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The global marine environment is increasingly affected by human activities causing climate change, eutrophication, and pollution. These factors influence the metabolic mechanisms of phytoplankton species, such as diatoms. Among other pollutant agents, heavy metals can have dramatic effects on diatom viability. Detailed knowledge of the interaction of diatoms with metals is essential from both a fundamental and applicative point of view. To this aim, we assess terahertz time-domain spectroscopy as a tool for sensing the diatoms in aqueous systems which mimic their natural environment. Despite the strong absorption of terahertz radiation in water, we show that diatoms can be sensed by probing the water absorption enhancement in the terahertz range caused by the water-diatom interaction. We reveal that the addition of metal dopants affects this absorption enhancement, thus enabling the monitoring of the toxic effects of metals on diatoms using terahertz spectroscopy. We demonstrate that this technique can detect the detrimental effects of heavy metals earlier than conventional methods such as microscopy, enzymatic assays, and molecular analyses aimed at assessing the overexpression of genes involved in the heavy metal-stress response.

The well-being of the family caregivers of people with serious mental illnesses (SMIs) is a crucial success factor in the recovery of the afflicted family member. This cross-sectional quantitative study examined the associations between the use of formal mental health services, self-efficacy, and positive attitudes and their effects on the well-being of Asian American family caregivers of people with SMIs. Using convenience and snowball sampling, 116 Asian American family caregivers of people with SMIs in Northern California were recruited for this study. We found that formal mental health service utilization predicted an enhanced sense of self-efficacy. Higher levels of self-efficacy were related to attitudes being more positive, and these positive attitudes contributed to enhanced overall well-being. These findings suggest that mental health professionals should develop culturally competent and tailored services for Asian American family caregivers to support self-efficacy, which is fundamental to maintaining positive attitudes and promoting wellness., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Holographic photomobile polymers (H-PMP) are a novel class of photomobile materials in which holograms can be optically recorded. They can be used in a large variety of applications, including optical switches and color selectors. In this work, we show one of the most important properties of the photomobile film, which is the photophobicity of the unpolymerized parts of the photomobile mixture. In order to investigate this property, we recorded a transmission phase grating on an H-PMP film, and used a different experimental technique to measure the diffraction efficiency, surface tension, and mixture properties. The results allowed for a better understanding of the mechanism of the light-controlled bending observed in these compounds.

Holographic microscopes are emerging as suitable tools for in situ diagnostics and environmental monitoring, providing high-throughput, label-free, quantitative imaging capabilities through small and compact devices. In-line holographic microscopes can be realized at contained costs, trading off complexity in the phase retrieval process and being limited to sparse samples. Here we present a 3D printed, cost effective and field portable off-axis holographic microscope based on the concept of holographic microfluidic slide. Our scheme removes complexity from the reconstruction process, as phase retrieval is non iterative and obtainable by hologram demodulation. The configuration we introduce ensures flexibility in the definition of the optical scheme, exploitable to realize modular devices with different features. We discuss trade-offs and design rules of thumb to follow for developing DH microscopes based on the proposed solution. Using our prototype, we image flowing marine microalgae, polystyrene beads, E.coli bacteria and microplastics. We detail the effect on the performance and costs of each parameter, design, and hardware choice, guiding readers toward the realization of optimized devices that can be employed out of the lab by non-expert users for point of care testing., Competing Interests: The authors declare no conflicts of interest., (© 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.)

The intracellular dynamics of onion epidermal cells during the dehydration process is observed by holographic microscopy. Both the nucleus and cytoplasm are accurately revealed by quantitative phase imaging while dehydration takes place. Indeed, we notice that the contrast of phase images increases with the decrease in cellular water content. We foresee that such a dehydrating process can be effective for improving phase contrast, thus permitting better imaging of plant cells with the scope of learning more about cellular dynamics and related phenomena. Exploiting this concept, we observe intracellular cytoplasmic circulation and transport of biological material.

The combined use of ultrasound radiation and microfluidics is a promising tool for aiding the development of lab-on-a-chip devices. In this study, we show that the rotation of linear aggregates of micro-particles can be achieved under the action of acoustic field pressure. This novel manipulation is investigated by tracking polystyrene beads of different sizes through the 3D imaging features of digital holography (DH). From our analysis it is understood that the positioning of the micro-particles and their aggregations are associated with the effect of bulk acoustic radiation forces. The observed rotation is instead found to be compatible with the presence of acoustic streaming patterns as evidenced by our modelling and the resulting numerical simulation. Furthermore, the rotation frequency is shown to depend on the input voltage applied on the acoustic device. Finally, we demonstrate that we can take full advantage of such rotation by combining it with quantitative phase imaging of DH for a significant lab-on-a-chip biomedical application. In fact, we demonstrate that it is possible to put in rotation a linear aggregate of erythrocytes and rely on holographic imaging to achieve a full phase-contrast tomography of the aforementioned aggregate.

