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Engagement in behaviors of concern (BoCs) by adults with intellectual and developmental disabilities (IDDs) living in small residential group homes can negatively impact the health, safety, and quality of life of the individuals themselves and others living and working in the home. Little is known about the societal cost of BoCs. The objective of this study was to quantify the cost of BoCs for residents, residential group homes, and public and healthcare services in terms of different behaviors. This descriptive study used incident and monthly behavior-tracking reports collected from small residential group homes for six months prior to implementing a social problem-solving intervention aimed at decreasing BoCs. The mean cost per BoC incident per resident was USD 80 ± 601. Health and safety incidents had the highest cost, followed by begging. BoCs impose costs on small residential group homes, public and healthcare services, and residents themselves.

The main proteases M pro are a group of highly conserved cysteine hydrolases in β-coronaviruses. They have been demonstrated to play an unavoidable role in viral replication, and consequently they have been suggested as key targets for treating coronavirus-caused infectious diseases, mainly from the COVID-19 epidemic. Since the most functional form for M pro enzymatic activity is associated to its homodimer, compounds inhibiting dimerization should also inhibit catalytic activity. We show how PIR-SEIRA (Plasmonic Internal Reflection-Surface Enhanced InfraRed Absorption) spectroscopy can be a noteworthy technique to study proteins subtle structural variations associated to inhibitor binding. Nanoantennas arrays can selectively confine and enhance electromagnetic field via localized plasmonic resonances, thus promoting ultrasensitive detection of biomolecules in close proximity of nanoantenna arrays and enabling the effective investigation of protein monolayers. By adopting this approach, reflection measurements conducted under back illumination of nanoantennas allow to probe anchored protein monolayers, with minimum contribution of environmental buffer molecules. PIR-SEIRA spectroscopy on M pro was carried out by ad hoc designed devices, resonating in the spectral region of Amide I and Amide II bands. We evaluated here the structure of anchored monomers and dimers in different buffered environment and in presence of a newly designed M pro inhibitor. Experimental results show that dimerization is not associated to relevant backbone rearrangements of the protein at secondary structure level, and even if the compound inhibits the dimerization, it is not effective at breaking preformed dimers., Competing Interests: Declaration of competing interest The authors 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.)

Aim: The microenvironment effect on the tumoral-derived Extracellular Vesicle release, which is of significant interest for biomedical applications, still represents a rather unexplored field. The aim of the present work is to investigate the interrelation between extracellular matrix (ECM) stiffness and the release of small EVs from cancer cells. Here, we focus on the interrelation between the ECM and small extracellular vesicles (sEVs), specifically investigating the unexplored aspect of the influence of ECM stiffness on the release of sEVs., Methods: We used a well-studied metastatic Triple-Negative Breast Cancer (TNBC) cell line, MDA-MB-231, as a model to study the release of sEVs by cells cultured on substrates of different stiffness. We have grown MDA-MB-231 cells on two collagen-coated polydimethylsiloxane (PDMS) substrates at different stiffness (0.2 and 3.6 MPa), comparing them with a hard glass substrate as control, and then we isolated the respective sEVs by differential ultracentrifugation. After checking the cell growth conditions [vitality, morphology by immunofluorescence microscopy, stiffness by atomic force microscopy (AFM)], we took advantage of a multi-parametric approach based on complementary techniques (AFM, Nanoparticle Tracking Analysis, and asymmetric flow field flow fractionation with a multi-angle light scattering detector) to characterize the TNBC-derived sEV obtained in the different substrate conditions., Results: We observe that soft substrates induce TNBC cell softening and rounding. This effect promotes the release of a high number of larger sEVs., Conclusion: Here, we show the role of ECM physical properties in the regulation of sEV release in a TNBC model. While the molecular mechanisms regulating this effect need further investigation, our report represents a step toward an improved understanding of ECM-cell-sEVs crosstalk., Competing Interests: All authors declared that there are no conflicts of interest., (© The Author(s) 2024.)

