(s).)

The ultraviolet resonance Raman spectra of the adenine-containing enzymatic redox cofactors nicotinamide adenine dinucleotide and flavin adenine dinucleotide in aqueous solution of physiological concentration are compared with the aim of distinguishing between them and their building block adenine in potential co-occurrence in biological materials. At an excitation wavelength of 266 nm, the spectra are dominated by the strong resonant contribution from adenine; nevertheless, bands assigned to vibrational modes of the nicotinamide and the flavin unit are found to appear at similar signal strength. Comparison of spectra measured at pH 7 with data obtained pH 10 and pH 3 shows characteristic changes when pH is increased or lowered, mainly due to deprotonation of the flavin and nicotinamide moieties, and protonation of the adenine, respectively.

Two-dimensional rare-earth silicide layers deposited on silicon substrates have been intensively investigated in the last decade, as they can be exploited both as Ohmic contacts or as photodetectors, depending on the substrate doping. In this study, we characterize rare-earth silicide layers on the Si(111) surface by a spectroscopic analysis. In detail, we combine Raman and reflectance anisotropy spectroscopy (RAS) with first-principles calculations in the framework of the density functional theory. RAS suggests a weakly isotropic surface, and Raman spectroscopy reveals the presence of surface localized phonons. Atomistic calculations allow to assign the detected Raman peaks to phonon modes localized at the silicide layer. The good agreement between the calculations and the measurements provides a strong argument for the employed structural model.

Density-functional theory is used to explore the Si(553)-Au surface dynamics. Our study (i) reveals a complex two-stage order-disorder phase transition where with rising temperature first the ×3 order along the Si step edges and, subsequently, the ×2 order of the Au chains is lost, (ii) identifies the transient modification of the electron chemical potential during soft Au chain vibrations as instrumental for disorder at the step edge, and (iii) shows that the transition leads to a self-doping of the Si dangling-bond wire at the step edge. The calculations are corroborated by Raman measurements of surface phonon modes and explain previous electron diffraction, scanning tunneling microscopy, and surface transport data.

We propose a quantitative and reversible method for tuning the charge localization of Au-stabilized stepped Si surfaces by site-specific hydrogenation. This is demonstrated for Si(553)-Au as a model system by combining density functional theory simulations and reflectance anisotropy spectroscopy experiments. We find that controlled H passivation is a two-step process: step-edge adsorption drives excess charge into the conducting metal chain "reservoir" and renders it insulating, while surplus H recovers metallic behavior. Our approach illustrates a route towards microscopic manipulation of the local surface charge distribution and establishes a reversible switch of site-specific chemical reactivity and magnetic properties on vicinal surfaces.

In this work, the microfluidic-assisted synthesis of copper-tetracyanoquinodimethane (Cu-TCNQ) nanostructures in an ambient environment is reported for the first time. A two-layer microfluidic device comprising parallel actuated microchambers was used for the synthesis and enabled excellent fluid handling for the continuous and multiple chemical reactions in confined ultrasmall chambers. Different precautions were applied to ensure the reduction state of copper (Cu) for the synthesis of Cu-TCNQ charge-transfer compounds. The localized synthesis of Cu and in situ transformation to Cu-TCNQ complexes in solution were achieved by applying different gas pressures in the control layer. Additionally, various diameters of the Cu-TCNQ nano/microstructures were obtained by adjusting the concentration of the precursors and reaction time. After the synthesis, platinum (Pt) microelectrode arrays, which were aligned at the microchambers, could enable the in situ measurements of the electronic properties of the synthesized nanostructures without further manipulation. The as-prepared Cu-TCNQ wire bundles showed good conductivity and a reversible hysteretic switching effect, which proved the possibility in using them to build advanced nanoelectronics.

The Si(111)-5×2-Au surface is increasingly of interest because it is one of the rare atomic chain systems with quasi-one-dimensional properties. For the deposition of 0.7 monolayers of Au, these chains are metallic. Upon the evaporation of an additional submonolayer amount of gold, the surface becomes insulating but keeps the 5×2 symmetry. This metal-to-insulator transition was in situ monitored based on the infrared plasmonic signal change with coverage. The phase transition is theoretically explained by total-energy and band-structure calculations. Accordingly, it can be understood in terms of the occupation of the originally half-filled one-dimensional band at the Fermi level. By annealing the system, the additional gold is removed from the surface and the plasmonic signal is recovered, which underlines the stability of the metallic structure. So, recent results on the infrared plasmonic signals of the Si(111)-5 × 2-Au surface are supported. The understanding of potential one-dimensional electrical interconnects is improved.

