Synthesis of Silver, Gold, and Platinum Doped Zinc Oxide Nanoparticles by Pulsed Laser Ablation in Water

In this paper, we propose a simple two-step method for the synthesis of Ag, Au, and Pt-doped ZnO nanoparticles. The method is based on the fabrication of targets using the pulsed laser deposition (PLD) technique where thin layers of metals (Ag, Pt, Au) have been deposited on a metal-oxide bulk substrate (ZnO). Such formed structures were used as a target for the production of doped nanoparticles (ZnO: Ag, ZnO: Au, and ZnO: Pt) by laser ablation in water. The influence of Ag, Au, and Pt doping on the optical properties, structure and composition, sizing, and morphology was studied using UV-Visible (UV-Vis) and photoluminescence (PL) spectroscopies, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), respectively. The band-gap energy decreased to 3.06, 3.08, and 3.15 for silver, gold, and platinum-doped ZnO compared to the pure ZnO (3.2 eV). PL spectra showed a decrease in the recombination rate of the electrons and holes in the case of doped ZnO. SEM, TEM, and AFM images showed spherical-shaped nanoparticles with a relatively smooth surface. The XRD patterns confirm that Ag, Au, and Pt were well incorporated inside the ZnO lattice and maintained a hexagonal wurtzite structure. This work could provide a new way for synthesizing various doped materials.

Analytical Model for Determination of Size-Distribution of Colloidal Silver Nanoparticles from Surface Plasmon Resonance Wavelength and Dielectric Functions

In this work it is shown that the size of silver nanoparticles in a colloidal solution can be determined only from the wavelength of the surface plasmon resonance and material and medium dielectric functions. The size dependence of dielectric functions of silver nanoparticles becomes noticeable in nanoparticles which are smaller than 30 nm in size, which is in accordance with Mie scattering theory applicability. The novelty of this work is in the development of an analytical model for the determination of the size of silver nanoparticles derived from applying shift functions to the UV-Vis spectra, resulting in well-known characteristic diameters of log-normal size distribution function. The purpose of these shift functions is the reconstruction of experimental UV-Vis spectra from simulated ones based on the Beer-Lambert law and log-normal distribution function in order to find the mode diameters of colloidal silver nanoparticles. The introduction of Lagrangian analogue of extinction cross section explains the redshift constant characteristic for given nanoparticle material and the size distribution of nanoparticles. Therefore, the size determination of colloidal silver nanoparticles is possible only through UV-Vis spectroscopy.

Fitting Procedure to Reconstruct the Size Distribution and the Concentration of Silver Colloidal Nanoparticles from UV-Vis Spectra

In this work, a complete fitting procedure of UV-Vis spectra of silver nanoparticles in colloidal solutions is reported. The fitting function, based on the Beer-Lambert law, Mie theory, and log-normal probability distribution of nanoparticles' sizes, is developed and confirmed by 33 different independent measurements. In order to validate the accuracy of the function's behavior on different spectra, freely accessible measurements were used, proving that the fitting function works independently of the method of their production-laser or chemical synthesis of nanoparticles. The developed fitting function is, to the best of our knowledge, novel and not based on any conventional spectral analysis approaches like the Mie-Gans procedure. Furthermore, since fitted parameters are all physical, it allows determination of the mode diameter of nanoparticles as well as the standard deviation of the log-normal distribution of sizes. It enables the reconstruction of size distribution of nanoparticles in colloidal solution. Step-by-step derivation of the fitting function is provided with a physical explanation of all parameters. The importance of Lorentzian dependence emerging at the core of Beer-Lambert law is physically discussed and linked to harmonic oscillator behavior of localized surface plasmon resonance of silver nanoparticles in a colloidal solution. Size distribution reconstruction from fitted parameters according to a log-normal distribution function is provided and a concentration calculation is presented.

