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Most extant evidence has addressed between-person differences, short-term or cross-sectional associations of electronic nicotine delivery systems (ENDS) use with other substance use, the majority focusing on current rather than escalated use. The present study aimed to examine within-person changes in escalated ENDS use and their associations with individual and combined substance use over a 6-year period.This study used a longitudinal cohort design with US young adults. A generalized linear mixed-model approach was employed to fit a series of weighted logistic regression models. Data were drawn from waves 1-5 of the Population Assessment of Tobacco and Health (PATH) study in the United States. Of the 9110 young adults at baseline, aged 18-24 years, a total of 5042 individuals had matched data across all five waves of assessments.Escalated ENDS use was computed by subtracting the number of days of ENDS use within the past 30 days at waveEscalated ENDS use gradually decreased over time, with the lowest prevalence at wave 4 (4.0%) but sharply increasing at wave 5 (8.4%). Escalated ENDS use was associated with increased odds of using each substance (binge drinking, marijuana use, marijuana vaping, prescription and illicit drugs) and different combinations of polysubstance use between cigarette smoking, binge drinking and marijuana use (Ps 0.05). In addition, sweet/fruit flavor use (versus menthol/mint) was associated with increased likelihood of reporting co-use of cigarettes and marijuana.In the United States, the prevalence of young adults using electronic nicotine delivery systems appears to have increased steadily between 2013 and 2019, although the rate of increase may have started to accelerate in recent years. Escalated electronic nicotine delivery systems use and time-lagged established electronic nicotine delivery systems use appear to be prospectively associated with individual and combined substance use, particularly between cigarettes, alcohol and marijuana. Among established electronic nicotine delivery systems users, sweet/fruit flavor appears to be associated with increased risk of co-using cigarettes and marijuana.

The quantum key distribution (QKD), guaranteed by the principle of quantum physics, is a promising solution for future secure information and communication technology. However, device imperfections compromise the security of real-life QKD systems, restricting the wide deployment of QKD. This study reports a decoy-state BB84 QKD experiment that considers both source and detection imperfections. In particular, we achieved a rigorous finite-key security bound over fiber links of up to 75 km by applying a systematic performance analysis. Furthermore, our study considers more device imperfections than most previous experiments, and the proposed theory can be extended to other discrete-variable QKD systems. These features constitute a crucial step toward securing QKD with imperfect practical devices., 11 pages

The anode is considered to be a key factor to improve the single-chamber bioelectrochemical system's efficiency to degrade oily sludge in sediment while generating electricity. There are few studies on the effect of the anode structure on the performance of oily sludge MFCs systematically. In this paper, an oily sludge bioelectrical system was constructed using carbon felt and carbon plate as anode materials, adjusting the anode material arrangement as transverse and longitudinal, and using different anode materials from single to sextuple anodes. The results of this study showed that the rate of degradation of oily sludge was greater with carbon felt (17.04%) than with the carbon plate (13.11%), with transverse (23.61%) than with the longitudinal (19.82%) arrangement of anodes, and with sextuple anodes (33.72%) than with a single anode (25.26%) in the sediment microbial fuel cells (SMFCs). A similar trend was observed when the voltage, power density, and electromotive force (EMF) of SMFCs were estimated between the carbon felt and carbon plate, transverse and longitudinal arrangements, single and sextuple anodes. It is concluded that the proper adjustment of anode arrangements, using carbon felt as an anode material, and increasing the number of anodes to six may accelerate the rate of degradation of oily sludge in oily sludge sediment microbial fuel cells (SMFCs). Furthermore, the electricity generation performance was also improved.