We report on the generation of photocurrent in the visible and ultraviolet range from planar devices built from the Ge nanocrystals grown on a heavy n-doped Si(001) substrate covered with 5 nm thick thermally grown SiO2. These Ge nanostructures/SiO2/n(+)-Si devices are shown to generate photocurrent with an Incident-Photon-to-electron Conversion Efficiency (IPCE) spectral range depending on the Ge nanocrystals size. The increase of the IPCE value of our devices in the 350-600 nm range correlates well with the absorbance of Ge.

This 42-year-old male patient voluntarily discontinued treatment for lung TBC and twenty days later developed acute paraplegia. Magnetic resonance imaging (MRI) demonstrated a large intramedullary cavity extending from T2 to the conus medullaris. Having resumed anti-TBC treatment, the patient progressed favourably, despite any change in cavity size. Tuberculous meningitis may be complicated by the appearance of intramedullary cavities by two distinct mechanisms: 1) adhesive arachnoiditis at the skull base with obstruction of Luschka and Magendie foramina, followed by hydrocephalus and hydromyelia; and 2) spinal cord arachnoiditis with the development of arachnoidal and intramedullary cysts. In either case, symptoms are of late presentation. To the best of our knowledge, this is the first report in the literature of lung tuberculosis associated with syringomyelia but without basal arachnoiditis. Acute clinical presentation with paraplegia is exceptional.

Colorectal cancer (CRC) cells display remarkable adaptability, orchestrating metabolic changes that confer growth advantages, pro-tumor microenvironment, and therapeutic resistance. One such metabolic change occurs in glutamine metabolism. Colorectal tumors with high glutaminase (GLS) expression exhibited reduced T cell infiltration and cytotoxicity, leading to poor clinical outcomes. However, depletion of GLS in CRC cells has minimal effect on tumor growth in immunocompromised mice. By contrast, remarkable inhibition of tumor growth is observed in immunocompetent mice when GLS is knocked down. It is found that GLS knockdown in CRC cells enhanced the cytotoxicity of tumor-specific T cells. Furthermore, the single-cell flux estimation analysis (scFEA) of glutamine metabolism revealed that glutamate-to-glutathione (Glu-GSH) flux, downstream of GLS, rather than Glu-to-2-oxoglutarate flux plays a key role in regulating the immune response of CRC cells in the tumor. Mechanistically, inhibition of the Glu-GSH flux activated reactive oxygen species (ROS)-related signaling pathways in tumor cells, thereby increasing the tumor immunogenicity by promoting the activity of the immunoproteasome. The combinatorial therapy of Glu-GSH flux inhibitor and anti-PD-1 antibody exhibited a superior tumor growth inhibitory effect compared to either monotherapy. Taken together, the study provides the first evidence pointing to Glu-GSH flux as a potential therapeutic target for CRC immunotherapy., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Active optical control over matter is desirable in many scientific disciplines, with prominent examples in all-optical magnetic switching 1,2 , light-induced metastable or exotic phases of solids 3-8 and the coherent control of chemical reactions 9,10 . Typically, these approaches dynamically steer a system towards states or reaction products far from equilibrium. In solids, metal-to-insulator transitions are an important target for optical manipulation, offering ultrafast changes of the electronic 4 and lattice 11-16 properties. The impact of coherences on the efficiencies and thresholds of such transitions, however, remains a largely open subject. Here, we demonstrate coherent control over a metal-insulator structural phase transition in a quasi-one-dimensional solid-state surface system. A femtosecond double-pulse excitation scheme 17-20 is used to switch the system from the insulating to a metastable metallic state, and the corresponding structural changes are monitored by ultrafast low-energy electron diffraction 21,22 . To govern the transition, we harness vibrational coherence in key structural modes connecting both phases, and observe delay-dependent oscillations in the double-pulse switching efficiency. Mode-selective coherent control of solids and surfaces could open new routes to switching chemical and physical functionalities, enabled by metastable and non-equilibrium states.