Missense mutations in EGFR's catalytic domain alter its function, promoting cancer. SEIRA spectroscopy, supported by MD simulations, reveals structural differences in the compactness and hydration of helical motifs between active and inactive EGFR conformations models. These findings provide novel insights into the biophysical mechanisms driving EGFR activation and drug resistance, offering a robust method for studying emerging EGFR mutations and their structural impacts on TKIs' efficacy.

Water under soft nanoconfinement features physical and chemical properties fundamentally different from bulk water; yet, the multitude and specificity of confining systems and geometries mask any of its potentially universal traits. Here, we advance in this quest by resorting to lipidic mesophases as an ideal nanoconfinement system, allowing inspecting the behavior of water under systematic changes in the topological and geometrical properties of the confining medium, without altering the chemical nature of the interfaces. By combining Terahertz absorption spectroscopy experiments and molecular dynamics simulations, we unveil the presence of universal laws governing the physics of nanoconfined water, recapitulating the data collected at varying levels of hydration and nanoconfinement topologies. This geometry-independent universality is evidenced by the existence of master curves characterizing both the structure and dynamics of simulated water as a function of the distance from the lipid-water interface. Based on our theoretical findings, we predict a parameter-free law describing the amount of interfacial water against the structural dimension of the system (i.e., the lattice parameter), which captures both the experimental and numerical results within the same curve, without any fitting. Our results offer insight into the fundamental physics of water under soft nanoconfinement and provide a practical tool for accurately estimating the amount of nonbulk water based on structural experimental data.

The cellular response to cisplatin was assessed in human osteosarcoma cells, using synchrotron-based (SR) Fourier Transform InfraRed nanospectroscopy (nano-FTIR) at the MIRIAM beamline B22 of Diamond Light Source (UK). This label-free mapping method delivered simultaneous morphological and biochemical information on a subcellular level (i.e. 100 s nanometer or better). Based on specific spectral biomarkers, the main biochemical constituents affected by the drug were identified at distinct locations within the cell´s inner body. Cisplatin was shown to have a noteworthy effect on proteins, mostly within the cytoplasm. A clear drug impact on cellular lipids was also observed. Within current literature on s-SNOM, this nanospectroscopy work represents a first successful application in life sciences providing full fingerprint nano-FTIR spectra across intact human cancer cells., (© 2024. The Author(s).)

This study compares the impact of two isolation methods, ultracentrifugation (UC) and size exclusion chromatography (SEC), on small extracellular vesicles (sEVs) from primary human cardiac mesenchymal-derived progenitor cells (CPCs). sEV_UC and sEV_SEC exhibit similar size, marker expression, and miRNA cargo, but sEV_UC contains notably higher total protein levels. In vitro assays show that sEV_UC, despite an equal particle count, induces more robust ERK phosphorylation, cytoprotection, and proliferation in iPS-derived cardiomyocytes (iPS-CMs) compared to sEV_SEC. sEV_UC also contains elevated periostin (POSTN) protein levels, resulting in enhanced focal adhesion kinase (FAK) phosphorylation in iPS-CMs. Importantly, this effect persists with treatment with soluble free-sEV protein fraction from SEC (Prote_SEC), indicating that free proteins like POSTN in sEV_UC enhance FAK phosphorylation. In vivo, sEV contamination with soluble proteins doesn't affect cardiac targeting or FAK phosphorylation, underscoring the intrinsic tissue targeting properties of sEV. These findings emphasize the need for standardized sEV isolation methods, as the choice of method can impact experimental outcomes, particularly in vitro., (© 2023 Wiley-VCH GmbH.)