Electricity-generating bacteria as biocatalysts for microbial fuel cells (MFCs), their species, and power generation performance determine the pollution control and power generation performance of MFCs. And there are few studies on the types and performance of electricity-generating bacteria isolated from oily sludge microbial fuel cells. For improving the power generation performance of oily sludge MFCs, an electricity-generating bacterium was isolated from the oily sludge. More importantly, the adaptability of nitrogen to phosphorus ratio, temperature, and pH of the electricity-generating bacteria were adjusted by a controlled variable method. The results of this study showed that the electricity-generating bacterium was identified as Bacillus cereus, with a rod-shaped cell, about 0.5-1.0 μm in length. The optimal nitrogen-phosphorus ratio, temperature, and pH of MFCs were 4.67:1, 25 ℃, and pH = 7, respectively. Its maximum power density, COD, and oil removal rate was up to 65 mW·m

Quantum key distribution (QKD) is theoretically secure using the principle of quantum mechanics; therefore, QKD is a promising solution for the future of secure communication. Although several experimental demonstrations of QKD have been reported, they have not considered the polarization-dependent loss in state preparation in the key-rate estimation. In this study, we experimentally characterized polarization-dependent loss in realistic state-preparation devices and verified that a considerable PDL exists in fiber- and silicon-based polarization modulators. Hence, the security of such QKD systems is compromised because of the secure key rate overestimation. Furthermore, we report a decoy-state BB84 QKD experiment considering polarization-dependent loss. Finally, we achieved rigorous finite-key security bound over up to 75 km fiber links by applying a recently proposed security proof. This study considers more realistic source flaws than most previous experiments; thus, it is crucial toward a secure QKD with imperfect practical devices.

Integrated photonics provides a promising platform for quantum key distribution (QKD) system in terms of miniaturization, robustness and scalability. Tremendous QKD works based on integrated photonics have been reported. Nonetheless, most current chip-based QKD implementations require additional off-chip hardware to demodulate quantum states or perform auxiliary tasks such as time synchronization and polarization basis tracking. Here, we report a demonstration of resource-efficient chip-based BB84 QKD with a silicon-based encoder and decoder. In our scheme, the time synchronization and polarization compensation are implemented relying on the preparation and measurement of the quantum states generated by on-chip devices, thus no need additional hardware. The experimental tests show that our scheme is highly stable with a low intrinsic QBER of $0.50\pm 0.02\%$ in a 6-h continuous run. Furthermore, over a commercial fiber channel up to 150 km, the system enables realizing secure key distribution at a rate of 866 bps. Our demonstration paves the way for low-cost, wafer-scale manufactured QKD system., Comment: comments are welcomed. Accepted by Photonics Research

Quantum secure direct communication (QSDC) has been demonstrated in both fiber-based and free-space channels using attenuated lasers. Decoy-state QSDC by exploiting four decoy states has been proposed to address the problem of photon-number-splitting attacks caused by the use of attenuated lasers. In this study, we present an analysis of the practical aspects of decoy-state QSDC. First, we design a two-decoy-state protocol that only requires two decoy states, thereby significantly reducing experimental complexity. Second, we successfully perform full parameter optimization for a real-life QSDC system by introducing a genetic algorithm. Our simulation results show that the two-decoy-state protocol could be the best choice for developing a practical QSDC system. Furthermore, full optimization is crucial for a high-performance QSDC system. Our work serves as a major step toward the further development of practical decoy-state QSDC systems.

Linear ubiquitin (Ub) chains regulate many cellular processes, including NF-κB immune signalling. Pathogenic bacteria have evolved to secrete effector proteins that harbour deubiquitinase activity into host cells to disrupt host ubiquitination signalling. All previously identified effector deubiquitinases hydrolyse isopeptide-linked polyubiquitin (polyUb). It has been a long-standing question whether bacterial pathogens have evolved an effector deubiquitinase to directly cleave linear Ub chains. In this study, we performed extensive screening of bacterial pathogens and found that Legionella pneumophila-the causative agent of human Legionnaire's disease-encodes an effector protein, RavD, which harbours deubiquitinase activity exquisitely specific for linear Ub chains. RavD hydrolyses linear Ub chains but not any type of isopeptide-linked polyUb. The crystal structure of RavD with linear diubiquitin reveals that RavD adopts a papain-like fold with a Cys-His-Ser catalytic triad. The Ub-binding surface and specific interacting residues in RavD determine its specificity for Met1 linkages. RavD prevents the accumulation of linear Ub chains on Legionella-containing vacuoles established by the pathogen in host cells to inhibit the NF-κB pathway during infection. This study identified a unique linear Ub chain-specific effector deubiquitinase and indicates its potential application as a tool to dissect linear polyUb-mediated signalling in mammalian cells.