Prospective Evaluation of Cognitive Health and Related Factors in Elderly at Risk for Developing Alzheimer's Dementia: A Longitudinal Cohort Study

BACKGROUND

The CHARIOT PRO Main study is a prospective, non-interventional study evaluating cognitive trajectories in participants at the preclinical stage of Alzheimer's disease (AD) classified by risk levels for developing mild cognitive impairment due to AD (MCI-AD).

OBJECTIVES

The study aimed to characterize factors and markers influencing cognitive and functional progression among individuals at-risk for developing MCI-AD, and examine data for more precise predictors of cognitive change, particularly in relation to APOE ε4 subgroup.

DESIGN

This single-site study was conducted at the Imperial College London (ICL) in the United Kingdom. Participants 60 to 85 years of age were classified as high, medium (amnestic or non-amnestic) or low risk for developing MCI-AD based on RBANS z-scores. A series of clinical outcome assessments (COAs) on factors influencing baseline cognitive changes were collected in each of the instrument categories of cognition, lifestyle exposure, mood, and sleep. Data collection was planned to occur every 6 months for 48 months, however the median follow-up time was 18.1 months due to early termination of study by the sponsor.

RESULTS

987 participants were screened, among them 690 participants were actively followed-up post baseline, of whom 165 (23.9%) were APOE ε4 carriers; with at least one copy of the allele. The mean age was 68.73 years, 94.6% were white, 57.4% were female, and 34.8% had a Family History of Dementia with a somewhat larger percentage in the APOE ε4 carrier group (42.4%) compared to the non-carrier group (32.4%). Over half of the participants were married and 53% had a Bachelor's or higher degree. Most frequently, safety events typical for this population consisted of upper respiratory tract infection (10.4%), falls (5.2%), hypertension (3.5%) and back pain (3.0%). Conclusion (clinical relevance): AD-related measures collected during the CHARIOT PRO Main study will allow identification and evaluation of AD risk factors and markers associated with cognitive performance from the pre-clinical stage. Evaluating the psycho-biological characteristics of these pre-symptomatic individuals in relation to their natural neurocognitive trajectories will enhance current understanding on determinants of the initial signs of cognitive changes linked to AD.

Eczema apps conformance with clinical guidelines: a systematic assessment of functions, tools and content

BACKGROUND

Eczema is a prevalent complex skin condition requiring active disease monitoring and personalized education. No studies have assessed the quality of apps that aim to support eczema self-management.

OBJECTIVES

To evaluate the quality and comprehensiveness of English, Chinese and Spanish self-management eczema smartphone apps for patients and/or their caregivers.

METHODS

A systematic assessment of eczema apps from July 2018 to November 2018. The assessment criteria were based on conformance with international eczema guidelines. The following domains were assessed: consistency and comprehensiveness of eczema-specific educational information; quality and comprehensiveness of eczema-specific tracking functions; compliance with health information best practice principles.

RESULTS

In total, 98 apps were assessed: 82 (84%) provided educational information; 38 (39%) tracking functions; and 13 (13%) both. We found that 34% (28/82) of apps provided misleading information, particularly regarding aspects of treatment and disease progression of eczema. Only 15% (12/82) provided international guideline supported information on pharmacological therapies and 16% (13/82) on nonpharmacological therapies. Among 38 apps with a tracking function, 82% (31/38) measured specific symptoms, disease severity or current skin condition and 89% (34/38) helped users to record medication usage including application of topicals. Environmental or dietary allergens were recorded by 34% (13/38). None of the included apps complied with all criteria for educational information, tracking functions or health information principles.

CONCLUSIONS

Eczema apps have not yet reached their potential. The large variance in quality of eczema apps highlights the need for quality assurance mechanisms for health apps and guidance for clinicians that would enable them to make personalized recommendations for patients and caregivers. What's already known about this topic? There is limited information about the quality of eczema self-management smartphone apps on the global market. What does this study add? This systematic assessment evaluated all English, Chinese and Spanish language apps that support eczema self-management. The majority did not conform with information in guidelines and insufficiently support evidence-based self-management. The large variance in the quality of eczema apps highlights the need for mechanisms to ensure app quality and to guide personalized app selection for patients, caregivers and doctors.

