The effect of COVID-19 on cancer incidences in the U.S.

Fundamental data analysis assists in the evaluation of critical questions to discern essential facts and elicit formerly invisible evidence. In this article, we provide clarity into a subtle phenomenon observed in cancer incidences throughout the time of the COVID-19 pandemic. We analyzed the cancer incidence data from the American Cancer Society [1]. We partitioned the data into three groups: the pre-COVID-19 years (2017, 2018), during the COVID-19 years (2019, 2020, 2021), and the post-COVID-19 years (2022, 2023). In a novel manner, we applied principal components analysis (PCA), computed the angles between the cancer incidence vectors, and then added lognormal probability concepts in our analysis. Our analytic results revealed that the cancer incidences shifted within each era (pre, during, and post), with a meaningful change in the cancer incidences occurring in 2020, the peak of the COVID-19 era. We defined, computed, and interpreted the exceedance probability for a cancer type to have 1000 incidences in a future year among the breast, cervical, colorectal, uterine corpus, leukemia, lung & bronchus, melanoma, Hodgkin's lymphoma, prostate, and urinary cancers. We also defined, estimated, and illustrated indices for other cancer diagnoses from the vantage point of breast cancer in pre, during, and post-COVID-19 eras. The angle vectors post the COVID-19 were 72% less than pre-pandemic and 28% less than during the pandemic. The movement of cancer vectors was dynamic between these eras, and movement greatly differed by type of cancer. A trend chart of cervical cancer showed statistical anomalies in the years 2019 and 2021. Based on our findings, a few future research directions are pointed out.

Technology alone does not achieve error reduction - a study of handwritten, tick-sheet, ink stamp and electronic medical prescriptions.

BACKGROUND: Technology in the form of electronic record systems and prescriptions have been touted as a potential solution to human error. In South Africa, a middle-income country where health facilities have large variations in technological capacity, prescription errors can be complex and varied. We evaluated different prescribing methods to find if the increased use of technology in prescriptions will assist in reducing error rates. METHODS: A retrospective, non-randomised study compared prescriptions, error rates and types in four hospitals with different prescribing methods: these were handwritten, ink stamp, tick-sheet and electronic prescriptions. A modern human error theory data collection tool was designed which included patient complexity. Cataract surgery was chosen as the single common procedure. RESULTS: One thousand six hundred and sixty-one individual scripts had 1 307 prescription errors. Increasing patient complexity was not an indicator of error rate. Handwritten and tick-sheet prescriptions had the fewest errors (49% and 51%, respectively). Electronic (96%) and ink stamp scripts (101%) had almost twice as many errors as handwritten scripts (p < 0.001) mainly due to systemic inbuilt errors. CONCLUSION: The application of increasing degrees of technological complexity does not automatically reduce error rate. This is especially apparent when technology is not integrated into human factors engineering and persistent critical assessment.

Striking a balance between usability and quality control in electronic health records.

BACKGROUND: This project is the first formal usability review of the hybrid electronic medical registry (HEMR) since its implementation in 2012. METHODS: A synchronous usability evaluation by novice operators was followed by a survey of veteran users. The usability evaluation was done by moderated think-aloud interview while completing tasks for a mock patient. The veteran survey was paper-based and focused on satisfaction of the system. RESULTS: A total of 141 comments on system errors were identified by the novice doctors. These consisted of 123 unique problems, of which three were hardware faults and were thus excluded. The identified issues were categorised into errors of control (27%), minimalist (21%), error (17%), match (13%), flexibility, visibility and consistency (9% each), and history (4%). Every unique usability violation was evaluated by the three experts who agreed that 82 of the 141 errors (58%) were valid and applicable. The other 59 items were rejected, not only because of the inability to reproduce some errors or programme shortcomings, but also because a series of "hurdles" were purposely included in the software to decrease cognitive dissonance and reduce error by the users. The survey of veteran users showed high levels of contentment with the system with regards to efficiency, satisfaction and preference. CONCLUSION: Despite many usability complaints by novices, almost half of them were rejected. Although usability in electronic health systems is important, it can often be sacrificed for more imperative aims such as safety, error filtering and clinical decision support.

Significance of HbA1c levels in diabetic retinopathy extremes in South Africa.