Microbial fuel cell (MFC) technology is a simple way to accelerate the treatment of the oily sludge which is a major problem affecting the quality of oil fields and surrounding environment while generating electricity. To investigate the oil removal and the characteristics of changes in the composition of bacteria, sediment microbial fuel cells (SMFCs) supplemented with oily sludge was constructed. The results showed that the degradation efficiency of total petroleum hydrocarbon (TPH) of SMFC treatment was 10.1 times higher than the common anaerobic degradation. In addition, the degradation rate of n-alkanes followed the order of high carbon number > low carbon number > medium carbon number. The odd–even alkane predominance (OEP) increased, indicating that a high contribution of even alkanes whose degradation predominates. The OUT number, Shannon index, AEC index, and Chao1 index of the sludge treated with SMFC (YN2) are greater than those of the original sludge (YN1), showing that the microbial diversity of sludge increased after SMFC treatment. After SMFC treatment the relative abundance of Chloroflexi, Bacteroidia and Pseudomonadales which are essential for the degradation of the organic matter and electricity production increased significantly in YN2. These results will play a crucial role in improving the performance of oily sludge MFC.

Bacterial toxin fatty-acylates lysine residues A toxin produced by the bacterium that causes cholera has a catalytic activity that contributes to its effects on the cytoskeleton of host cells. Zhou et al. determined the protein structure of the Rho guanosine triphosphatase (GTPase)–inactivation domain of the toxin from Vibrio cholerae and found it to be similar to that of a human fatty acyltransferase. Indeed, the toxin peptide could catalyze fatty acylation of lysine residues of Rho-family GTPases, which regulate the actin cytoskeleton. Such covalent modification of lysine residues in mammalian proteins had been noted before, but the enzymes responsible were not known. Science , this issue p. 528

Ubiquitination is essential for numerous eukaryotic cellular processes. Here, we show that the type III effector CteC from Chromobacterium violaceum functions as an adenosine diphosphate (ADP)-ribosyltransferase that specifically modifies ubiquitin via threonine ADP-ribosylation on residue T66. The covalent modification prevents the transfer of ubiquitin from ubiquitin-activating enzyme E1 to ubiquitin-conjugating enzyme E2, which inhibits subsequent ubiquitin activation by E2 and E3 enzymes in the ubiquitination cascade and leads to the shutdown of polyubiquitin synthesis in host cells. This unique modification also causes dysfunction of polyubiquitin chains in cells, thereby blocking host ubiquitin signaling. The disruption of host ubiquitination by CteC plays a crucial role in C. violaceum colonization in mice during infection. CteC represents a family of effector proteins in pathogens of hosts from different kingdoms. All the members of this family specifically ADP-ribosylate ubiquitin. The action of CteC reveals a new mechanism for interfering with host ubiquitination by pathogens.

Quantum Key Distribution (QKD) is a technology that allows secure key exchange between two distant users. A widespread adoption of QKD requires the development of simple, low-cost, and stable systems. However, implementation of the current QKD requires a complex self-alignment process during the initial stage and an additional hardware to compensate the environmental disturbances. In this study, we have presented the implementation of a simple QKD with the help of a stable transmitter-receiver scheme, which simplifies the self-alignment and is robust enough to withstand environmental disturbances. In case of the stability test, the implementation system is able to remain stable for 48 hours and exhibits an average quantum bit error rate of less than 1\% without any feedback control. The scheme is also tested over a fiber spool, obtaining a stable and secure finite key rate of 7.32k bits per second over a fiber spool extending up to 75 km. The demonstrated long-term stability and obtained secure key rate prove that our method of implementation is a promising alternative for practical QKD systems, in particular, for Cubesat platform and satellite applications., Comment: 13 pages, 3 figures,accepted by Optics Letters

In this article, we show that the Brownian motion on the circle constructed by Levy (1959) is a regular Euclidean Brownian motion on the half-circle with its own mirror image on the other half-circle, and is degenerated in the sense of Minlos (1959). This raises the question of what the white noise is on the circle. We then formally define the white noise space and its associated Brownian bridge on the circle.