The manipulation of carbon nitride (CN) structures is one main avenue to enhance the activity of CN-based photocatalysts. Increasing the efficiency of photocatalytic heterogeneous materials is a critical step toward the realistic implementation of sustainable schemes for organic synthesis. However, limited knowledge of the structure/activity relationship in relation to subtle structural variations prevents a fully rational design of new photocatalytic materials, limiting practical applications. Here, the CN structure is engineered by means of a microwave treatment, and the structure of the material is shaped around its suitable functionality for Ni dual photocatalysis, with a resulting boosting of the reaction efficiency toward many CX (X = N, S, O) couplings. The combination of advanced characterization techniques and first-principle simulations reveals that this enhanced reactivity is due to the formation of carbon vacancies that evolve into triazole and imine N species able to suitably bind Ni complexes and harness highly efficient dual catalysis. The cost-effective microwave treatment proposed here appears as a versatile and sustainable approach to the design of CN-based photocatalysts for a wide range of industrially relevant organic synthetic reactions., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Abstract: This educational innovation describes the implementation and evaluation of a telehealth maternal-newborn home visit clinical experience for nurse practitioner students at an urban, private research university in the Midwest. The visits were conducted using the Family Connects evidence-based universal support program for families with newborns to evaluate each family's unique risks and to align their needs with available community resources. Students were prepared for the clinical experience through advanced practice didactic modules and simulation and then participated in the visits over a 2-week period. After the clinical opportunity, both students and community health nurse collaborators completed a survey about their experiences. The students reported feeling prepared to participate in the visits, that they were able to meet clinical objectives using telehealth, and learned about the community resources available for families with newborns. The nurses reported feeling prepared to collaborate with nurse practitioner students and that they benefitted from having a student participate in the visits. The experience prepared the students to meet the needs of a diverse patient population during the early postpartum/newborn period by providing newborn care advice, addressing access to health, assessing social determinants of health, and considering community resource referrals to reduce disparities and improve health equity. This article describes how a telehealth clinical experience addresses the American Association of Colleges of Nursing Essentials for advanced-level nursing students and provides recommendations for incorporating and evaluating telehealth clinical experiences in pediatric advanced practice education., Competing Interests: Competing interests: The authors report no conflicts of interest., (Copyright © 2022 American Association of Nurse Practitioners.)

Herein, we report on a smart biosensing platform that exploits gold nanoparticles (AuNPs) functionalized through ssDNA self-assembled monolayers (SAM) and the DNA-directed immobilization (DDI) of DNA-protein conjugates; a novel, high-sensitivity optical characterization technique based on a miniaturized gel electrophoresis chip integrated with online thermal lens spectrometry (MGEC-TLS), for the high-sensitivity detection of antigen binding events. Specifically, we characterized the physicochemical properties of 20 nm AuNPs covered with mixed SAMs of thiolated single-stranded DNA and bio-repellent molecules, referred to as top-terminated oligo-ethylene glycol (TOEG6), demonstrating high colloidal stability, optimal binder surface density, and proper hybridization capacity. Further, to explore the design in the frame of cancer-associated antigen detection, complementary ssDNA fragments conjugated with a nanobody, called C8, were loaded on the particles and employed to detect the presence of the HER2-ECD antigen in liquid. At variance with conventional surface plasmon resonance detection, MGEC-TLS characterization confirmed the capability of the assay to titrate the HER2-ECD antigen down to concentrations of 440 ng/mL. The high versatility of the directed protein-DNA conjugates immobilization through DNA hybridization on plasmonic scaffolds and coupled with the high sensitivity of the MGEC-TLS detection qualifies the proposed assay as a potential, easily operated biosensing strategy for the fast and label-free detection of disease-relevant antigens., Competing Interests: The authors declare no conflict of interest.

Background: Compassion fatigue (CF) and burnout are well described phenomena among oncology nurses. Physical activity (PA) has been shown to reduce CF and burnout., Objectives: The purpose of this pilot study was to determine the feasibility of promoting PA and assessing its impact on CF and burnout among RNs across three ambulatory care cancer clinics., Methods: A convenience sample of nurses with varying roles were invited to participate. Feasibility was assessed by participant accrual and retention rates. CF and burnout were assessed at weeks 0, 6, and 12. The Yale Physical Activity Survey was used to obtain self-reported PA, and daily steps were tracked using participants' personal devices., Findings: Stress scores decreased. Burnout scores demonstrated levels of low emotional exhaustion, moderate depersonalization, and moderate to high personal achievement. Leisurely walking increased significantly, and average daily step counts increased by 37% for weekdays, 10% for weekend days, and 29% for the total week.

