Pd8 Cluster: Too Small to Melt? A BOMD Study.

The question of whether a solid-liquid phase transition occurs in small clusters poses a fundamental challenge. In this study, we attempt to elucidate this phenomenon through a thorough examination of the thermal behavior and structural stability of Pd8 clusters employing ab initio simulations. Initially, a systematic global search is carried out to identify the various isomers of the Pd8 cluster. This is accomplished by employing an ab initio basin-hopping algorithm and using the PBE/SDD scheme integrated in the Gaussian code. The resulting isomers are further refined through reoptimization using the deMon2k package. To ensure the structural firmness of the lowest-energy isomer, we calculated normal modes. The structural stability as a function of temperature is analyzed through the Born-Oppenheimer molecular dynamics (BOMD) approach. Multiple BOMD trajectories at distinct simulated temperatures are examined with data clustering analysis to determine cluster isomers. This analysis establishes a connection between the potential energy landscape and the simulated temperature. To address the question of cluster melting, canonical parallel-tempering BOMD runs are performed and analyzed with the multiple-histogram method. A broad maximum in the heat capacity curve indicates a melting transition between 500 and 600 K. To further examine this transition, the mean-squared displacement and the pair-distance distribution function are calculated. The results of these calculations confirm the existence of a solid-liquid phase transition, as indicated by the heat capacity curve.

Ab initio study of longitudinal and transverse dynamics, including fast sound, in molten UO2 and liquid Li-Pb alloys.

The disparity between the masses of the two components in a binary liquid system can lead to the appearance of a peculiar phenomenon named "fast sound," which was identified for the first time in Li4Pb several decades ago and later observed in other Li based alloys. However, the exact characteristics and nature of this phenomenon and the reasons behind its appearance have not totally been identified yet. In this work, we analyze the longitudinal and transverse current correlation functions of UO2, Li4Pb, and Li0.17Pb0.83, as obtained from ab initio molecular dynamics simulations. We find that fast sound appears to occur in the two former systems but not in the latter. Additionally, we discuss some of the properties of the liquid mixtures that may be related to the appearance (or absence) of the phenomenon, such as the composition, the polyhedral structure of the melt, and the type of bonding in the system.

Risk factors associated with HCV co-infection amongst MSM and transgender women living with HIV in Mexico City: A case-control study.

INTRODUCTION AND OBJECTIVES: Hepatitis C virus infection (HCV) is a major cause of co-morbidity in people living with HIV (PLWHIV). The modes of HCV transmission in the local population of PLWHIV are still unclear. We conducted this study to identify risk factors for HCV transmission amongst PLWHIV in central Mexico. MATERIAL AND METHODS: We enrolled HIV/HCV co-infected cases and HIV controls receiving care in two outpatient clinics in Mexico City. Structured questionnaires were applied, covering demographics, history of percutaneous exposures, sexual behaviors, self-reported STD and recreational drug use. The statistical analysis for between-group comparisons were multivariate logistic regression models to assess the risk factors associated with HCV co-infection. We limited the final analysis to men who have sex with men (MSM) to avoid confounders potentially related to HCV acquisition in other populations. RESULTS: Three hundred and thirty-four MSM with HIV (175 with HCV co-infection and 159 without) were analysed. We did not identify percutaneous exposures as risk factors for HCV. Intravenous drug use (IVDU) occurred in two cases and one control case. Risk factors independently associated with acquiring HCV co-infection were: history of an ulcerative STD (aOR=2.65, 95%CI=1.44-4.88), a HCV positive partner (aOR=5.25, 95%CI=2.78-9.91), having practiced insertive fisting (aOR=2.62, 95%CI=1.01-6.90), and rectal administration of drugs during sex (aOR=2.46, 95%CI=1.25-4.84). CONCLUSIONS: Risky sexual behaviors and chemsex seem to be the main drivers of HIV/HCV co-infection amongst PLWHIV in Central Mexico. IVDU and percutaneous exposures have a minor role in the local HCV epidemic. These findings highlight the importance of testing for HCV in sexually active MSMs.