The cubic smoothing spline has been a popular method for detrending tree-ring data since the 1980s. The common implementation of this procedure (e.g., ARSTAN, dplR) uses a unique method for determining the smoothing parameter that is widely known as the %n criterion. However, this smoothing parameter selection method carries the assumption that end point effects are ignorable. In this paper, we complete the mathematical derivation and show how the original method differs from the complete version, both in the interpretation of the smoothing parameter and in the spline fit. Frequency response curves (FRC) demonstrate how the smoothing parameter is affected by the original assumption. For example, the FRC results indicate that a tree core of 250-year length has a 14% difference in the cut-off frequency when looking at the 67%n criterion. The FRC analysis shows that the existing approach produces a more flexible fit than anticipated, i.e., it is removing more variance than previously thought. For example, a 67%n spline under the existing approach corresponds to a 53%n spline fit. By using both simulated tree-core sequences and a dataset from a Midwest forest, we discuss which conditions result in greater differences between the spline fits and which conditions will have small differences. Tree-core sequences that have more curvature, such as a large-amplitude growth release, will lead to greater differences. Finally, we provide approximations to the end-point effect procedure. For example, using an 83%n criterion under the original approach produces a spline fit approximating the 67%n fit under the complete approach. These approximations could be easily implemented within existing programs like ARSTAN.

Intrinsic random functions (IRF) provide a versatile approach when the assumption of second-order stationarity is not met. Here, we develop the IRF theory on the circle with its universal kriging application. Unlike IRF in Euclidean spaces, where differential operations are used to achieve stationarity, our result shows that low-frequency truncation of the Fourier series representation of the IRF is required for such processes on the circle. All of these features and developments are presented through the theory of reproducing kernel Hilbert space. In addition, the connection between kriging and splines is also established, demonstrating their equivalence on the circle., Comment: 14 pages, initial version

The extent to which social norms (injunctive and descriptive) are associated with collegiate alcohol use—including binge drinking—has been examined at length, but studies examining the efficacy of interventions derived thereof have reported mixed outcomes. This study examines data from 5,124 college students at 13 different colleges collected by the 2010 Indiana College Substance Use Survey in order to further elucidate the relationship between social norms and binge drinking. We apply seven different regression models to the data, finding the zero-inflated negative binomial (ZINB) model to fit best, likely due to the unique characteristics of the binge-drinking variable; individuals who do not consume any alcohol do not binge drink, inflating the frequency of zeroes for the variable. We contrast key findings from this model to those from other regression models as well as information from the literature and provide preliminary suggestions as to future directions for social norms research as it re...

There are n cards serially numbered from 1 to n. The cards are shuffled and placed in a line one after the other on top of a table with faces up. The numbers on the faces are read from left to right. If there are consecutive numbers in increasing order of magnitude the corresponding cards are merged into one. After the merger, the cards are numbered serially from one to whatever the number of cards we now have. The cards are shuffled and placed in a line one after another on top of the table with faces up. The process continues until we have only one card left. In this paper, we develop a probabilistic recurrence relation approach to obtain the mean, variance, and distribution of the number of shuffles needed. A Markov chain formulation and its properties are discussed in the paper as well.