Telehealth requires expansion of physicians' communication competencies training

We are in the midst of transformation of health systems where remote consulting (via video, telephone, email, and mobile messaging) is soon to become the dominant mode of consultation. Most of the literature on telehealth omits mentioning the need for telehealth communication competencies. Yet evidence base has been growing about how critical this training is - whether from clinical communication research or litigation claims analysis. In this article, we are calling for an urgent expansion of communication skills curricula to encompass these new telehealth domains from medical schools, specialty trainings to CMEs.

Light therapies for acne: abridged Cochrane systematic review including GRADE assessments

We undertook a Cochrane review of randomized controlled trials (RCTs) evaluating the effects of light-based interventions for acne vulgaris. We searched the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, ISI Web of Science and grey literature sources (September 2015). We used the Grading of Recommendations Assessment, Development and Evaluation Working Group approach to assess the quality of evidence (QoE). We included 71 RCTs (4211 participants, median sample size 31). Results from a single study (n = 266, low QoE) showed little or no difference in effectiveness on participants' assessment of improvement between 20% aminolaevulinic acid (ALA) photodynamic therapy (PDT), activated by blue light, vs. vehicle plus blue light, whereas another study (n = 180) comparing ALA-PDT (red light) concentrations showed that 20% ALA-PDT was no more effective than 15% ALA-PDT but better than 10% and 5% ALA-PDT. Pooled data from three studies (n = 360, moderate QoE) showed that methyl aminolaevulinate PDT, activated by red light, had a similar effect on changes in lesion counts vs. placebo cream with red light. Several studies compared yellow light with placebo or no treatment, infrared light with no treatment, gold microparticle suspension with vehicle and clindamycin/benzoyl peroxide (C/BPO) combined with pulsed dye laser with C/BPO alone. None of these showed any clinically significant effects. Most studies reported adverse effects, but inadequately, with scarring reported as absent, and blistering only in studies on intense pulsed light, infrared light and PDT (very low QoE). Carefully planned studies, using standardized outcome measures and common acne treatments as comparators, are needed.

How to monitor patient safety in primary care? Healthcare professionals' views

Objective

To identify patient safety monitoring strategies in primary care.

Design

Open-ended questionnaire survey.

Participants

A total of 113 healthcare professionals returned the survey from a group of 500 who were invited to participate achieving a response rate of 22.6%.

Setting

North-West London, United Kingdom.

Method

A paper-based and equivalent online survey was developed and subjected to multiple stages of piloting. Respondents were asked to suggest strategies for monitoring patient safety in primary care. These monitoring suggestions were then subjected to a content frequency analysis which was conducted by two researchers.

Main Outcome measures

Respondent-derived monitoring strategies.

Results

In total, respondents offered 188 suggestions for monitoring patient safety in primary care. The content analysis revealed that these could be condensed into 24 different future monitoring strategies with varying levels of support. Most commonly, respondents supported the suggestion that patient safety can only be monitored effectively in primary care with greater levels of staffing or with additional resources.

Conclusion

Approximately one-third of all responses were recommendations for strategies which addressed monitoring of the individual in the clinical practice environment (e.g. GP, practice nurse) to improve safety. There was a clear need for more staff and resource set aside to allow and encourage safety monitoring. Respondents recommended the dissemination of specific information for monitoring patient safety such as distributing the lessons of significant event audits amongst GP practices to enable shared learning.