Structure, Energetics, and Thermal Behavior of Bimetallic Re-Pt Clusters.

Bimetallic Re-Pt is a widely used catalyst in petroleum reforming to obtain high-octane gasoline, but experimental and theoretical information of such systems at the subnanometer scale-namely, as cluster aggregates-is currently lacking. Thus, in this work, we performed a density functional theory-based global optimization study to determine the physicochemical properties of the most stable Re-Pt gas-phase clusters up to six atoms for all compositions. Our results indicate that in these putative global minima (GM) geometries, Re atoms tend to aggregate, while most Pt atoms remain separated from each other. This is even observed in Pt-rich clusters-an indication of the strength of the Re-Re and Re-Pt bonds over pure Pt-Pt ones-due to a strong, directional hybridization of the Re half-filled 5d and the nearly full Pt 5d states. We observe that doping monometallic Pt clusters even with a single Re atom increases their binding energy values and widens the bimetallic cluster highest occupied molecular orbital-lowest unoccupied molecular orbital gap. As catalysis occurs at elevated temperatures, we explore the concept of cluster fluxionality for Re-Pt minima in terms of the calculated isomer occupation probability, P(T). This allows us to quantify the abundance of GM and low-energy isomer configurations as a function of temperature. This is done at size 5 atoms due to the wide isomer observed variety. Our calculations indicate that for pure Re5, the P(T) of the GM configuration substantially decreases after 750 K. Especially, for Re4Pt1, the GM is the dominant structure up to nearly 700 K when the second-energy isomer becomes the stable one. Although no ordering changes are seen for Re3Pt2, Re2Pt3, and Re1Pt4, we do observe a structural transition-between the GM and the second isomer-for pure Pt5 above 1000 K. We expect this type of combined first-principles analysis to add to the overall, continuous understanding of the stability and energetics of ultrafine and highly-dispersed Re-Pt petroleum-reforming catalysts and the scarce available information on this particular bimetallic system.

The contribution of de novo coding mutations to autism spectrum disorder.

Whole exome sequencing has proven to be a powerful tool for understanding the genetic architecture of human disease. Here we apply it to more than 2,500 simplex families, each having a child with an autistic spectrum disorder. By comparing affected to unaffected siblings, we show that 13% of de novo missense mutations and 43% of de novo likely gene-disrupting (LGD) mutations contribute to 12% and 9% of diagnoses, respectively. Including copy number variants, coding de novo mutations contribute to about 30% of all simplex and 45% of female diagnoses. Almost all LGD mutations occur opposite wild-type alleles. LGD targets in affected females significantly overlap the targets in males of lower intelligence quotient (IQ), but neither overlaps significantly with targets in males of higher IQ. We estimate that LGD mutation in about 400 genes can contribute to the joint class of affected females and males of lower IQ, with an overlapping and similar number of genes vulnerable to contributory missense mutation. LGD targets in the joint class overlap with published targets for intellectual disability and schizophrenia, and are enriched for chromatin modifiers, FMRP-associated genes and embryonically expressed genes. Most of the significance for the latter comes from affected females.

Progressive disseminated histoplasmosis in Latin America and the Caribbean in people receiving highly active antiretroviral therapy for HIV infection: A systematic review.

Histoplasmosis is the most clinically significant mycosis in Latin America; still it has been neglected in people with human immunodeficiency virus (HIV). There is limited information about its contribution to morbidity and mortality in this population. We conducted a systematic review of scientific literature to provide an estimation of the frequency and mortality of histoplasmosis among people with HIV receiving highly active antiretroviral therapy (HAART) in Latin America, and factors associated with mortality. We searched articles in PubMed, Scopus, WHO Global health library, and Scielo using different combination of terms including "histoplasmosis" and HAART. We identified 949 articles, removed 662 duplicated; screened 287 abstracts; reviewed full text of 53 articles; and selected 15 articles that provided information on the number of patients studied, included patients receiving ART, and reported any measure of frequency estimate for qualitative synthesis. Studies were conducted in Argentina (n = 4), Brazil (n = 6), Colombia (n = 2), French Guyana and the Bahamas (=2), and Guatemala (n = 1). Heterogeneity of studies characteristics precluded any aggregated estimates. Histoplamosis was frequent in these cohort studies and mortality was high despite the use of HAART. Low CD4 counts, delayed HAART initiation and poor adherence were related to increased incidence, poor prognosis and increased mortality, respectively. Histoplasmosis may be an important contributor to mortality in people with HIV in Latin America. Diagnostic delays represent an important limitation for improving care of patients suspected to have histoplasmosis. Reducing histoplasmosis diagnostic delays and therapy initiation is needed to further decrease mortality.