Leucine-rich repeat G-protein-coupled receptors (LGRs) are a unique class of G-protein-coupled receptors characterized by a large extracellular domain to recognize ligands and regulate many important developmental processes. Among the three groups of LGRs, group B members (LGR4-6) recognize R-spondin family proteins (Rspo1-4) to stimulate Wnt signaling. In this study, we successfully utilized the "hybrid leucine-rich repeat technique," which fused LGR4 with the hagfish VLR protein, to obtain two recombinant human LGR4 proteins, LGR415 and LGR49. We determined the crystal structures of ligand-free LGR415 and the LGR49-Rspo1 complex. LGR4 exhibits a twisted horseshoe-like structure. Rspo1 adopts a flat and β-fold architecture and is bound in the concave surface of LGR4 in the complex through electrostatic and hydrophobic interactions. All the Rspo1-binding residues are conserved in LGR4-6, suggesting that LGR4-6 bind R-spondins through an identical surface. Structural analysis of our LGR4-Rspo1 complex with the previously determined LGR4 and LGR5 structures revealed that the concave surface of LGR4 is the sole binding site for R-spondins, suggesting a one-site binding model of LGR4-6 in ligand recognition. The molecular mechanism of LGR4-6 is distinct from the two-step mechanism of group A receptors LGR1-3 and the multiple-interface binding model of group C receptors LGR7-8, suggesting LGRs utilize the divergent mechanisms for ligand recognition. Our structures, together with previous reports, provide a comprehensive understanding of the ligand recognition by LGRs.

Many important environmental, geographic, and geophysical variables are observed at the global scale, so it is important to extend point-pattern methods to the sphere. Here, we develop the K function on the sphere and then evaluate several global data structures and networks. The assumption of complete spatial randomness (CSR) gives a K function that is proportional to the square of distance in Euclidean space, but we find that CSR on the sphere is proportional to 1 − cos ( angular distance ) . To evaluate the spherical K function, we analyze two global data structures: latitude-longitude and equidistant hexagonal grids. Due to over-representation of polar regions, latitude-longitude grids produce clustered point patterns. The hexagonal grid is equal-area on the sphere and produces a dispersed point pattern. We also analyze the structure of an observing system for global climate research that is intended to have relatively even spatial coverage. We find that, due to its coastal and continental biases, the climate-station network produces clustered point patterns over a range of distances. Our focus is on planetary-scale geographic point distributions, but we foresee applications of spherical K functions in disciplines such as astronomy, geodetics, anatomy, and neuroscience. Software for spherical point-pattern analysis is available from the authors.

When the correlation theory is considered for the processes with random stationary increments, Yaglom (1955) has developed the spectral representation theory. In this note, we complete this development by obtaining the inversion formula of the spectrum in terms of the structure function.

Permutation tests for serial independence using three different statistics based on empirical distributions are proposed. These tests are shown to be consistent under the alternative of m-dependence and are all simple to perform in practice. A small simulation study demonstrates that the proposed tests have good power in small samples. The tests are then applied to Canadian gross domestic product (GDP data), corroborating the random-walk hypothesis of GDP growth.

The objective of this study was to identify characteristics of informal caregivers, caregiving, and the people with multiple sclerosis (MS) receiving assistance that are associated with reduced caregiver employment. Data were collected during telephone interviews with 530 MS caregivers, including 215 employed caregivers, with these survey data analyzed using logistic regression. Poorer cognitive ability by the care recipient to make decisions about daily tasks and more caregiving hours per week predicted reduced caregiver employment. Better physical health domains of caregiver quality of life were associated with significantly lower odds of reduced employment. Health professionals treating informal caregivers, as well as those treating people with MS, need to be aware of respite, support, and intervention programs available to MS caregivers and refer them to these programs, which could reduce the negative impact of caregiving on employment.

The multifunctional autoprocessing repeats-in-toxin (MARTX) toxins are a family of large toxins that are extensively distributed in bacterial pathogens. MARTX toxins are autocatalytically cleaved to multiple effector domains, which are released into host cells to modulate the host signaling pathways. The Rho guanosine triphosphatase (GTPase) inactivation domain (RID), a conserved effector domain of MARTX toxins, is implicated in cell rounding by disrupting the host actin cytoskeleton. We found that the RID is an N

Spatial processes having covariance functions that depend solely on the distance between locations are known as homogeneous. Many random processes on the sphere are not homogeneous, especially in the latitudinal dimension. As a result, we study a class of statistical processes that exhibit axial symmetry, whereby their covariance function depends on differences in longitude alone. We develop a new and simplified representation for a valid axially symmetric process, reducing computational complexity considerably. In addition, we explore longitudinally reversible processes and the construction of parametric models for axially symmetric processes.