Background: The Heart Failure Somatic Perception Scale (HFSPS) is a four-factor instrument used to assess how bothersome are 18 physical signs and symptoms of heart failure. To date, construct validity and reliability of the HFSPS have been evaluated in only one American study and never in a European population., Aim: To evaluate psychometric properties (validity and reliability) of the HFSPS in a European heart failure population., Methods: This was an Italian multicentre study in which the HFSPS factorial structure was assessed using confirmatory factor analysis. Criterion related validity of the HFSPS was evaluated by correlating its factor scores with the Kansas City Cardiomyopathy Questionnaire (KCCQ) scores using Pearson's r . The HFSPS internal consistency reliability was evaluated using the factor score determinacy coefficient, Cronbach's α and model-based internal consistency index., Results: Most of the participants ( n =321) were male (56.6%), with a mean age of 71.48 years (SD, 12.75) and in New York Heart Association class II (61.8%). The confirmatory factor analysis, testing the original HFSPS four-factor structure (dyspnoea, chest discomfort, early and subtle, and oedema), resulted in the following supportive fit indices: χ 2 (126, N =321)=337.612, p <0.001, comparative fit index =0.920, Tucker-Lewis index =0.903, root mean square error of approximation =0.072 and standardized root mean square residual =0.045. With regard to the criterion related validity, all the correlations with the KCCQ were statistically significant. The HFSPS reliability resulted in factor score determinacy coefficients ⩾ 0.87 and Cronbach's α ⩾ 0.75, with the exception of the two-item chest discomfort subscale; the model-based reliability coefficient was 0.914., Conclusion: The validity and reliability of the HFSPS were supportive in this European sample. The HFSPS can be used to assess how bothersome heart failure signs and symptoms are in order to improve their management.

Background: Caregiver contribution to heart failure (HF) self-care maintenance and management is important in HF care. Literature remains unclear regarding which practices caregivers perform to contribute to self-care for patients with HF, especially in Southern Europe., Objective: The objective of this study was to describe caregiver contributions to HF self-care maintenance (ie, treatment adherence and symptom monitoring) and management (ie, managing HF symptoms when they occur)., Methods: Forty HF caregivers were enrolled from 3 outpatient clinics in Italy for a qualitative descriptive study. Data were collected with a semistructured interview and analyzed using content analysis., Results: Caregivers were 53.6 years old on average and mostly female (63.5%). Caregiver contributions to self-care maintenance included practices related to (1) monitoring medication adherence, (2) educating patients about HF symptom monitoring, (3) motivating patients to perform physical activity, and (4) reinforcing dietary restrictions. However, some of these practices were incorrect (eg, weighing the patient only once a week). Caregiver contributions to self-care management included practices related to (1) symptom recognition and (2) treatment implementation. Caregivers were able to recognize symptoms of HF exacerbation (eg, breathlessness) but lacked confidence regarding treatment implementation (eg, administering an extra diuretic)., Conclusions: Although caregivers described contributing to patients' HF self-care maintenance and management, some of their practices were incorrect. Because the caregiver contributions to HF self-care can improve patient outcomes, clinicians should routinely assess caregiver HF self-care practices and provide education and reinforcement regarding evidence-based practices.

Background: Higher patient-caregiver mutuality is associated with improved patient and caregiver outcomes, but no studies have tested the psychometric characteristics of the mutuality scale (MS) in heart failure (HF) patient and caregiver population., Objectives: To test the validity and reliability of the MS., Methods: A cross-sectional design. The MS validity and reliability were tested with confirmatory factor analysis (CFA) and hypothesis testing, and with Cronbach's alpha and model-based internal consistency index, respectively., Results: CFA supported the validity of the MS in the HF patient and caregiver versions. Hypothesis testing showed significant correlations between both versions of the MS and anxiety, depression, quality of life, and self-care. Also, MS caregiver version scores correlated significantly with caregiver preparedness. Cronbach's alphas and the model-based internal consistency index ranged between 0.72 and 0.94 in both versions., Conclusions: The Mutuality Scale showed supportive validity and reliability for HF patients and caregivers., (Copyright © 2018. Published by Elsevier Inc.)

Mutuality in patient-caregiver dyad may improve heart failure (HF) patient self-care and caregiver contribution to self-care, but literature is scarce. We evaluated the influence of mutuality and its dimensions on patient-caregiver dyad self-care. A sample of 366 HF patient-caregiver dyads was enrolled. The Actor-Partner Interdependence Model was used to identify the influence of individual patient and caregiver mutuality on their own self-care (actor effect) and on partner self-care (partner effect). The total mutuality score had an actor effect on patient self-care maintenance (i.e., behaviors aimed at maintaining HF stability) and on patient and caregiver self-care confidence. Total score of patient mutuality also had a partner effect on caregiver self-care management (i.e., responses to symptoms of HF exacerbation). Specific mutuality dimensions had different actor and partner effects on patient and caregiver self-care. Interventions to improve mutuality in HF patient-caregiver dyads may influence patient self-care and caregiver contribution to self-care.

Space-time digital holography (STDH) exploits the object motion to record the hologram in a hybrid ST domain. This representation adds new capabilities to conventional DH, e.g., unlimited field of view and variable phase shifting. This is the best candidate for imaging biological samples flowing in microfluidic channels. Here, we show that STDH is able to improve the spatial resolution as well. Different from other super-resolution approaches, stitching between holograms or their spectra is no longer required. Moreover, we introduce a new oblique STDH modality to record and process hybrid ST representations. This allows improving resolution in 2D with one single object scan, paving the way to the use of STDH for super-resolution imaging onboard microfluidic devices.

Digital holography (DH) has emerged as one of the most effective coherent imaging technologies. The technological developments of digital sensors and optical elements have made DH the primary approach in several research fields, from quantitative phase imaging to optical metrology and 3D display technologies, to name a few. Like many other digital imaging techniques, DH must cope with the issue of speckle artifacts, due to the coherent nature of the required light sources. Despite the complexity of the recently proposed de-speckling methods, many have not yet attained the required level of effectiveness. That is, a universal denoising strategy for completely suppressing holographic noise has not yet been established. Thus the removal of speckle noise from holographic images represents a bottleneck for the entire optics and photonics scientific community. This review article provides a broad discussion about the noise issue in DH, with the aim of covering the best-performing noise reduction approaches that have been proposed so far. Quantitative comparisons among these approaches will be presented., Competing Interests: The authors declare that they have no conflict of interest.