BACKGROUND: Diabetic retinopathy (DR) is one of the leading causes of blindness in sub-Saharan Africa and globally, placing a huge disease burden on patients and the public health system. DR varies in severity from non-proliferative to proliferative DR (PDR). OBJECTIVES: Using a monitor of medium- to long-term blood glucose control, to determine the association between glycated haemoglobin (HbA1c) levels in patients with PDR and those with no DR. METHODS: A prospective, cross-sectional study was conducted at McCord Provincial Eye Hospital in Durban, South Africa. We studied only patients diagnosed with diabetes mellitus (DM) for >1 year who had either PDR or no DR, and compared their HbA1c levels. Patients with non-proliferative DR were not included. RESULTS: Patients with PDR had significantly higher HbA1c levels than those with no DR. Patients with type 1 DM had higher HbA1c levels than patients with type 2 DM in both the PDR and no-DR groups. Older patients (>70 years) had lower HbA1c levels than younger patients. Gender, race and duration of diabetes had no influence on HbA1c levels. CONCLUSIONS: PDR was associated with higher HbA1c in type 2 DM in all races and age groups and was independent of duration of disease. The trend was the same for type 1 DM, but significance could not be reached, probably because of small numbers in this subset of patients.

A protocol for the Development of Core Outcome Sets for Endodontic Treatment modalities (COSET): an international consensus process.

BACKGROUND: The outcome of endodontic treatment is generally assessed using a range of patient and clinician-centred, non-standardised clinical and radiographic outcome measures. This makes it difficult to synthesise evidence for systematic analysis of the literature and the development of clinical guidelines. Core outcome sets (COS) represent a standardised list of outcomes that should be measured and reported in all clinical studies in a particular field. Recently, clinical researchers and guideline developers have focussed on the need for the integration of a patient-reported COS with clinician-centred measures. This study aims to develop a COS that includes both patient-reported outcomes and clinician-centred measures for various endodontic treatment modalities to be used in clinical research and practice. METHODS: To identify reported outcomes (including when and how they are measured), systematic reviews and their included clinical studies, which focus on the outcome of endodontic treatment and were published between 1990 and 2020 will be screened. The COSs will be defined by a consensus process involving key stakeholders using semi-structured interviews and an online Delphi methodology followed by an interactive virtual consensus meeting. A heterogeneous group of key 'stakeholders' including patients, general dental practitioners, endodontists, endodontic teachers, clinical researchers, students and policy-makers will be invited to participate. Patients will establish, via interactive interviews, which outcomes they value and feel should be included in a COS. In the Delphi process, other stakeholders will be asked to prioritise outcomes identified from the literature and patient interviews and will have the opportunity at the end of the first round to add outcomes that are not included, but which they consider relevant. Feedback will be provided in the second round, when participants will be asked to prioritise the list again. If consensus is reached, the remaining outcomes will be discussed at an online meeting and agreement established via defined consensus rules of outcome inclusion. If consensus is not reached after the second round, a third round will be conducted with feedback, followed by the online meeting. Following the identification of a COS, we will proceed to identify how and when these outcomes are measured. DISCUSSION: Using a rigorous methodology, the proposed consensus process aims to develop a COS for endodontic treatment that will be relevant to stakeholders. The results of the study will be shared with participants and COS users. To increase COS uptake, it will also be actively shared with clinical guideline developers, research funders and the editors of general dental and endodontology journals. TRIAL REGISTRATION: COMET 1879. 21 May 2021.

Surgical data recording in the operating room: a systematic review of modalities and metrics.

INTRODUCTION: Operating room recording, via video, audio and sensor-based recordings, is increasingly common. Yet, surgical data science is a new field without clear guidelines. The purpose of this study is to examine existing published studies of surgical recording modalities to determine which are available for use in the operating room, as a first step towards developing unified standards for this field. METHODS: Medline, EMBASE, CENTRAL and PubMed databases were systematically searched for articles describing modalities of data collection in the operating room. Search terms included 'video-audio media', 'bio-sensing techniques', 'sound', 'movement', 'operating rooms' and others. Title, abstract and full-text screening were completed to identify relevant articles. Descriptive statistical analysis was performed for included studies. RESULTS: From 3756 citations, 91 studies met inclusion criteria. These studies described 10 unique data-collection modalities for 17 different purposes in the operating room. Data modalities included video, audio, kinematic and eye-tracking among others. Data-collection purposes described included surgical trainee assessment, surgical error, surgical team communication and operating room efficiency. CONCLUSION: Effective data collection and utilization in the operating room are imperative for the provision of superior surgical care. The future operating room landscape undoubtedly includes multiple modalities of data collection for a plethora of purposes. This review acts as a foundation for employing operating room data in a way that leads to meaningful benefit for patient care.

Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) guidelines: a development protocol.