The Internet is used to help informal caregivers provide assistance to people with chronic illness and disability. We identified factors associated with Internet use by informal caregivers assisting people with multiple sclerosis (MS) using a logistic regression model. Duration of MS in the person receiving care and caregiver age predicted lower Internet use. More hours per week providing care and higher caregiver educational level increased odds of Internet use. The Internet can be a low-cost service delivery option to provide education and support to caregivers assisting people with MS.

Counting is one of the most basic procedures in mathematics and statistics. In statistics literature it is usually done via the proportion estimation method. In this article we manifest a radically different counting procedure first proposed in the late 1990's based on the techniques of quantum computation. It combines two major tools in quantum computation, quantum Fourier transform and quantum amplitude amplification, and shares similar structure to the quantum part of the celebrated Shor's factoring algorithm. We present complete details of this quantum counting algorithm and the analysis of its error distribution. Comparing it with the conventional proportion estimation method, we demonstrate that this quantum approach achieves much faster convergence rate than the classical approach.

Identify factors of informal caregivers, caregiving, and people with multiple sclerosis (MS) receiving assistance that are associated with perceptions of caregiver accomplishment.National data were collected in a telephone interview survey of 530 informal caregivers and analyzed using an ordered logistic regression model to identify factors associated with perceptions of caregiver accomplishment among 442 of these informal caregivers (caregivers providing all data in their survey responses needed for the regression model).We found that age of the person with MS and duration of caregiving measured by the number of hours per week the caregiver assisted the person with MS were significantly linked to positive perceptions of accomplishment. Conversely, the caregiver's perception that assisting the person with MS was emotionally draining, a spousal relationship, and caregiver education levels were significantly associated with negative perceptions of accomplishment.Health professionals treating people with MS and their caregivers should be sensitive to the impact caregiving has on the emotional needs of caregivers and to the unique support needs of spousal caregivers. Health practitioners also should be sensitive to the variety of benefit-finding themes expressed by caregivers to facilitate the caregivers' efforts to discover gains in their experiences assisting people with MS, such as perceptions that caregiving provides a sense of accomplishment.

Covariance and variogram functions have been extensively studied in Euclidean space. In this article, we investigate the validity of commonly used covariance and variogram functions on the sphere. In particular, we show that the spherical and exponential models, as well as power variograms with 0

In the study of intrinsically stationary spatial processes, a new nonparametric variogram estimator is proposed through its spectral representation. The methodology is based on estimation of the variogram's spectrum by solving a regularized inverse problem through quadratic programming. The estimated variogram is guaranteed to be conditionally negative-definite. Simulation shows that our estimator is flexible and generally has smaller mean integrated squared error than the parametric estimator under model misspecification. Our methodology is applied to a spatial dataset of decadal temperature changes. Copyright 2011, Oxford University Press.

Background: Caregiver burden is a multidimensional response to many factors associated with providing assistance to people with multiple sclerosis (MS), including physical, psychological, emotional, and social stressors. Objective: The aim of this analysis was to identify the characteristics of male informal caregivers, the assistance provided, and the people receiving assistance who were associated with the burden of care. Methods: Data were collected from a national survey (which included the Mental Component Summary of the SF-8 Health Survey) of informal caregivers and analyzed using an ordered logistic regression model to identify characteristics associated with burden among male informal caregivers. Results: Greater burden among male caregivers was associated with significantly greater hours per week providing assistance (P = 0.009) and significantly greater restriction on the caregiver's ability to perform daily activities (P < 0.001) due to assisting the person with MS. We found a strong association between the perception of burden and the mental health status of the male caregiver (P < 0.001). Conclusions: Our findings highlight the strong association of caregiver burden and the Mental Component Summary of the SF-8. Reducing burden may improve the mental health of informal caregivers. Health professionals treating either male caregivers or people with MS should be sensitive to the impact that providing assistance has on the mental health of informal caregivers.