Scope and effectiveness of mobile phone messaging for HIV/AIDS care: a systematic review

The objective of this mixed method systematic review was to assess the scope, effectiveness, acceptability and feasibility of the use of mobile phone messaging for HIV infection prevention, treatment and care. We comprehensively searched the peer-reviewed and grey literature. Two authors independently screened citations, extracted data and assessed study quality of included studies (any research design) focusing on mobile phone messaging interventions for HIV care. We present a narrative overview of the results. Twenty-one studies met the inclusion criteria: three randomized controlled trials, 11 interventional studies using other study designs and seven qualitative or cross-sectional studies. We also found six on-going trials and 21 projects. Five of the on-going trials and all the above mentioned projects took place in low or middle-income countries. Mobile phone messaging was researched for HIV prevention, appointment reminders, HIV testing reminders, medication adherence and for communication between health workers. Of the three randomized controlled trials assessing the use of short message service (SMS) to improve medication adherence, two showed positive results. Other interventional studies did not provide significant results. In conclusion, despite an extensive search we found limited evidence on the effectiveness of mobile phone messaging for HIV care. There is a need to adequately document outcomes and constraints of programs using mobile phone messaging to support HIV care to assess the impact and to focus on best practice.

A systematic review of interventions promoting clinical information retrieval technology (CIRT) adoption by healthcare professionals

PURPOSE

This paper presents the evidence on the effectiveness of interventions promoting the use of clinical information retrieval technologies (CIRTs) by healthcare professionals.

METHODS

We electronically searched articles published between January 1990 and March 2008 using following inclusion criteria: (1) participants were healthcare professionals; (2) specific intervention promoted CIRT adoption; (3) studies were randomised controlled trials, controlled clinical trials, controlled before and after studies or interrupted time series analyses; and (4) they objectively reporting measured outcomes on CIRT use.

RESULTS

We found nine studies focusing on CIRT use. Main outcomes measured were searching skills and/or frequency of use of electronic databases by healthcare professionals. Three studies reported a positive effect of the intervention on CIRT use, one showed a positive impact post-intervention, and four studies failed to demonstrate significant intervention effect. The ninth study examined financial disincentives, and found a significant negative effect of introducing user fees for searching MEDLINE in clinical settings. A meta-analysis showed that educational meetings were the only type of interventions reporting consistent positive effects on CIRT adoption.

CONCLUSION

CIRT is an information and communication technology commonly used in healthcare settings. Interventions promoting CIRT adoption by healthcare professionals have shown some success in improving searching skills and use of electronic databases. However, the effectiveness of these interventions remains uncertain and more rigorous studies are needed.

Patient confidentiality and telephone consultations: time for a password

Although telephone consultations are widely used in the delivery of healthcare, they are vulnerable to breaches of patient confidentiality. Current guidelines on telephone consultations do not address adequately the issue of confidentiality. In this paper, we propose a solution to the

PROBLEM

a password system to control access to patient information. Authorised persons will be offered the option of selecting a password which they will use to validate their request for information over the telephone. This simple yet stringent method of access control should improve security while allowing the continuing evolution of telephone consultations.

Understanding reasons for asthma outpatient (non)-attendance and exploring the role of telephone and e-consulting in facilitating access to care: exploratory qualitative study

OBJECTIVE

To understand factors influencing patients' decisions to attend for outpatient follow up consultations for asthma and to explore patients' attitudes to telephone and email consultations in facilitating access to asthma care.

DESIGN

Exploratory qualitative study using in depth interviews.

SETTING

Hospital outpatient clinic in West London.

PARTICIPANTS

Nineteen patients with moderate to severe asthma (12 "attenders" and 7 "non-attenders").

RESULTS

Patients' main reasons for attending were the wish to improve control over asthma symptoms and a concern not to jeopardise the valued relationship with their doctor. Memory lapses, poor health, and disillusionment with the structure of outpatient care were important factors implicated in non-attendance. The patients were generally sceptical about the suggestion that greater opportunity for telephone consulting might improve access to care. They expressed concerns about the difficulties in effectively communicating through non-face to face media and were worried that clinicians would not be in a position to perform an adequate physical examination over the telephone. Email and text messaging were viewed as potentially useful for sending appointment reminders and sharing clinical information but were not considered to be acceptable alternatives to the face to face clinic encounter.