The development of techniques able to characterize and map the pressure field is crucial for the widespread use of acoustofluidic devices in biotechnology and lab-on-a-chip platforms. In fact, acoustofluidic devices are powerful tools for driving precise manipulation of microparticles and cells in microfluidics in non-contact modality. Here, we report a full and accurate characterization of the movement of particles subjected to acoustophoresis in a microfluidic environment by holographic imaging. The particle displacement along the direction of the ultrasound wave propagation, coinciding with the optical axis, is observed and investigated. Two resonance frequencies are explored, varying for each the amplitude of the applied signal. The trajectories of individual tracers, accomplished by holographic measurements, are fitted with the theoretical model thus allowing the retrieval of the acoustic energy densities and pressure amplitudes through full holographic analysis. The absence of prior calibration, being independent of the object shape and the possibility of implementing automatic analysis make the use of holography very appealing for applications in devices for biotechnologies.

Background: Heart failure (HF) self-care is important in reducing clinical events (all-cause mortality, emergency room visits and hospitalizations). HF self-care behaviors are multidimensional and include maintenance (i.e. daily adherence behaviors), management (i.e. symptom response behaviors) and consulting behaviors (i.e. contacting a provider when appropriate). Across these dimensions, patterns of successful patient engagement in self-care have been observed (e.g. successful in one dimension but not in others), but no previous studies have linked patterns of HF self-care to clinical events., Objectives: To identify patterns of self-care behaviors in HF patients and their association with clinical events., Methods: This was a prospective, non-experimental, cohort study. Community-dwelling HF patients (n = 459) were enrolled across Italy, and clinical events were collected one year after enrollment. We measured dimensions of self-care behavior with the Self-Care of HF Index (maintenance, management, and confidence) and the European HF Self-care Behavior Scale (consulting behaviors). We used latent class mixture modeling to identify patterns of HF self-care across dimensions, and Cox proportional hazards modeling to quantify event-free survival over 12 months of follow-up., Results: Patients (mean age 71.8 ± 12.1 years) were mostly males (54.9%). Three patterns of self-care behavior were identified; we labeled each by their most prominent dimensional characteristic: poor symptom response, good symptom response, and maintenance-focused behaviors. Patients with good symptom response behaviors had fewer clinical events compared with those who had poor symptom response behaviors (adjusted hazard ratio = 0.66 [0.46-0.96], p = 0.03). Patients with poor symptom response behaviors had the most frequent clinical events. Patients with poor symptom response and those with maintenance-focused behaviors had a similar frequency of clinical events., Conclusions: Self-care is significantly associated with clinical events. Routine assessment, mitigation of barriers, and interventions targeting self-care are needed to reduce clinical events in HF patients., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Preventing hospitalization and improving event-free survival are primary goals of heart failure (HF) treatment according to current European Society of Cardiology guidelines; however, substantial uncertainty remains in our ability to predict risk and improve outcomes. Although caregivers often assist patients to manage their HF, little is known about their influence on clinical outcomes., Aims: To quantify the influence of patient and caregiver characteristics on patient clinical event risk in HF., Methods: This was a secondary analysis of data using a sample of Italian adults with HF and their informal caregivers ( n = 183 patient-caregiver dyads). HF patients were followed over 12 months for the following clinical events: hospitalization for HF, emergency room visit for HF or all-cause mortality. Influence of baseline caregiver- and patient-level factors (patient and caregiver age; dyad relationship type; patient New York Heart Association (NYHA) Class, cognition, and comorbidities; and caregiver strain, mental health status, and contributions to HF self-care) on patient risk of death or hospitalization/emergency room use was quantified using Cox proportional hazards regression., Results: Over the course of follow up, 32.8% of patients died, 19.7% were hospitalized for HF and 10.4% visited the emergency room. Higher caregiver strain, better caregiver mental health status and greater caregiver contributions to HF self-care maintenance were associated with significantly better event-free survival. Worse patient functional class and greater caregiver contributions to patient self-care management were associated with significantly worse patient event-free survival., Conclusion: Considering caregiving factors together with patient factors significantly increases our understanding of patient clinical event risk in HF.

We have introduced a new hybrid fabrication method for lab-on-a-chip devices through the combination of femtosecond laser micromachining and removable insert micro-injection molding. This method is particularly suited for the fast prototyping of new devices, while maintaining a competitive low cost. To demonstrate the effectiveness of our approach, we designed, fabricated, and tested a completely integrated flow cytometer coupled to a portable media device. The system operation was tested with fluorescent plastic micro-bead solutions ranging from 100 beads/μL to 500 beads/μL. We demonstrated that this hybrid lab-on-a-chip fabrication technology is suitable for producing low-cost and portable biological microsystems and for effectively bridging the gap between new device concepts and their mass production., Competing Interests: The authors declare no conflict of interest.

Background: Heart failure (HF) patients need to follow a strict pharmacological and nonpharmacological regimen in order to counteract the burden of the disease, and informal caregivers are an important resource for HF patients in managing and coping with their disease. Few studies have examined the lived experience of these caregivers with a rigorous phenomenological approach, and none have been conducted in Italy., Aim: To describe the lived experience of the caregivers of HF patients., Methods: A hermeneutic phenomenological method was used. Caregivers were enrolled in a HF clinic in central Italy. Interviews were analysed using a phenomenological approach. Credibility, dependability, confirmability and transferability were adopted in order to strengthen trustworthiness., Findings: Thirty HF caregivers (mean age: 53 years) were enrolled. Of these, 63% of the caregivers were female and 80% were patients' spouses or children. Six themes emerged: (1) fear and worry related to the illness; (2) life changes and restrictions; (3) burden due to caregiving; (4) uncertainty about illness management; (5) helping patients to cope with the illness; and (6) love and affection towards the patient., Conclusion: The findings of our study may help providers to guide interventions for HF caregivers. Providers should be supportive of caregivers and provide them with education in order to reduce their fears and worries about the illness and to handle the course of HF and its symptoms. An empathetic and practical approach with caregivers that considers the patient-caregiver relationship may help caregivers to cope with the changes and restrictions that caregiving brings to their lives and to reduce their burden.