CO2 adsorption on gas-phase Cu4-xPtx (x = 0-4) clusters: a DFT study.

Transition and noble metal clusters have proven to be critical novel materials, potentially offering major advantages over conventional catalysts in a range of value-added catalytic processess such as carbon dioxide transformation to methanol. In this work, a systematic computational study of CO2 adsorption on gas-phase Cu4-xPtx (x = 0-4) clusters is performed. An exhaustive potential energy surface exploration is initially performed using our recent density functional theory basin-hopping global optimization implementation. Ground-state and low-lying energy isomers are identified for Cu4-xPtx clusters. Secondly, a CO2 molecule adsorption process is analyzed on the ground-state Cu4-xPtx configurations, as a function of cluster composition. Our results show that the gas-phase linear CO2 molecule is deformed upon adsorption, with its bend angle varying from about 132° to 139°. Cu4-xPtx cluster geometries remain unchanged after CO2 adsorption, with the exception of Cu3Pt1 and Pt4 clusters. For these particular cases, a structural conversion between the ground-state geometry and the corresponding first isomer configurations is found to be assisted by the CO2 adsorption. For all clusters, the energy barriers between the ground-state and first isomer structures are explored. Our calculated CO2 adsorption energies are found to be larger for Pt-rich clusters, exhibiting a volcano-type plot. The overall effect of a hybrid functional including dispersion forces is also discussed.

Orbital-free density functional theory simulation of collective dynamics coupling in liquid Sn.

The appearance of a second excitation mode in the longitudinal and transverse collective dynamics of a series of liquid metals has been observed recently, either by inelastic X-ray scattering (IXS) or by first-principles molecular dynamics (FPMD). The phenomenon's origin is still uncertain, although some theories have been used with relative success to reproduce the FPMD results as a means to find an explanation for it (e.g., mode-coupling (MC) theory in liquid zinc [B. G. del Rio and L. E. González, Phys. Rev. B 95, 224201 (2017)]). For liquid tin (l-Sn), the second excitation mode in the dynamic structure factor and longitudinal current spectrum was observed by IXS [S. Hosokawa et al., J. Phys.: Condens. Matter 25, 112101 (2013)]. By performing orbital-free density functional theory MD simulations of l-Sn, we confirm the existence of a second excitation mode in the longitudinal and transverse collective dynamics and provide a theoretical explanation based on MC theory. Moreover, we introduce a new binary term in MC theory to better capture the negative minima present in the memory functions of the collective dynamics. These results confirm that the origin of the second excitation mode exhibited by the longitudinal and transverse collective dynamics in some liquid metals involves an indirect coupling of the longitudinal and transverse modes.

Healthcare providers' knowledge and attitudes about rapid tissue donation (RTD): phase one of establishing a rapid tissue donation programme in thoracic oncology.