To identify factors affecting the health-related quality of life (HRQOL) of informal caregivers assisting people with (multiple sclerosis) MS who have greater functional impairment.Data were collected in a national survey of 530 people who provided informal care to people with MS. Multiple linear regression models analyzed these data.Poorer overall health for the person with MS, stronger agreement by caregivers that care giving was burdensome or emotionally draining, and the caregiver's need for mental health counseling in the past 12 months were associated with lower mental dimensions of HRQOL for the informal caregiver. Greater caregiver satisfaction with the access the person with MS had to MS-focused care was associated with higher mental dimensions of HRQOL among caregivers.Increasing access to MS-focused care could improve not only the health of people with MS, but also improve the mental dimensions of caregiver HRQOL. Our findings highlight the importance of addressing the mental health needs of informal caregivers assisting people with MS.

Background About one quarter of people with multiple sclerosis (MS) will need long term care during their disease, with about 5% to 10% requiring extended nursing home care. The study objective was to identify perceptions of informal caregivers associated with the possibility of future nursing home admission for people with MS. Methods Data were collected in a national survey of informal caregivers (78% were spouses) to people with MS. An ordered logistic regression model analyzed contributions that characteristics of the person with MS and caregiver made to the perceived probability of future nursing home admission. Results Aging, bowel dysfunction, poorer health, and functional decline in the person with MS, as well as caregiver burden, were associated with increased probability of future admission. Higher family income and greater satisfaction with access to MS-focused care were associated with lower risk of nursing home admission. Conclusions The rehabilitative, therapeutic, supportive, and maintenance services that contribute to MS-focused care could assist the person with MS and the caregiver adapt to the symptoms that interfere with the ability of the person with MS to function independently in daily life. Informal caregivers provided insights into factors associated with the perceived probability of future nursing home admission, gaining a better understanding of people with MS at risk for institutional care.

Multiple sclerosis (MS) is an unpredictable disease that can have physical, psychological, and social impacts, reducing health-related quality of life (HRQOL). The objective of this study was to identify factors associated with HRQOL among young adults with MS. Survey data were collected from 100 people with MS aged 18 to 31 years, with 93 participants providing all data needed for analyses of our regression models. The survey cohort was recruited from the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry (now the NARCOMS/Global Patient Registry). Multiple linear regression models were used to analyze the data, with the Physical Component Summary and the Mental Component Summary of the 8-item Short Form Health Status Survey serving as dependent variables. Independent variables were other survey responses, including demographic, disease, and treatment characteristics. The results indicated that full-time employment, relapsing-remitting course of MS, and satisfaction with access to MS-focused care were associated with better physical dimensions of HRQOL. Conversely, MS symptoms that interfered with daily life and perceptions of not having as good a social life as other people of comparable age were linked to poorer physical dimensions of HRQOL. Worsening MS symptoms, not having as good a social life as other people of comparable age, and seeing a mental health professional in the previous 12 months were associated with poorer mental dimensions of HRQOL. Our study highlights the association of MS-focused care with better physical dimensions of HRQOL among young adults with MS.

In multivariate geostatistics, suppose that we relax the usual second-order-stationarity assumptions and assume that the component processes are intrinsic random functions of general orders. In this article, we introduce a generalized cross-covariance function to describe the spatial cross-dependencies in multivariate intrinsic random functions. A nonparametric method is then proposed for its estimation. Based on this class of generalized cross-covariance functions, we give cokriging equations for multivariate intrinsic random functions in the presence of measurement error. A simulation is presented that demonstrates the accuracy of the proposed nonparametric estimation method. Finally, an application is given to a dataset of plutonium and americium concentrations collected from a region of the Nevada Test Site used for atomic-bomb testing.

Spatial stochastic processes that are modeled over the entire Earth’s surface require statistical approaches that directly consider the spherical domain. In practice, such processes rarely are second-order stationary — that is, they do not have constant mean values or the covariance function that depends only on their angular distance. Here, in order to model non-stationary processes on the sphere, we extend the notion of intrinsic random functions and show that low-frequency truncation plays an essential role. We show that these developments can be presented through the theory of reproducing kernel Hilbert space. In addition, the link between universal kriging and splines is carefully investigated, whereby we show that thin-plate splines are non-applicable for surface fitting on the sphere.