Well-prepared informal caregivers play an important role in heart failure (HF) care, so an instrument to evaluate their preparedness to care is important. To date, HF caregiver preparedness has been rarely investigated quantitatively. The Caregiver Preparedness Scale (CPS) has been used in other chronic condition populations, but its psychometric characteristics have never been tested in HF caregivers. The purpose of this study was to test the validity and reliability of the 8-item CPS in HF caregivers. In a convenience sample of 317 HF caregivers (72.4% female, mean age 54), we tested the CPS' factorial structure with confirmatory factor analysis (CFA) and its concurrent validity with the Caregiver Contribution to Self-Care of HF Index (CC-SCHFI), and the Hospital Anxiety and Depression Scale (HADS). We also tested CPS' reliability with composite reliability indicators, Cronbach's alpha, factor score determinacy coefficient, and intraclass correlation coefficient (ICC). The CFA for a one-factor model resulted in supportive fit indices (e.g., comparative fit index .97). Significant correlations (p < .05) of the CPS with both the CC-SCHFI and the HADS supported concurrent validity. The composite reliability index, Cronbach's alpha, factor score determinacy coefficient, and ICC were .89, .91, .96, .91, respectively, supporting reliability. Our study provides evidence that the CPS is a valid and reliable instrument to measure HF caregiver preparedness, enabling clinicians, and researchers to target specific interventions to HF caregivers., (© 2017 Wiley Periodicals, Inc.)

Lab-on-a-Chip (LoC) devices are extremely promising in that they enable diagnostic functions at the point-of-care. Within this scope, an important goal is to design imaging schemes that can be used out of the laboratory. In this paper, we introduce and test a pocket holographic slide that allows digital holography microscopy to be performed without an interferometer setup. Instead, a commercial off-the-shelf plastic chip is engineered and functionalized with this aim. The microfluidic chip is endowed with micro-optics, that is, a diffraction grating and polymeric lenses, to build an interferometer directly on the chip, avoiding the need for a reference arm and external bulky optical components. Thanks to the single-beam scheme, the system is completely integrated and robust against vibrations, sharing the useful features of any common path interferometer. Hence, it becomes possible to bring holographic functionalities out of the lab, moving complexity from the external optical apparatus to the chip itself. Label-free imaging and quantitative phase contrast mapping of live samples are demonstrated, along with flexible refocusing capabilities. Thus, a liquid volume can be analyzed in one single shot with no need for mechanical scanning systems., Competing Interests: The authors declare no conflict of interest.

The study of cell adhesion contacts is pivotal to understand cell mechanics and interaction at substrates or chemical and physical stimuli. We designed and built a HoloTIR microscope for label-free quantitative phase imaging of total internal reflection. Here we show for the first time that HoloTIR is a good choice for label-free study of focal contacts and of cell/substrate interaction as its sensitivity is enhanced in comparison with standard TIR microscopy. Finally, the simplicity of implementation and relative low cost, due to the requirement of less optical components, make HoloTIR a reasonable alternative, or even an addition, to TIRF microscopy for mapping cell/substratum topography. As a proof of concept, we studied the formation of focal contacts of fibroblasts on three substrates with different levels of affinity for cell adhesion., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In the current trend of miniaturization and simplification of imaging flow cytometry, Lab-on-a-Chip (LoC) microfluidic devices represent an innovative and cost-effective solution. In this framework, we propose for the first time a novel platform based on the compactness of a holographic microscope slide (HMS) in combination with the new computational features of space-time digital holography (STDH) that uses a 1D linear sensor array (LSA) instead of 2D CCD or CMOS cameras to respond to real diagnostic needs. In this LoC platform, computational methods, holography, and microfluidics are intertwined in order to provide an imaging system with a reduced amount of optical components and capability to achieve reliable cell counting even in the absence of very accurate flow control. STDH exploits the sample motion into the microfluidic channel to obtain an unlimited field-of-view along the flow direction, independent of the magnification factor. Furthermore, numerical refocusing typical of a holographic modality allows imaging and visualization of the entire volume of the channel, thus avoiding loss of information due to the limited depth of focus of standard microscopes. Consequently, we believe that this platform could open new perspectives for enhancing the throughput by 3D volumetric imaging.

Background: A better understanding of caregiver burden and its determinants is essential to support caregivers. Many instruments have been developed to measure caregiver burden in various illness contexts, but few have been psychometrically tested for caregivers of heart failure patients., Aims: The aim of this study was to test the validity (factorial and concurrent validity) and reliability (internal consistency) of the caregiver burden inventory (CBI) in a cohort of caregivers of heart failure patients., Methods: This was a secondary analysis from a cross-sectional study on heart failure patients and their caregivers enrolled from various Italian outpatient centres. The factorial validity of the CBI was tested with confirmatory factor analysis, and concurrent validity was tested correlating CBI scores with the short form-12 health survey scores. The internal consistency reliability was assessed with Cronbach's alpha., Results: In total, 505 caregivers of heart failure patients (52.2% women, mean age 56.59±14.9 years) were enrolled. Confirmatory factor analyses confirmed the original five-factor model: time-dependence, developmental, physical, social and emotional burden. This model fits the data better than the single-factor model, and the dimensions showed high internal consistency reliability (Cronbach's alpha 0.91 for time-dependence burden, 0.92 for developmental burden, 0.88 for physical burden, 0.89 for social burden and 0.93 for emotional burden; 0.96 for the total score of burden)., Conclusion: The CBI proved to be a good multidimensional instrument for evaluating the burden in caregivers of heart failure patients and can be used in clinical practice and research. This tool can be considered to tailor interventions aimed at improving caregiver outcomes.