Background: The COVID-19 pandemic has highlighted the importance of a strong, effective public health nursing workforce while also requiring public health nursing faculty to adapt teaching strategies as courses transitioned online. It is essential to understand how the pandemic-enforced transition from face-to-face to remote learning impacts student outcomes. The purpose of this paper is to compare student learning outcomes in a pre-licensure public health nursing course before, during, and after the transition to remote learning., Methods: Descriptive statistics were computed for assignments, exams, and final course grades for three terms (Fall 2019, Spring 2020 and Fall 2020)., Results: Analysis showed statistically significant differences between terms for assignments and exams but not the final course grade. However, these differences were driven by small standard deviations rather than differences between mean scores demonstrating that there was actual little difference in student learning outcomes across terms., Conclusions: Authors suggest strategies to support consistent academic outcomes and future research needed understand student learning outcomes during the pandemic; ultimately building the public health nursing workforce necessary to address the current and future public health crises., (© 2021 Wiley Periodicals LLC.)

Aim and Objectives: To explore and understand the current practice, perceptions, and knowledge of general surgery trainees, advanced practice providers, and surgical nurses regarding opioid prescribing and administration. To this end, a novel opioid education and training was introduced to educate these practitioners on safe opioid practices in surgical patients., Background: National awareness of the opioid epidemic has increased significantly in the last several years. However, there remain a disturbingly high number of opioid prescriptions written in the US indicating a need for improved provider and nurse education. This involves increasing awareness and understanding of national guidelines as well as implementing multi-modal therapy to treat pain., Design: Pre-post-intervention quality improvement project., Methods: An opioid education and training involving a morphine equivalent daily dosing calculator in the electronic medical record was provided to 26 surgical trainees, eight advanced practice providers and 97 surgical nurses in November 2019. Perceptions, current practice and knowledge were measured using a pre- and post-intervention survey (SQUIRE checklist)., Results: The survey results showed a positive clinical change in perception of opioid use in surgical patients following the intervention and a modest decrease in the average morphine equivalent daily dosing at discharge in general and transplant surgery patients., Conclusions: Effective pain management for surgical patients must be individualised. Safe opioid prescribing should involve an interdisciplinary approach with all members of the team undergoing assessment of their opioid knowledge and prescribing habits, easily accessible training tools and opioid calculators in the electronic medical record., Relevance to Clinical Practice: Our initiative may provide useful information to settings that replicate use of a morphine equivalent daily dosing calculator in the electronic medical record. Utilisation of safe opioid prescribing tools in the electronic medical record and continuing education for providers and nurses can help ensure the safety of surgical patients., (© 2020 John Wiley & Sons Ltd.)

Monoclonal antibody-based immunotherapy is one of the pillars of cancer treatment. However, for an efficient and personalized approach to the therapy, a quantitative evaluation of the right dose for each patient is required. In this study, we developed a simple, label-free, and rapid approach to quantify Trastuzumab, a humanized IgG1 monoclonal antibody used against human epidermal growth factor receptor 2 (HER2), overexpressed in breast cancer patients, based on localized surface plasmon resonance (LSPR). The central idea of this work was to use gold nanoparticles (AuNPs) as plasmonic scaffolds, decorated with HER2 binders mixed with oligo-ethylene glycol (OEG) molecules, to tune the surface density of the attached macromolecules and to minimize nonspecific binding events. Specifically, we characterized and optimized a self-assembled monolayer of mixed alkylthiols terminated with nitrilotriacetic acid (NTA), and OEG3 as a spacing ligand to achieve both excellent dispersibility and high reliability in protein immobilization. The successful immobilization of histidine-tagged HER2 (His-tagged HER2) on NTA via cobalt (II) chelates was demonstrated, confirming the fully functional attachment of the proteins to the AuNP surface. The proposed design demonstrates the capability of producing a clear readout that enables the transduction of a Trastuzumab/HER2 binding event into optical signals based on the wavelength shifts in LSPR, which allowed for detecting clinically relevant concentrations of Trastuzumab down to 300 ng/mL in the buffer and 2 µg/mL in the diluted serum. This strategy was found to be fast and highly specific to Trastuzumab. These findings make the present platform an auspicious tool for developing affordable bio-nanosensors.