Lung cancer is the second most prevalent cancer and the leading cause of cancer-related death worldwide. Surgery, chemotherapy, molecular targeted therapy, immunotherapy, and radiotherapy are currently available as treatment methods. However, drug resistance is a significant factor in the failure of lung cancer treatments. Novel therapeutics have been exploited to address complicated resistance mechanisms of lung cancer and the advancement of nanomedicine is extremely promising in terms of overcoming drug resistance. Nanomedicine equipped with multifunctional and tunable physiochemical properties in alignment with tumor genetic profiles can achieve precise, safe, and effective treatment while minimizing or eradicating drug resistance in cancer. Here, this work reviews the discovered resistance mechanisms for lung cancer chemotherapy, molecular targeted therapy, immunotherapy, and radiotherapy, and outlines novel strategies for the development of nanomedicine against drug resistance. This work focuses on engineering design, customized delivery, current challenges, and clinical translation of nanomedicine in the application of resistant lung cancer., (© 2023 Wiley-VCH GmbH.)

The advance of immunotherapy has shifted the paradigm of cancer management in clinics. Nevertheless, a considerable subset of pancreatic ductal adenocarcinoma (PDAC) patients marginally respond to current immunotherapy due to the occurrence of dynamic immune evasion arising from intrinsic and therapeutic stress. In this investigation, the pivotal role of pancreatic cancer-associated fibroblast (CAF)-induced fibrosis and tumor cell-mediated T-cell exhaustion in driving the dynamic immune evasion is identified. Building upon this discovery, the authors herein engineer a novel peptide-drug conjugate (PDC)-based self-adaptive nanoregulator for mitigating dynamic immune evasion of PDAC. The resulting nanoregulator can perform a two-stage morphology transformation from spherical micelle to nanofiber, and subsequently from nanofiber to spherical nanoparticles. Such kind of nanostructure design can facilitate differentialized delivery of CAF inhibitor in the extracellular matrix for intervening CAF-mediated tumor fibrosis, and indoleamine 2,3-dioxygenase 1 inhibitor to tumor cells for relieving IDO1-kynurenine axis-induced T-cell exhaustion. Antitumor study with the self-adaptive nanoregulator elicited persistent antitumor immunity and remarkable antitumor performance in both Panc02 and KPC tumor models in vivo. Taken together, the PDC-based self-adaptive nanoregulator may provide a novel avenue for enhanced PDAC immunotherapy., (© 2023 Wiley-VCH GmbH.)

Culturally inherited institutional norms structure much of human social life. Successfully replicating institutions train their current members to behave in the generally adaptive ways that served past members. Ancestor veneration is a well-known manifestation of this phenomenon whereby deference is conferred to prestigious past members who are used as cultural models. Such norms of respect may be maintained by punishment based on evidence from theory and laboratory experiments, but there is little observational evidence to show that punishment is commonly used. To test for punishment as a mechanism that maintains these norms, we examine a norm of ancestor veneration in a natural field experiment at the Memorial Student Center (MSC) at Texas A&M University. The MSC is a memorial to university war dead, and the expectation is that all who enter the building remove their hats out of respect. Observations reveal that hat removal is significantly more common at the MSC than at two control locations. Survey data indicate that most, but not all, subjects understand the norm to be veneration of the dead, and most expect others to follow the norm. Many report a strong negative emotional response when asked to imagine the norm being violated. Sixty-two percent report they would definitely or probably ask the noncompliant to uncover. Focal follow data show that punishment is relatively rare, however, with the majority of behatted subjects going unreproached as they pass through the building. Both survey and observational data indicate there is a motivated minority that enthusiastically enforces the norm., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Magnetic hyperthermia (MH) harnesses the heat-releasing properties of superparamagnetic iron oxide nanoparticles (SPIONs) and has potential to stimulate immune activation in the tumor microenvironment whilst sparing surrounding normal tissues. To assess feasibility of localized MH in vivo, SPIONs are injected intratumorally and their fate tracked by Zirconium-89-positron emission tomography, histological analysis, and electron microscopy. Experiments show that an average of 49% (21-87%, n = 9) of SPIONs are retained within the tumor or immediately surrounding tissue. In situ heating is subsequently generated by exposure to an externally applied alternating magnetic field and monitored by thermal imaging. Tissue response to hyperthermia, measured by immunohistochemical image analysis, reveals specific and localized heat-shock protein expression following treatment. Tumor growth inhibition is also observed. To evaluate the potential effects of MH on the immune landscape, flow cytometry is used to characterize immune cells from excised tumors and draining lymph nodes. Results show an influx of activated cytotoxic T cells, alongside an increase in proliferating regulatory T cells, following treatment. Complementary changes are found in draining lymph nodes. In conclusion, results indicate that biologically reactive MH is achievable in vivo and can generate localized changes consistent with an anti-tumor immune response., (© 2021 The Authors. Small published by Wiley-VCH GmbH.)