In preparation for the development of a rapid tissue donation (RTD) programme, we surveyed healthcare providers (HCPs) in our institution about knowledge and attitudes related to RTD with lung cancer patients. A 31-item web based survey was developed collecting data on demographics, knowledge and attitudes about RTD. The survey contained three items measuring participants' knowledge about RTD, five items assessing attitudes towards RTD recruitment and six items assessing HCPs' level of agreement with factors influencing decisions to discuss RTD. Response options were presented on a 5-point Likert scale. Ninety-one HCPs participated in the study. 66% indicated they had never heard of RTD prior to the survey, 78% rated knowledge of RTD as none or limited and 95.6% reported not having ethical or religious concerns about discussing RTD with patients. The majority were either not comfortable (17.8%) or not sure if they felt comfortable discussing RTD with cancer patients (42.2%). 56.1% indicated their knowledge of RTD would play an integral role in their decision to discuss RTD with patients. 71.4% reported concerns with RTD discussion and the emotional state of the patient. Physicians and nurses play an important role in initiating conversations about recruitment and donation to research that can ultimately influence uptake. Increasing HCP knowledge about RTD is a necessary step towards building an RTD programme. Our study provides important information about characteristics associated with low levels of knowledge and practice related to RTD where additional education and training may be warranted.

Exploring Challenging Properties of Liquid Metallic Systems through Machine Learning: Liquid La and Li4Pb Systems.

In this machine learning (ML) study, we delved into the unique properties of liquid lanthanum and the Li4Pb alloy, revealing some unexpected features and also firmly establishing some of the debated characteristics. Leveraging interatomic potentials derived from ab initio calculations, our investigation achieved a level of precision comparable to first-principles methods while at the same time entering the hydrodynamic regime. We compared the structure factors and pair distribution functions to experimental data and unearthed distinctive collective excitations with intriguing features. Liquid lanthanum unveiled two transverse collective excitation branches, each closely tied to specific peaks in the velocity autocorrelation function spectrum. Furthermore, the analysis of the generalized specific heat ratio in the hydrodynamic regime investigated with the ML molecular dynamics simulations uncovered a peculiar behavior, impossible to discern with only ab initio simulations. Liquid Li4Pb, on the other hand, challenged existing claims by showcasing a rich array of branches in its longitudinal dispersion relation, including a high-frequency LiLi mode with a nonhydrodynamic optical character that maintains a finite value as q → 0. Additionally, we conducted an in-depth analysis of various transport coefficients, expanding our understanding of these liquid metallic systems. In summary, our ML approach yielded precise results, offering new and captivating insights into the structural and dynamic aspects of these materials.

Pseudomonas aeruginosa Isolates from Water Samples of the Gulf of Mexico Show Similar Virulence Properties but Different Antibiotic Susceptibility Profiles than Clinical Isolates.

Pseudomonas aeruginosa is an opportunistic pathogen found in a wide variety of environments, including soil, water, and habitats associated with animals, humans, and plants. From a One Health perspective, which recognizes the interconnectedness of human, animal, and environmental health, it is important to study the virulence characteristics and antibiotic susceptibility of environmental bacteria. In this study, we compared the virulence properties and the antibiotic resistance profiles of seven isolates collected from the Gulf of Mexico with those of seven clinical strains of P. aeruginosa. Our results indicate that the marine and clinical isolates tested exhibit similar virulence properties; they expressed different virulence factors and were able to kill Galleria mellonella larvae, an animal model commonly used to analyze the pathogenicity of many bacteria, including P. aeruginosa. In contrast, the clinical strains showed higher antibiotic resistance than the marine isolates. Consistently, the clinical strains exhibited a higher prevalence of class 1 integron, an indicator of anthropogenic impact, compared with the marine isolates. Thus, our results indicate that the P. aeruginosa marine strains analyzed in this study, isolated from the Gulf of Mexico, have similar virulence properties, but lower antibiotic resistance, than those from hospitals.

Interactions between the AraC/XylS-like transcriptional activator InvF of Salmonella Typhimurium, the RNA polymerase alpha subunit and the chaperone SicA.