The integration of digital holography (DH) imaging and the acoustic manipulation of micro-particles in a microfluidic environment is investigated. The ability of DH to provide efficient 3D tracking of particles inside a microfluidic channel is exploited to measure the position of multiple objects moving under the effect of stationary ultrasound pressure fields. The axial displacement provides a direct verification of the numerically computed positions of the standing wave's node, while the particles' transversal movement highlights the presence of nodes in the planar direction. Moreover, DH is used to follow the aggregation dynamics of trapped spheres in such nodes by using aggregation rate metrics.

Aims: Heart Failure (HF) self-care improves patient outcomes but trials designed to improve HF self-care have shown inconsistent results. Interventions may be more effective in improving self-care if they mobilize support from providers, promote self-efficacy, increase understanding of HF, increase the family involvement, and are individualized. All of these elements are emphasized in motivational interviewing (MI); few trials have been conducted using MI in HF patients and rarely have caregivers been involved in MI interventions. The aim of this study will be to evaluate if MI improves self-care maintenance in HF patients, and to determine if MI improves the following secondary outcomes: a) in HF patients: self-care management, self-care confidence, symptom perception, quality of life, anxiety/depression, cognition, sleep quality, mutuality with caregiver, hospitalizations, use of emergency services, and mortality; b) in caregivers: caregiver contribution to self-care, quality of life, anxiety/depression, sleep, mutuality with patient, preparedness, and social support., Methods: A three-arm randomized controlled trial will be conducted in a sample of 240 HF patients and caregivers. Patients and caregivers will be randomized to the following arms: 1) MI intervention to patients only; 2) MI intervention to patients and caregivers; 3) standard of care to patients and caregivers. The primary outcome will be measured in patients 3months after enrollment. Primary and secondary outcomes also will be evaluated 6, 9 and 12months after enrollment., Conclusion: This study will contribute to understand if MI provided to patients and caregivers can improve self-care. Because HF is rising in prevalence, findings can be useful to reduce the burden of the disease., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Self-care is important in heart failure (HF) treatment, but patients may have difficulties and be inconsistent in its performance. Inconsistencies in self-care behaviors may mirror patterns of self-care in HF patients that are worth identifying to provide interventions tailored to patients., Objectives: The aims of this study are to identify clusters of HF patients in relation to self-care behaviors and to examine and compare the profile of each HF patient cluster considering the patient's sociodemographics, clinical variables, quality of life, and hospitalizations., Methods: This was a secondary analysis of data from a cross-sectional study in which we enrolled 1192 HF patients across Italy. A cluster analysis was used to identify clusters of patients based on the European Heart Failure Self-care Behaviour Scale factor scores. Analysis of variance and χ test were used to examine the characteristics of each cluster., Results: Patients were 72.4 years old on average, and 58% were men. Four clusters of patients were identified: (1) high consistent adherence with high consulting behaviors, characterized by younger patients, with higher formal education and higher income, less clinically compromised, with the best physical and mental quality of life (QOL) and lowest hospitalization rates; (2) low consistent adherence with low consulting behaviors, characterized mainly by male patients, with lower formal education and lowest income, more clinically compromised, and worse mental QOL; (3) inconsistent adherence with low consulting behaviors, characterized by patients who were less likely to have a caregiver, with the longest illness duration, the highest number of prescribed medications, and the best mental QOL; (4) and inconsistent adherence with high consulting behaviors, characterized by patients who were mostly female, with lower formal education, worst cognitive impairment, worst physical and mental QOL, and higher hospitalization rates., Conclusion: The 4 clusters identified in this study and their associated characteristics could be used to tailor interventions aimed at improving self-care behaviors in HF patients.

Long-IR wavelength is the best option for capturing digital holograms of large-size, real-world objects. However, the coherent noise level in a long-IR hologram is by far larger than that of a visible wavelength recording, thus resulting in a poor quality of both numerical and optical reconstructions. In this Letter, we show how such coherent noise can be efficiently suppressed by employing an optical scanning multi-look approach, in combination with 3D block matching numerical filtering. Results demonstrate the possibility to obtain near noise-free numerical reconstructions of IR digital holograms of large-size objects, while preserving resolution. We applied this method to the holograms of a rotating statuette. It will be shown that a remarkable contrast enhancement is achievable along with the recovery of object details that otherwise would be lost because of large speckle grains intrinsically due to the source coherence.