CONCLUSIONS

Memory lapses, impaired mobility due to poor health, and frustration with outpatient clinic organisation resulting in long waiting times and discontinuity of care are factors that deter patients from attending for hospital asthma assessments. The idea of telephone review assessments was viewed with scepticism by most study subjects. Particular attention should be given to explaining to patients the benefits of telephone consultations, and to seeking their views as to whether they would like to try them out before replacing face to face consultations with them. Email and text messaging may have a role in issuing reminders about imminent appointments.

Interventions for improving patients' trust in doctors and groups of doctors

BACKGROUND

Trust is a fundamental component of the patient-doctor relationship and is associated with increased satisfaction, adherence to treatment, and continuity of care. It is not clear if there are interventions known to be effective in enhancing patient trust in doctors.

OBJECTIVES

To assess the effects of interventions intended to improve a patient's trust in the doctor or a group of doctors.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1 2003), MEDLINE(1966 to week 4 2003), EMBASE (1985 to July 2003), Health Star (1975 to July 2004), PsycINFO (1967 to July 2004), CINAHL (1982 to June 2003), LILACS (1982 to April 2003), African Trials Register (1948 to April 2003), African Health Anthology (1924 to April 2003), Dissertation Abstracts International (1861 to April 2003) and the bibliographies of studies assessed for inclusion. We also searched the bibliographies of studies assessed for inclusion, and contacted researchers active in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs), controlled clinical trials, controlled before and after studies, and interrupted time series studies of interventions (informative, educational, behavioural, organisational) directed at doctors or patients (or carers) where trust was assessed as a primary or secondary outcome.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data.

MAIN RESULTS

Three RCTs, all published in English and set in North American primary care, and involving 1916 participants, were included. There was considerable heterogeneity in terms of aims, format and content of the interventions. One trial of a training intervention for family doctors to improve communication behaviours (20 doctors assessed by 414 patients) showed no effect on trust. The other two interventions were patient focussed. One explored the impact on trust of disclosing physician incentives to patients (n= 918) in a Health Maintenance Organisation (HMO) and showed no diminution in trust. Another investigated the effect of induction visits on new HMO members' (n=564) trust in their HMO doctors. Trust in doctors rose compared with control following the visit for one type of induction visit, the group visit (Trust out of 10 (standard deviation (SD)) was 8.8 (1.5) and 7.1 (2.2), difference 1.7, (95% confidence interval 1.22 to 2.18)). However there were many drop-outs and analysis was not on intention to treat.

AUTHORS' CONCLUSIONS

Overall there remains insufficient evidence to conclude that any intervention may increase or decrease trust in doctors. Further trials are required to explore the impact of policy changes, guidelines and specific doctors' training on patients' trust.

Crosscultural communication in those with airway diseases

Transcultural consultations are becoming commonplace. Such consultations arise because patients from ethnic groups consult doctors, but also because patients consult doctors from other ethnic backgrounds. Such consultations require a cultural awareness and sensitivity which may be particularly necessary when concerning those with respiratory illnesses which are often long-term and about which there may be considerable stigma. The prevalence of respiratory disease can vary between ethnic groups, most noticeably in tuberculosis and smoking; and in diseases such as asthma, health service usage and treatment can vary significantly with ethnicity. Some of this may represent cultural, rather than disease specific differences. Good communication is essential throughout medical practice, but in transcultural consultations it is especially important that the doctor pays appropriate attention to likely patient beliefs and approaches to shared decision making. Usual negotiation regarding goals and outcomes first requires the clinician to understand how a patient's understanding of illness may vary from a traditional western scientific approach. Special attention needs to be paid to the optimal way of using interpreters and more time is often needed for crosscultural consultations. Specific training is necessary for health practitioners to enable them to acquire the skills for crosscultural care and this involves learning about other cultures and an appreciation of how a change in attitude often needs to be incorporated into the clinical approach. Acquiring these skills and understandings to facilitate optimal transcultural consultation enables transfer of these skills to other similar clinical scenarios such as the approach to those with disability. The global burden of long-term respiratory disease, both infectious and noncommunicable, coupled with increased migration and geographical mobility means that a successful crosscultural approach is now a priority area for attention.