Salmonella enterica serovar Typhimurium causes gastroenteritis and systemic infections in humans. For this bacterium the expression of a type III secretion system (T3SS) and effector proteins encoded in the Salmonella pathogenicity island-1 (SPI-1), is keystone for the virulence of this bacterium. Expression of these is controlled by a regulatory cascade starting with the transcriptional regulators HilD, HilC and RtsA that induce the expression of HilA, which then activates expression of the regulator InvF, a transcriptional regulator of the AraC/XylS family. InvF needs to interact with the chaperone SicA to activate transcription of SPI-1 genes including sicA, sopB, sptP, sopE, sopE2, and STM1239. InvF very likely acts as a classical activator; however, whether InvF interacts with the RNA polymerase alpha subunit RpoA has not been determined. Results from this study confirm the interaction between InvF with SicA and reveal that both proteins interact with the RNAP alpha subunit. Thus, our study further supports that the InvF/SicA complex acts as a classical activator. Additionally, we showed for the first time an interaction between a chaperone of T3SS effectors (SicA) and the RNAP.

Feasibility trial of a Spanish-language multimedia educational intervention.

BACKGROUND: Hispanic cancer patients are underrepresented in clinical trials; research suggests lack of knowledge and language barriers contribute to low accrual. Multimedia materials offer advantages to Hispanic populations because they have high acceptability, are easy to disseminate, and can be viewed with family. PURPOSE: Hispanic cancer patients and caregivers participated in focus groups to aid in developing a Spanish-language multimedia intervention to educate Hispanic cancer patients about clinical trials. We explored the feasibility of delivering the intervention in medical oncology clinics. METHODS: A total of 35 patients were randomized to either the multimedia intervention group (n = 18) or a control group (n = 17) who were asked to read the National Cancer Institute's Spanish-language clinical trials brochure. Self-reported data on knowledge about and attitudes toward clinical trials, self-efficacy for participating in a clinical trial, intention to participate in a clinical trial if asked, and receptivity to information about a clinical trial were collected at baseline and 10 days later. RESULTS: Delivery of the multimedia presentation in oncology clinics was feasible. The intervention group had more knowledge about clinical trials at follow-up than the control group; scores for intention to participate in a clinical trial by participants in the intervention group increased from 3.8 to 4.0 of a possible 5, but declined in the control group from 4.5 to 4.1. No statistically significant difference was detected between groups in scores for attitudes or self-efficacy for making a decision to participate in a clinical trial. LIMITATIONS: Our sample size was inadequate to identify differences between the informational methods. Although all patients were asked about their willingness to participate in a clinical trial, this decision was hypothetical. In addition, the study was conducted with a sample of Spanish-speaking Hispanic cancer patients at a comprehensive cancer center in Florida. Thus, the results may not generalize to other Hispanic populations. CONCLUSION: In the pilot project, we demonstrated the feasibility of delivering multimedia information to patients in medical oncology clinics. Because delivery in a clinical setting was found to be feasible, a larger study should be conducted to evaluate the efficacy of the multimedia intervention with respect to promoting accrual of Hispanic patients to clinical trials.

Improving awareness of cancer clinical trials among Hispanic patients and families: audience segmentation decisions for a media intervention.

Clinical trials hold great promise for cancer treatment; yet, Hispanic cancer patients have low rates of clinical trial participation. Lack of awareness and knowledge of clinical trials and language barriers may account for low participation rates. Patient education through audiovisual materials can improve knowledge of and attitudes toward clinical trials among Hispanic populations. In this study, 36 Hispanic cancer patients/survivors and caregivers in Florida and Puerto Rico participated in focus groups to aid in developing a Spanish-language DVD and booklet intervention designed to increase knowledge about clinical trials. Focus group results showed (a) low levels of knowledge about clinical trials, (b) uncertainty about why a physician would expect a patient to make a choice about treatment, and (c) desire for family participation in decision making. Respondents expressed various preferences for aspects of the DVD such as showing extended family in the DVD and physician explanations about key terms. On the basis of these preferences, the authors developed a creative brief for a DVD. The content of the DVD was reviewed by Hispanic community leaders and key stakeholders. A final DVD was created, in Spanish, using Hispanic patients and physicians, which contained the information deemed important from the focus groups and stakeholder interviews. The DVD is complete with companion booklet and currently undergoing a randomized control trial.

The bottleneck effect in lung cancer clinical trials.