Diagnostic accuracy studies play an important role in informing clinical practice and patient management, by evaluating the ability of diagnostic testing and imaging to identify the presence or absence of a disease or condition. These studies compare the relative diagnostic strength of the test or device with a reference standard, therefore, guiding clinical decisions on the reliability of the test, the need for further tests, and whether to monitor or treat a particular condition. Inadequate and incomplete reporting of diagnostic accuracy studies can disguise methodological deficiencies and ultimately result in study bias and the inability to translate research findings into daily clinical practice. The Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) guidelines are being developed in order to improve the accuracy, transparency, completeness and reproducibility of diagnostic accuracy studies in the speciality of Endodontology. The aim of this paper is to report the process used to develop the PRIDASE guidelines based on a well-established consensus process. The project leaders (PD, VN) formed a steering committee of nine members (PD, VN, PA, AF, DR, SP, CK, MP, HD) to oversee and manage the project. The PRIDASE steering committee will develop the initial draft of the PRIDASE guidelines by adapting and modifying the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 guidelines, adding new items related specifically to the nature of Endodontics and incorporate the Clinical and Laboratory Images in Publication (CLIP) principles. The initial guidelines will consist of a series of domains and individual items and will be validated by the members of a PRIDASE Delphi Group (PDG) consisting of a minimum of 30 individuals who will evaluate independently the individual items based on two parameters: 'clarity' using a dichotomous scoring (yes/no) and 'suitability' for inclusion using a 9-point Likert Scale. The scores awarded by each member and any suggestions for improvement will be shared with the PDG to inform an iterative process that will result in a series of items that are clear and suitable for inclusion in the new PRIDASE guidelines. Once the PDG has completed its work, the steering committee will create a PRIDASE Meeting Group (PMG) of 20 individuals from around the world. Members of the PDG will be eligible to be the part of PMG. The draft guidelines and flowchart approved by the PDG will then be presented for further validation and agreement by the PMG. As a result of these discussions, the PRIDASE guidelines will be finalized and then disseminated to relevant stakeholders through publications and via the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website (http://pride-endodonticguidelines.org). Periodic updates to the PRIDASE guidelines will be made based on feedback from stakeholders and end-users.

The management of ocular and peri-ocular trauma needs to be co-ordinated according to ATLS principles and requires multi-disciplinary collaboration.

INTRODUCTION: This project set out to focus on ocular (globe) and peri-ocular trauma and to describe the spectrum of injuries seen in a busy South African trauma unit and to document their management and outcome. RESULTS: During the period November 2012 to April 2020, a total of 12 115 patients were managed by the Pietermaritzburg Metropolitan Trauma Service (PMTS) at Greys Hospital in Pietermaritzburg, South Africa. Of these 2194 (11%) sustained ocular or peri-ocular injury. Of these 2194 patients, 1069 (83%) were male. 83% of injuries (n=1076) were classified as primarily blunt injury and 17% as a primarily sharp/penetrating mechanism. A substantial number of patients required a life-saving emergency intervention. These included resuscitation in 242 cases (19%) and active airway intervention was in 290 (22%). In total 919 (71%) patients required urgent surgery to the peri-ocular region. Slightly over half (55%) of these the surgery was performed by a single discipline. The rest needed procedures by two or more disciplines. The disciplines involved included ophthalmology, maxillofacial, plastic, ENT and neurosurgery. Plastic surgery was involved in 683 cases (53%). A total of 341 distant surgeries were required - These included orthopaedic operations, laparotomy and vascular operations. Of the 1294 cases in this study, 42 (3%) died before discharge and 99 (8%) were discharged with a GCS lower than 10. The primary skill set for management of these injuries is identified. CONCLUSION: Although the management of immediate life and organ threatening injuries takes priority, ocular and peri-ocular trauma may damage a number of important structures and their comprehensive management requires a multi-disciplinary team of specialists or, in austere environments, a font-line medical team with a diverse skill set.

Obesity and Morbidity Risk in the U.S. Veteran.

The obesity epidemic in the United States has been well documented and serves as the basis for a number of health interventions across the nation. However, those who have served in the U.S. military (Veteran population) suffer from obesity in higher numbers and have an overall disproportionate poorer health status when compared to the health of the older non-Veteran population in the U.S. which may further compound their overall health risk. This study examined both the commonalities and the differences in obesity rates and the associated co-morbidities among the U.S. Veteran population, utilizing data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS). These data are considered by the Centers for Disease Control and Prevention (CDC) to be the nation's best source for health-related survey data, and the 2018 version includes 437,467 observations. Study findings show not only a significantly higher risk of obesity in the U.S. Veteran population, but also a significantly higher level (higher odds ratio) of the associated co-morbidities when compared to non-Veterans, including coronary heart disease (CHD) or angina (odds ratio (OR) = 2.63); stroke (OR = 1.86); skin cancer (OR = 2.18); other cancers (OR = 1.73); chronic obstructive pulmonary disease (COPD) (OR = 1.52), emphysema, or chronic bronchitis; arthritis (OR = 1.52), rheumatoid arthritis, gout, lupus, or fibromyalgia; depressive disorders (OR = 0.84), and diabetes (OR = 1.61) at the 0.95 confidence interval level.