Background: Self-care is vital for patients with heart failure to maintain health and quality of life, and it is even more vital for those who are also affected by diabetes mellitus, since they are at higher risk of worse outcomes. The literature is unclear on the influence of diabetes on heart failure self-care as well as on the influence of socio-demographic and clinical factors on self-care., Objectives: (1) To compare self-care maintenance, self-care management and self-care confidence of patients with heart failure and diabetes versus those heart failure patients without diabetes; (2) to estimate if the presence of diabetes influences self-care maintenance, self-care management and self-care confidence of heart failure patients; (3) to identify socio-demographic and clinical determinants of self-care maintenance, self-care management and self-care confidence in patients with heart failure and diabetes., Design: Secondary analysis of data from a multicentre cross-sectional study., Setting: Outpatient clinics from 29 Italian provinces., Participants: 1192 adults with confirmed diagnosis of heart failure., Methods: Socio-demographic and clinical data were abstracted from patients' medical records. Self-care maintenance, self-care management and self-care confidence were measured with the Self-Care of Heart Failure Index Version 6.2; each scale has a standardized score from 0 to 100, where a score <70 indicates inadequate self-care. Multiple linear regression analyses were performed., Results: Of 1192 heart failure patients, 379 (31.8%) had diabetes. In these 379, heart failure self-care behaviours were suboptimal (means range from 53.2 to 55.6). No statistically significant differences were found in any of the three self-care measures in heart failure patients with and without diabetes. The presence of diabetes did not influence self-care maintenance (p=0.12), self-care management (p=0.21) or self-care confidence (p=0.51). Age (p=0.04), number of medications (p=0.01), presence of a caregiver (p=0.04), family income (p=0.009) and self-care confidence (p<0.001) were determinants of self-care maintenance. Gender (p=0.01), number of medications (p=0.004) and self-care confidence (p<0.001) were significant determinants of self-care management. Number of medications (p=0.002) and cognitive function (p<0.001) were determinants of self-care confidence., Conclusions: Self-care was poor in heart failure patients with diabetes mellitus. This population needs more intensive interventions to improve self-care. Determinants of self-care in heart failure patients with diabetes mellitus should be systematically assessed by clinicians to identify patients at risk of inadequate self-care., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

One of the main drawbacks of Digital Holography (DH) is the coherent nature of the light source, which severely corrupts the quality of holographic reconstructions. Although numerous techniques to reduce noise in DH have provided good results, holographic noise suppression remains a challenging task. We propose a novel framework that combines the concepts of encoding multiple uncorrelated digital holograms, block grouping and collaborative filtering to achieve quasi noise-free DH reconstructions. The optimized joint action of these different image-denoising methods permits the removal of up to 98% of the noise while preserving the image contrast. The resulting quality of the hologram reconstructions is comparable to the quality achievable with non-coherent techniques and far beyond the current state of art in DH. Experimental validation is provided for both single-wavelength and multi-wavelength DH, and a comparison with the most used holographic denoising methods is performed.

Background: Although a number of studies have been conducted on patients with Heart Failure (HF), they have not given a rigorous comprehensive description of what it is like to live with HF. The objective of this study was to describe the lived experience of adults with HF., Study Design: A hermeneutic phenomenological design was used., Methods: Cohen's method was used to conduct the study. Thirty HF patients were enrolled between February and July 2014 from an outpatient cardiovascular clinic in Tuscany, Italy. Phenomenological interviews took place at patients' homes, and the investigators analyzed verbatim transcripts. Once data saturation was achieved, to ensure data trustworthiness, participants were asked to confirm all the extracted themes. Atals.ti vers.7 was used for data analysis., Results: The patients were mostly male (67%) with a mean age of 71 (SD 9.15) and an age range of 48-86. Seven themes emerged from the phenomenological analysis: 1) important life changes; 2) social isolation caused by the illness; 3) anger and resignation associated with the disease; 4) relief from spirituality; 5) will to live; 6) uncertainty about the future and 7) the inescapability of disease and death., Conclusions: The meaning that patients attribute to their lived experience helps to create their needs, which are important to direct care. Family support and religious beliefs are an important source for HF patients to better manage their fears and cope with the future. Findings of this study provide nurses with a comprehensive description of what it is like to live with HF, which can be useful in helping to meet patients' needs more effectively and in tailoring interventions.

. Mixed methods designs: an innovative methodological approach for nursing research. The mixed method research designs (MM) combine qualitative and quantitative approaches in the research process, in a single study or series of studies. Their use can provide a wider understanding of multifaceted phenomena. This article presents a general overview of the structure and design of MM to spread this approach in the Italian nursing research community. The MM designs most commonly used in the nursing field are the convergent parallel design, the sequential explanatory design, the exploratory sequential design and the embedded design. For each method a research example is presented. The use of MM can be an added value to improve clinical practices as, through the integration of qualitative and quantitative methods, researchers can better assess complex phenomena typical of nursing.

We report a novel method for direct printing of viscous polymers based on a pyro-electrohydrodynamic repulsion system capable of overcoming limitations on the material type, geometry and thickness of the receiving substrate. In fact, the results demonstrate that high viscosity polymers can be easily manipulated for optical functionalizing of lab-on-a-chip devices through demonstration of direct printing of polymer microlenses onto microfluidic chips and optical fibre terminations. The present system has great potential for applications from biomolecules to nano-electronics. Moreover, in order to prove the effectiveness of the system, the optical performance of such microlenses has been characterized by testing their imaging capabilities when the fibroblast cells were allowed to flow inside the microfluidic channel, showing one of their possible applications on-board a LoC platform.

Simple and effective imaging strategies are of utmost interest for applications on a lab-on-chip scale. In fact, the majority of diagnostic tools for medical as well as biotechnological studies still employ image-based approaches. Having onboard the chip a compact but powerful imaging apparatus with multiple imaging capabilities, such as 3D dynamic focusing along the optical axis, unlimited field of view (FoV) and double outputs, namely, intensity and quantitative phase-contrast maps of biological objects, is of extreme importance for the next generation of Lab-on-a-Chip (LoC) devices. Here we present a coherent 3D microscopy approach with a holographic modality that is specifically suitable for studying biological samples while they simply flow along microfluidic paths. The LoC device is equipped with a compact linear array detector to capture and generate a new conceptual type of a digital hologram in the space-time domain, named here as Space-Time Digital Hologram (STDH). The reported results show that the method is a promising diagnostic tool for optofluidic investigations of biological specimens.