Clinical trials provide the most promising way to improve treatment outcomes in cancer. This study examined the rate at which eligible patients with lung cancer, at a National Cancer Institute-designated cancer center in the South, were offered a clinical trial and explored for reasons for ineligibility. We retrospectively reviewed 300 randomly selected lung cancer patients' medical records seen in 2010, to assess clinical trial offers to eligible patients, reasons for not offering an eligible patient a trial, demographic factors associated with eligibility, and reasons for refusal among those offered a trial. Of the 300 patient charts, seven were excluded for lack of confirmed lung cancer diagnosis. Forty-six of the remaining 293 (15.7%) patients were eligible for a clinical trial. Forty-five of the 46 (97.8%) were considered for a trial by their oncologist. Thirty-five of the 45 (77.8%) were offered a trial: 15 agreed (42.9% of those offered, 5.1% of patients reviewed), 11 declined, and 9 were undecided at the end of the review window. Patients with poor Eastern Cooperative Oncology Group (ECOG) performance status levels and small cell (SC) diagnoses were significantly less likely to be eligible for a trial. Results suggest that oncologists at the cancer center are effectively presenting all eligible patients with the option of a clinical trial; however, there is a need to increase the number of approved clinical trials for patients with SC or ECOG score greater than 2.

Tucatinib promotes immune activation and synergizes with programmed cell death-1 and programmed cell death-ligand 1 inhibition in HER2-positive breast cancer.

BACKGROUND: Programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) inhibitors have poor efficacy in patients with trastuzumab-resistant advanced HER2-positive breast cancer. Tucatinib is a potent, selective anti-HER2 tyrosine kinase inhibitor with proven clinical benefit in the advanced setting in patients with trastuzumab resistance. We investigated if tucatinib can alter the tumor microenvironment and if this could be harnessed for therapeutic efficacy. METHODS: We investigated the antitumor efficacy and contribution of the immune response of tucatinib using 2 immunocompetent, HER2-positive murine breast cancer models (trastuzumab-sensitive H2N113; trastuzumab-resistant Fo5) and the efficacy of tucatinib with trastuzumab and PD-1 or PD-L1 checkpoint inhibitors. RESULTS: In both models, tucatinib statistically significantly inhibited tumor growth and demonstrated dose-dependent efficacy. Ex vivo analysis by flow cytometry of tumor-infiltrating lymphocytes in mice treated with tucatinib showed increased frequency, higher proliferation, and enhanced effector function of CD8+ effector memory T cells. Tucatinib treatment also increased frequency of CD8+PD-1+ and CD8+TIM3+ T cells, CD49+ natural killer cells, monocytes, and major histocompatibility complex II expression on dendritic cells and macrophages and a decrease in myeloid-derived suppressor cells. Gene expression analysis revealed statistically significant enrichment in pathways associated with immune activation, type I and II interferon response, adaptive immune response, and antigen receptor signaling. In vivo, tucatinib and α-PD-L1 or α-PD-1 demonstrated statistically significantly increased efficacy and improved survival of mice compared with tucatinib alone. CONCLUSION: Tucatinib modulates the immune microenvironment favorably, and combination treatment with α-PD-L1 or α-PD-1 demonstrated increased efficacy in preclinical HER2-positive tumor models. These findings provide a rationale for investigation of tucatinib and immune checkpoint inhibition in the clinic.

Genomic and phenotypic characterization of Pseudomonas sp. GOM7, a novel marine bacterial species with antimicrobial activity against multidrug-resistant Staphylococcus aureus.