Impact of motion artefacts and motion-artefact correction on diagnostic accuracy of apical periodontitis in CBCT images: an ex vivo study in human cadavers.

AIM: To assess the impact of motion artefacts and motion-artefact correction on diagnostic accuracy of apical periodontitis (AP) in CBCT images. METHODOLOGY: Based on clinical and radiographic inspection of 40 formalin-fixated human jaw specimens, 77 roots in 45 teeth (molars and premolars), with various disease and treatment state, were selected. The specimens were mounted on a robot simulating 3-mm movement types (nodding, lateral rotation and tremor). CBCT images with and without (controls) movements were acquired in four CBCT units: without motion-artefact correction in Cranex 3Dx, Orthophos SL 3D, and Promax 3D Mid, and with motion-artefact correction in Promax 3D Mid and X1. Three observers blindly assessed (i) whether the images were interpretable and (ii) if AP was present (5-step probability index). Histopathology provided the reference standard for presence of AP. Weighted Kappa statistics described inter-observer agreement. Estimates of diagnostic accuracy were assessed by means of receiver operator characteristic (ROC) curve analysis. Area under the curve (AUC) provided a measure of accuracy, and paired-sample AUC difference tests compared differences amongst the CBCT units and movement types. RESULTS: Observer agreement was substantial for control images, moderate for motion-artefact corrected images and fair for images without motion-artefact correction. When movement was present, motion-artefact correction reduced the percentage of images scored as noninterpretable or with uncertain disease state (score 3 in the 5-step probability index). Control images were not perfectly accurate (both false-positive and false-negative results were present; AUC 0.750-0.799). Images acquired with movement and without motion-artefact correction (AUC 0.541-0.709) were associated with significantly lower accuracy than control images (P < 0.05). With motion-artefact correction, accuracy was comparable to that observed in control images (AUC 0.732-0.790). CONCLUSIONS: Diagnostic accuracy of apical periodontitis in CBCT images was dependent on the presence of motion artefacts (i.e. lower accuracy associated with the presence of movement). Motion-artefact correction systems positively influenced image interpretability and diagnostic accuracy.

Diagnostic accuracy of cone beam computed tomography used for assessment of apical periodontitis: an ex vivo histopathological study on human cadavers.

AIM: To assess the diagnostic accuracy of Cone Beam Computed Tomography (CBCT) to diagnose apical periodontitis (AP) using histopathology of ex vivo human jaws as the reference standard. METHODOLOGY: Based on periapical radiographs of jaw specimens from human bodies donated for science, a sample of 223 teeth with 340 roots including all tooth groups, and different disease and treatment statuses was selected. Cone Beam Computed Tomography was performed using Cranex® 3Dx (Soredex Oy, Tuusula, Finland), small field-of-view (5 × 5 cm), and isotropic resolution 0.085 mm. Three observers assessed the presence of AP using a probability index. Histopathological examination of the periapical area was used as a reference standard to calculate estimates of diagnostic accuracy. RESULTS: For non-root filled teeth all estimates of diagnostic accuracy; sensitivity (SENS), specificity (SPEC), positive predictive value (PPV) and negative predictive value (NPV) were high. All estimates were lower for root filled teeth. When mild AP was classified as 'AP', SENS, SPEC and NPV were significantly lower in root filled roots (P < 0.001 in all cases). The same tendency was seen when mild AP was classified as 'No AP' but here only the difference in SPEC was significant (P < 0.001). CONCLUSION: The diagnostic accuracy of CBCT used for diagnosis of AP is dependent on the treatment status of the tooth. For non-root filled teeth the diagnostic accuracy of CBCT is high and almost all cases of AP can be diagnosed correctly with only a very small risk of over-diagnosis. All diagnostic accuracy parameters were lower for root filled roots, hence the diagnosis of AP on root filled roots using CBCT was less accurate.

Predicting mortality and incident immobility in older Belgian men by characteristics related to sarcopenia and frailty.