We designed, constructed and tested a holographic surface plasmon resonance (HoloSPR) objective-based microscope for simultaneous amplitude-contrast and phase-contrast surface plasmon resonance imaging (SPRi). SPRi is a widely spread tool for label-free detection of changes in refractive index and concentration, as well as mapping of thin films. Currently, most of the SPR sensors rely on the detection of amplitude or phase changes of light. Despite the high sensitivities achieved so far, each technique alone has a limited detection range with optimal sensitivity. Here we use a high numerical aperture objective that avoids all the limitations due to the use of a prism-based configuration, yielding highly magnified and distortion-free images. Holographic reconstructions of SPR images and real-time kinetic measurements are presented to show the capability of HoloSPR to provide a versatile imaging method for high-throughput SPR detection complementary to conventional SPR techniques.

We show here that live e-coli bacterial culture, thanks to the self-propelling feature, can significantly reduce the coherent noise. In fact, the typical self-propelled drive of such microorganisms provides enough time diversity in speckle patterns. Optical properties of a bacteria suspension have been investigated and analyzed thus showing that it behaves as a quite good optical speckle decorrelation device. Samples with different bacteria densities have been studied. The decorrelation effect has been demonstrated by probing the imaging performance in through transmission in coherent microscope configuration.

In digital holography (DH) a mixture of speckle and incoherent additive noise, which appears in numerical as well as in optical reconstruction, typically degrades the information of the object wavefront. Several methods have been proposed in order to suppress the noise contributions during recording or even during the reconstruction steps. Many of them are based on the incoherent combination of multiple holographic reconstructions achieving remarkable improvement, but only in the numerical reconstruction i.e. visualization on a pc monitor. So far, it has not been shown the direct synthesis of a digital hologram which provides the denoised optical reconstruction. Here, we propose a new effective method for encoding in a single complex wavefront the contribution of multiple incoherent reconstructions, thus allowing to obtain a single synthetic digital hologram that show significant speckle-reduction when optically projected by a Spatial Light Modulator (SLM).

We investigate the spatio-temporal scanning of a single-pixel row for building up synthetic interferograms or digital holograms, shifted each other of a desired phase step. This unusual recording modality exploits the object movement to synthesize interferograms with extended Field of View and improved noise contrast. We report the theoretical formulation of the synthetizing recording process and experimental evidence of various cases demonstrating quantitative phase retrieval by adopting this intrinsic phase-shifting procedure. The proposed method could be particularly suited in all cases where the object shift is an intrinsic feature of the investigated system, as e.g. in microfluidics imaging.

Several automatic approaches have been proposed in the past to compute the refocus distance in digital holography (DH). However most of them are based on a maximization or minimization of a suitable amplitude image contrast measure, regarded as a function of the reconstruction distance parameter. Here we show that, by using the sparsity measure coefficient regarded as a refocusing criterion in the holographic reconstruction, it is possible to recover the focus plane and, at the same time, establish the degree of sparsity of digital holograms, when samples of the diffraction Fresnel propagation integral are used as a sparse signal representation. We employ a sparsity measurement coefficient known as Gini's index thus showing for the first time, to the best of our knowledge, its application in DH, as an effective refocusing criterion. Demonstration is provided for different holographic configurations (i.e., lens and lensless apparatus) and for completely different objects (i.e., a thin pure phase microscopic object as an in vitro cell, and macroscopic puppets) preparation.

Imaging through turbid media is a challenging topic. A liquid is considered turbid when dispersed particles provoke strong light scattering, thus destroying the image formation by any standard optical system. Generally, colloidal solutions belong to the class of turbid media since dispersed particles have dimensions ranging between 0.2 μm and 2 μm. However, in microfluidics, another relevant issue has to be considered in the case of flowing liquid made of a multitude of occluding objects, e.g. red blood cells (RBCs) flowing in veins. In such a case instead of severe scattering processes unpredictable phase delays occur resulting in a wavefront distortion, thus disturbing or even hindering the image formation of objects behind such obstructing layer. In fact RBCs can be considered to be thin transparent phase objects. Here we show that sharp amplitude imaging and phase-contrast mapping of cells hidden behind biological occluding objects, namely RBCs, is possible in harsh noise conditions and with a large field-of view by Multi-Look Digital Holography microscopy (ML-DH). Noteworthy, we demonstrate that ML-DH benefits from the presence of the RBCs, providing enhancement in terms of numerical resolution and noise suppression thus obtaining images whose quality is higher than the quality achievable in the case of a liquid without occlusive objects.

Total Internal Reflection Digital Holographic Microscopy (TIRDHM) is recognized to be a powerful tool for retrieving quantitative phase images of cell-substrate interfaces, adhesions, and tissue structures close to the prism surface. In this Letter, we develop an improved TIRDHM system, taking advantage of a refractive index mismatch between the prism and the sample substrate, to allow phase-shifting DH with just a single-beam interferometric configuration. Instead of the traditional off-axis method, phase-shift method is used to retrieve amplitude and phase images in coherent light and TIR modality. Essentially, the substrate-prism interface acts like a beam splitter generating a reference beam, where the phase-shift dependence on the incident angle is exploited in this common-path configuration. With the aim to demonstrate the technique's validity, some experiments are performed to establish the advantage of this compact and simple configuration, in which the reference arm in the setup is avoided.

We tackle the problem of information recovery and imaging through scattering microfluidic chips by means of digital holography (DH). In many cases the chip can become opalescent due to residual deposits settling down the inner channel faces, biofilm formation, scattering particle uptake by the channel cladding or its damaging by corrosive substances, or even by condensing effect on the exterior channels walls. In these cases white-light imaging is severely degraded and no information is obtainable at all about the flowing samples. Here we investigate the problem of counting and estimating velocity of cells flowing inside a scattering chip. Moreover we propose and test a method based on the recording of multiple digital holograms to retrieve improved phase-contrast images despite the strong scattering effect. This method helps, thanks to DH, to recover information which, otherwise, would be completely lost.