Antimicrobial resistance (AMR) represents a serious threat to global health. The development of new drugs to combat infections caused by bacteria resistant to multiple or even all available antibiotics is urgent. Most antibiotics used up to date have been identified from soil microorganisms. The marine environment represents an alternative source with great potential for the identification of microorganisms that produce bioactive molecules, including antibiotics. In this study, we analyzed the antibacterial activity of a collection of 82 bacterial strains isolated from marine water and sediment samples collected from the Southwestern Gulf of Mexico. Eight of the marine isolates inhibited the growth of different pathogenic bacteria, seven of which were identified as presumptive Pseudomonas aeruginosa. Interestingly, genome sequencing and phylogenetic analysis revealed that the remaining marine isolate showing antibacterial activity is a novel Pseudomonas species that we denominated Pseudomonas sp. GOM7, which was not pathogenic in the Galleria mellonella infection model in the conditions tested. Notably, Pseudomonas sp. GOM7 inhibited the growth of multidrug and methicillin-resistant strains of the priority pathogen Staphylococcus aureus. Our results show that the anti-S. aureus compound(s) produced by Pseudomonas sp. GOM7 can be extracted from the culture supernatant of this bacterium with the organic solvent ethyl acetate. Annotation of the Pseudomonas sp. GOM7 genome revealed the presence of several biosynthetic gene clusters predicted to code for possible antimicrobial compounds. Our results further highlight the potential of bacteria from the Gulf of Mexico as a source of novel antimicrobials.

l-Isoleucine-Schiff Base Copper(II) Coordination Polymers: Crystal Structure, Spectroscopic, Hirshfeld Surface, and DFT Analyses.

A new copper(II) coordination polymer was synthesized from the l-isoleucine-Schiff base and characterized by elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, single-crystal X-ray diffraction (XRD) analysis, electronic paramagnetic resonance, and thermogravimetric analysis. XRD analysis confirmed the square planar coordination geometry of metallic centers and a zipper-like polymer structure. Vibrational, electronic, and paramagnetic spectroscopies and thermal analysis were consistent with the crystal structure. A Hirshfeld surface (HS) and density functional theory (DFT) analyses were employed to gain additional insight into interactions responsible for complex packing. The quantitative examination of two-dimensional (2D) fingerprint plots revealed, among other van der Waals forces, the dominating participation of H···H and H···Cl interactions in the molecular packing. The use of computational methods provided great help in detailing the supramolecular interactions occurring in the crystal, which were mainly van der Waals attractions. The electronic transition analysis helped corroborate the electronic transitions observed experimentally in the absorption spectrum. The frequency and vibrational mode analysis gave a deeper insight into the characterization of the CuLCL complex.

Cancer patients' fears related to clinical trial participation: a qualitative study.

Patient-related barriers have hindered cancer patients' abilities to participate in the decision-making processes to participate in clinical trials. However, little is known about patients' emotional barrier of fear and how physicians influence this barrier. We conducted 48 in-depth interviews with cancer patients to determine their knowledge and attitudes about participating in clinical trials, transcribed interviews verbatim, and qualitatively analyzed the transcripts using content analysis. For the purpose of this manuscript, we focused on findings related to the role of the emotional barrier of fear in cancer patients' perceptions of participating in clinical trials. The majority of cancer patients (n = 40, 83.3%) discussed fears surrounding clinical trials, particularly as it related to cancer diagnosis, clinical trial participation, and fear of the unknown. In conclusion, providers might consider addressing the role of fear in patients' considering participating in a clinical trial.

BIGDML-Towards accurate quantum machine learning force fields for materials.

Machine-learning force fields (MLFF) should be accurate, computationally and data efficient, and applicable to molecules, materials, and interfaces thereof. Currently, MLFFs often introduce tradeoffs that restrict their practical applicability to small subsets of chemical space or require exhaustive datasets for training. Here, we introduce the Bravais-Inspired Gradient-Domain Machine Learning (BIGDML) approach and demonstrate its ability to construct reliable force fields using a training set with just 10-200 geometries for materials including pristine and defect-containing 2D and 3D semiconductors and metals, as well as chemisorbed and physisorbed atomic and molecular adsorbates on surfaces. The BIGDML model employs the full relevant symmetry group for a given material, does not assume artificial atom types or localization of atomic interactions and exhibits high data efficiency and state-of-the-art energy accuracies (errors substantially below 1 meV per atom) for an extended set of materials. Extensive path-integral molecular dynamics carried out with BIGDML models demonstrate the counterintuitive localization of benzene-graphene dynamics induced by nuclear quantum effects and their strong contributions to the hydrogen diffusion coefficient in a Pd crystal for a wide range of temperatures.