Trimethylamine N-oxide (TMAO) is a well known osmolyte in nature, which is used by deep sea fish to stabilize proteins against High Hydrostatic Pressure (HHP). We present a combined ab initio molecular dynamics, force field molecular dynamics, and THz absorption study of TMAO in water up to 12 kbar to decipher its solvation properties upon extreme compression. On the hydrophilic oxygen side of TMAO, AIMD simulations at 1 bar and 10 kbar predict a change of the coordination number from a dominating TMAO·(H 2 O) 3 complex at ambient conditions towards an increased population of a TMAO·(H 2 O) 4 complex at HHP conditions. This increase of the TMAO-oxygen coordination number goes in line with a weakening of the local hydrogen bond network, spectroscopic shifts and intensity changes of the corresponding intermolecular THz bands. Using a pressure-dependent HHP force field, FFMD simulations predict a significant increase of hydrophobic hydration from 1 bar up to 4-5 kbar, which levels off at higher pressures up to 10 kbar. THz spectroscopic data reveal two important pressure regimes with spectroscopic inflection points of the dominant intermolecular modes: The first regime (1.5-2 kbar) is barely recognizable in the simulation data. However, it relates well with the observation that the apparent molar volume of solvated TMAO is nearly constant in the biologically relevant pressure range up to 1 kbar as found in the deepest habitats on Earth in the ocean. The second inflection point around 4-5 kbar is related to the amount of hydrophobic hydration as predicted by the FFMD simulations. In particular, the blueshift of the intramolecular CNC bending mode of TMAO at about 390 cm -1 is the spectroscopic signature of increasingly pronounced pressure-induced changes in the solvation shell of TMAO. Thus, the CNC bend can serve as local pressure sensor in the multi-kbar pressure regime.

Introduction: The purpose of this project was to identify barriers to the use of pain prevention techniques during immunization., Method: A national, voluntary survey was distributed to members of the National Association of Pediatric Nurse Practitioners in June 2019., Results: The survey gathered information about the type of practitioner (pediatric nurse practitioner, family nurse practitioner, nurse, etc.), practice location (inpatient, primary care, specialty care, etc.), and patient population served and also included information regarding geographic location, socioeconomic status, insurance coverage, and immunization status as well as current practice information. Respondents identified the following barriers: time (22.4%), availability (17.5%), lack of knowledge (17%), staff support (14.1%), cost (12.1%), lack of resources (7.4%), safety concerns (4.7%), environmental factor (3.4%), and other (1.4%)., Discussion: The lack of pain prevention techniques is primarily because of availability, lack of knowledge and staff support, and cost. Proposed means to address these barriers include the development of a toolkit., (Copyright © 2021 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.)