In this Letter we propose a method to enhance the limited depth of field (DOF) in optical imaging systems, through digital holography. The proposed approach is based on the introduction of a cubic phase plate into the diffraction integral, analogous to what occurs in white-light imaging systems. By this approach we show that it is possible to improve the DOF and to recover the extended focus image of a tilted object in a single reconstruction step. Moreover, we demonstrate the possibility of obtaining well-focused biological cells flowing into a tilted microfluidic channel.

The ability to see behind flames is a key challenge for the industrial field and particularly for the safety field. Development of new technologies to detect live people through smoke and flames in fire scenes is an extremely desirable goal since it can save human lives. The latest technologies, including equipment adopted by fire departments, use infrared bolometers for infrared digital cameras that allow users to see through smoke. However, such detectors are blinded by flame-emitted radiation. Here we show a completely different approach that makes use of lensless digital holography technology in the infrared range for successful imaging through smoke and flames. Notably, we demonstrate that digital holography with a cw laser allows the recording of dynamic human-size targets. In this work, easy detection of live, moving people is achieved through both smoke and flames, thus demonstrating the capability of digital holography at 10.6 μm.

We propose a denoising method for digital holography mod 2π wrapped phase map by using an adaptation of the SPArsity DEnoising of Digital Holograms (SPADEDH) algorithm. SPADEDH is a l(1) minimization algorithm able to suppress the noise components on digital holograms without any prior knowledge or estimation about the statistics of noise. We test our algorithm with either general numerical simulated wrapped phase, quantifying the performance with different efficiency parameters and comparing it with two popular denoising strategies, i.e., median and Gaussian filters, and specific experimental tests, by focusing our attention on long-sequence wrapped quantitative phase maps (QPMs) of in vitro cells, which aim to have uncorrupted QPMs. In addition, we prove that the proposed algorithm can be used as a helper for the typical local phase unwrapping algorithms.

Holographic imaging may become severely degraded by a mixture of speckle and incoherent additive noise. Bayesian approaches reduce the incoherent noise, but prior information is needed on the noise statistics. With no prior knowledge, one-shot reduction of noise is a highly desirable goal, as the recording process is simplified and made faster. Indeed, neither multiple acquisitions nor a complex setup are needed. So far, this result has been achieved at the cost of a deterministic resolution loss. Here we propose a fast non-Bayesian denoising method that avoids this trade-off by means of a numerical synthesis of a moving diffuser. In this way, only one single hologram is required as multiple uncorrelated reconstructions are provided by random complementary resampling masks. Experiments show a significant incoherent noise reduction, close to the theoretical improvement bound, resulting in image-contrast improvement. At the same time, we preserve the resolution of the unprocessed image.

Digital Holography (DH) in microscopic configuration is a powerful tool for the imaging of micro-objects contained into a three dimensional (3D) volume, by a single-shot image acquisition. Many studies report on the ability of DH to track particle, microorganism and cells in 3D. However, very few investigations are performed with objects that change severely their morphology during the observation period. Here we study DH as a tool for 3D tracking an osteosarcoma cell line for which extensive changes in cell morphology are associated to cell motion. Due to the great unpredictable morphological change, retrieving cell's position in 3D can become a complicated issue. We investigate and discuss in this paper how the tridimensional position can be affected by the continuous change of the cells. Moreover we propose and test some strategies to afford the problems and compare it with others approaches. Finally, results on the 3D tracking and comments are reported and illustrated.

Recently it has been demonstrated that digital holography is a powerful means allowing imaging of both amplitude and phase objects in turbid flowing media. However, in quasi-static turbid microfluidics, multiple scattering contributions through the colloids superimpose coherently to the recording device, resulting in speckle noise and hindering a clear vision of the objects. In this Letter we exploit the Brownian motion of the colloidal particles to get multiple uncorrelated holograms, and we combine them to reduce the speckle contrast. In this way we get a multi-look gain without losing image resolution.

We show that sharp imaging and quantitative phase-contrast microcopy is possible in microfluidics in flowing turbid media by digital holography. In fact, in flowing liquids with suspended colloidal particles, clear vision is hindered and cannot be recovered by any other microscopic imaging technique. On the contrary, using digital holography, clear imaging is possible thanks to the Doppler frequency shift experienced by the photons scattered by the flowing colloidal particles, which do not contribute to the interference process, i.e. the recorded hologram. The method is illustrated and imaging results are demonstrated for pure phase objects, i.e. biological cells in microfluidic channels.

A circular holographic display that consists of phase-only spatial light modulators is used to reconstruct images in visible light from digital holograms recorded under infrared (10.6 μm) illumination. The reconstruction yields a holographic digital video display of a three-dimensional ghostlike image of an object floating in space where observers can move and rotate around it.

A method based on spatial transformations of multiwavelength digital holograms and the correlation matching of their numerical reconstructions is proposed, with the aim to improve superimposition of different color reconstructed images. This method is based on an adaptive affine transform of the hologram that permits management of the physical parameters of numerical reconstruction. In addition, we present a procedure to synthesize a single digital hologram in which three different colors are multiplexed. The optical reconstruction of the synthetic hologram by a spatial light modulator at one wavelength allows us to display all color features of the object, avoiding loss of details.

A major issue so far for digital holography is the low spatial resolution generally achieved. The numerical aperture is limited by the area of currently available detectors, such as CCD sensors, which is significantly lower than that of a holographic plate. This is an even more severe constraint when IR sensors such as microbolometers are taken into account. In order to increase the numerical aperture of such systems, we developed an automatic technique which is capable of recording several holograms and of stitching them together, obtaining a digital hologram with a synthetic but larger numerical aperture. In this way we show that more detail can be resolved and a wider parallax angle can be achieved. The method is demonstrated for visible as well IR digital holography, recording and displaying large size objects.