Burnout decreases work performance and quality of care and can result in medical errors, lower patient satisfaction, and higher rates of turnover. A study of 68 000 registered nurses showed that 35% of hospital nurses were experiencing symptoms of burnout. A systematic review identified that mindfulness-based interventions for health care professionals reduced stress and burnout and increased self-compassion and general health. However, the authors determined that more high-quality research is needed. This study examined the impact of a 4-hour workshop on burnout syndrome, perceived stress, and mindfulness skills. The objective of this study was to determine whether a 4-hour mindfulness workshop was effective in reducing burnout and perceived levels of stress and increasing mindfulness. Nurses at a Midwest academic medical center were recruited through e-mail to attend a 4-hour mindfulness workshop. Participants completed the Maslach Burnout Inventory-Human Service Survey, Perceived Stress Scale, and Cognitive and Affective Mindfulness Scale-Revised prior to the start of the workshop and 1 and 6 months after the workshop. The study design allowed for comparisons preintervention and postintervention. Of the 52 nurses who completed the baseline questionnaires, 94% were female with an average age of 38 years. Thirty-one percent completed the questionnaires at 1 month and 20 nurses at 6 months. At 1 month, nurses reported statistically significant decreased perceptions of stress (-2.31, P = .01) and emotional exhaustion (-4.78, P = .03). Mindfulness skills, personal accomplishment, and depersonalization improved but were not statistically significant. At 6 months, statistically significant findings included increased perceptions of mindfulness (2.50, P = .04), personal accomplishment (4.43, P = .04), and decreased emotional exhaustion (-6.21, P = .05). Perceptions of stress and depersonalization improved but were not statistically significant. In this study, nurses reported decreases in burnout and perceived stress and increases in mindfulness after attending a 4-hour mindfulness workshop. Further research is needed to determine the long-term impact of mindfulness-based training on nurses' burnout, stress, and mindfulness skills. The results of this study add to the body of literature that supports the benefits of mindfulness-based interventions., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: The purpose of this study was to assess nurses' knowledge, perceived self-efficacy, and intended behaviors relative to integrating the social determinants of health (SDoH) into clinical practice., Design and Methods: A cross-sectional study was completed with 768 nurses working in three hospitals within a large regional healthcare system located in the Midwest. Data were collected using an adapted 71-item SDoH Survey, which measured nurses' confidence in and frequency of discussing the SDoH with patients, general knowledge of the SDoH, familiarity with patients' social and economic conditions, and awareness of their institution's health equity strategic plan to achieve health equity. The institution's health equity strategic plan reflects the organization's commitment to improving the health of individuals and neighborhoods by addressing the SDoH known to influence health status and life expectancy. Finally, participants were asked to describe barriers to incorporating the SDoH into practice along with completing five demographic items. Descriptive statistics were used to describe the findings., Findings: Of the 768 respondents, 63% had a baccalaureate degree in nursing and 33.1% reported more than 20 years in nursing. Fifty percent of respondents reported feeling more knowledgeable or confident in their ability to discuss access to care issues with patients compared to the other SDoH. Identified barriers to discussing the SDoH included insufficient time to address identified needs and unfamiliarity with internal and external resources. Respondents stressed the need for interdisciplinary education and collaboration along with more information on the role of social workers., Conclusions: Nurses are more confident in discussing certain determinants of health and could benefit from more skill development in discussing SDoH issues and stronger collaborative partnerships to address identified needs., Clinical Relevance: Findings from the study have implications for supporting the educational and resource needs of front-line nurses employed in hospitals and health systems seeking to address broader societal issues influencing the health status and outcomes of patients and communities., (© 2020 Sigma Theta Tau International.)

Objectives: As part of an improvement program targeting ICU, a national collaborative was launched to help hospitals implement patient- and family-centered care engagement initiatives., Design: Ten-month quality improvement collaborative., Setting: Guided by a national patient and family advisory group, participating teams implemented an individual project including open visitation; integrating families on rounds; establishing a patient and family advisory committee; using patient and family diaries, among others., Subjects: Sixty-three adult and PICU teams from both academic and community hospitals in 34 states participated., Interventions: Monthly team calls, quarterly webinars, newsletters, an online eCommunity, and team reporting assignments were used to facilitate project implementation., Measurements and Main Results: The Family Satisfaction with Care in the ICU 24 was used to assess family satisfaction. Clinician perceptions were assessed with the Institute for Patient- and Family-Centered Care Self-Assessment Inventory. Thematic analysis was used to explore narrative data captured from team reports of project barriers, facilitators, and the experience of participating in the collaborative. A total of 2,530 family member and 3,999 clinician surveys were completed. Postimplementation, family members reported statistically significant increases in overall family satisfaction, satisfaction with decision-making, and satisfaction with quality of care (Family Satisfaction with Care in the ICU mean score change range 0.83-1.24; p ≤ 0.027). Clinicians reported that opportunities for families to participate as members of the care team increased. Major barriers included lack of buy-in and ability to promote change in the clinical setting, managing the workload of implementation, and funding to support initiatives., Conclusions: A national collaborative format was useful to assist ICU teams to implement patient- and family-engagement initiatives. Enlisting stakeholder support, engaging unit-based champions, and highlighting benefits of family engagement can help ICU teams to promote family member involvement and engagement.

We present results of the measurement of the low frequency spectrum of solvated urea. The study revealed a blue shift of the intramolecular mode of urea centered at 150 cm -1 of Δν= 17 cm -1 upon increasing the pressure up to 10 kbar. The blue shift scaled linearly with the increase in density and was attributed to a stiffening of the water-urea intermolecular potential. We deduced an increase in the number of affected water molecules from 1 to 2 up to 5-7, which corresponds to the sterical coordination number of urea. The increase in hydration number can be explained by an suppression of the NH 2 inversion and the hydrogen bond switching around the NH 2 group. Pressure induced sterical constraints are proposed to hinder the rapid switching of hydrogen bond partners and make the water around urea less bulk-like than under ambient conditions., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The investigation of aqueous solutions containing biomolecules as a function of thermodynamic parameters, such as the pressure, is crucial for understanding biological processes. Here we report the first low frequency spectra of 1.5 M aqueous glycine from ambient pressure up to 8 kbar, i.e. in the pressure range which is crucial for understanding biological processes under extreme conditions. We observe a linear pressure dependent blue shift of the specific N-C-C-O open/close mode at ∼320 cm -1 indicating an increasing compression of the solvated glycine. In contrast, the characteristic peak of the hydrogen bond hydration water network centered, at ambient conditions, at ∼184 cm -1 non-linearly blue shifts with increasing pressure, as well, but with a slower rate than the intramolecular peak. This indicates that the macroscopic liquid-solid phase transition observed above 8 kbar pressure is driven by hydrated glycine as solidification nucleus., (Copyright © 2019 Elsevier B.V. All rights reserved.)

High-precision THz (30 to 360 cm -1 ) spectra of bulk liquid water are presented from ambient conditions up to hydrostatic pressures of 10 kbar. In concert with ab initio simulations, this allows us to characterize the molecular-level changes of the H-bond network under solvent stress conditions. Both the experimental and theoretical THz spectra reveal a blue shift in the intermolecular translational mode at 180 cm -1 by 40 cm -1 at 10 kbar and a blue shift together with an intensity increase in the relaxation mode. These changes can be traced back to a pressure-induced increase of the population of so-called short H-bond double donor configurations at the expense of those with longer such intermolecular bonds. Distinct electronic polarization effects are critical to capture the characteristic intensity changes of the THz line shape function. These advances in high-pressure THz spectroscopy open the door to investigate the pressure response of solvation shells and solute-solvent couplings.

The influence of β-lactoglobulin (βLG) on the fast sub-picosecond collective hydration dynamics in the solvent was investigated by THz absorption spectroscopy as a function of pH. It is well-known that a change in pH from pH 6 to pH 8 reversibly opens or closes the binding cavity by a transition of the E-F loop. Furthermore, the aggregation of the protein into dimers is affected, which is thought to be triggered by changes in the enzyme's electrostatic potential. Our data reveal that pH has a clear influence on the THz absorption of βLG. We discuss this influence in light of the changes observed in the sub-psec solute/solvent dynamics when probed by THz spectroscopy, which are, in turn, seen to correlate with changes in the pH value.