There is an increasing awareness of sarcopenia in older people. We applied machine learning principles to predict mortality and incident immobility in older Belgian men through sarcopenia and frailty characteristics. Mortality could be predicted with good accuracy. Serum 25-hydroxyvitamin D and bone mineral density scores were the most important predictors. INTRODUCTION: Machine learning principles were used to predict 5-year mortality and 3-year incident severe immobility in a population of older men by frailty and sarcopenia characteristics. METHODS: Using prospective data from 1997 on 264 older Belgian men (n = 152 predictors), 29 statistical models were developed and tuned on 75% of data points then validated on the remaining 25%. The model with the highest test area under the curve (AUC) was chosen as the best. From these, ranked predictor importance was extracted. RESULTS: Five-year mortality could be predicted with good accuracy (test AUC of .85 [.73; .97], sensitivity 78%, specificity 89% at a probability cut-off of 22.3%) using a Bayesian generalized linear model. Three-year incident severe immobility could be predicted with fair accuracy (test AUC .74 [.57; .91], sensitivity 67%, specificity 78% at a probability cut-off of 14.2%) using a multivariate adaptive regression splines model. Serum 25-hydroxyvitamin D levels and hip bone mineral density scores were the most important predictors of mortality, while biochemical androgen markers and Short-Form 36 Physical Domain questions were the most important predictors of immobility. Sarcopenia assessed by lean mass estimates was relevant to mortality prediction but not immobility prediction. CONCLUSIONS: Using advanced statistical models and a machine learning approach 5-year mortality can be predicted with good accuracy using a Bayesian generalized linear model and 3-year incident severe immobility with fair accuracy using a multivariate adaptive regression splines model.

Impact of cone beam computed tomography on periapical assessment and treatment planning five to eleven years after surgical endodontic retreatment.

AIM: To evaluate how additional information from Cone Beam CT (CBCT) impacts on periapical assessment and treatment planning based on clinical examination and periapical radiographs (PR) in cases followed up five to eleven years after surgical endodontic retreatment (SER). METHODOLOGY: Patients receiving SER during 2004-2010 were reinvited for follow-up examination including clinical examination, PR, and CBCT. In total, 108 patients (119 teeth) were reinvited, 74 patients (83 teeth) accepted to participate. Three observers initially assessed PR according to the four-scaled, increasing disease severity criteria by Rud et al. (International Journal of Oral Surgery, 1, 1972 and 195) and Molven et al. (International Journal of Oral and Maxillofacial Surgery, 16, and 432): 'Radiographic assessment A'. By including clinical information 'Treatment plan A' was made as follows: 1) no treatment, 2) further observation, 3) SER reoperation (SER-R), or 4) extraction. Hereafter, the CBCT volume was assessed and the information incorporated for 'Radiographic assessment B' followed by 'Treatment plan B'. Agreement between radiographic assessments and between treatment plans was recorded and assessed statistically by Stuart-Maxwell test for marginal homogeneity. RESULTS: Nine teeth had been extracted; thus, the final analysis included 74 teeth (66 patients). The radiographic assessment was changed as a result of the CBCT evaluation in 38 cases (51.4%), of which 35 (47.3%) were to a higher Rud & Molven score, P < 0.001. The treatment plan was changed for 18 teeth (24.3%). For 14 teeth (18.9%), the change was from no treatment or further observation to a more invasive treatment plan (SER-R or extraction), P = 0.005. CONCLUSION: The use of CBCT for long-term follow-up after SER led to more cases diagnosed with persisting or recurrent apical periodontitis and hence often to the recommendation of a more invasive treatment modality.

Clinical fracture risk evaluated by hierarchical agglomerative clustering.

Clustering analysis can identify subgroups of patients based on similarities of traits. From data on 10,775 subjects, we document nine patient clusters of different fracture risks. Differences emerged after age 60 and treatment compliance differed by hip and lumbar spine bone mineral density profiles. INTRODUCTION: The purposes of this study were to establish and quantify patient clusters of high, average and low fracture risk using an unsupervised machine learning algorithm. METHODS: Regional and national Danish patient data on dual-energy X-ray absorptiometry (DXA) scans, medication reimbursement, primary healthcare sector use and comorbidity of female subjects were combined. Standardized variable means, Euclidean distances and Ward's D2 method of hierarchical agglomerative clustering (HAC), were used to form the clustering object. K number of clusters was selected with the lowest cluster containing less than 250 subjects. Clusters were identified as high, average or low fracture risk based on bone mineral density (BMD) characteristics. Cluster-based descriptive statistics and relative Z-scores for variable means were computed. RESULTS: Ten thousand seven hundred seventy-five women were included in this study. Nine (k = 9) clusters were identified. Four clusters (n = 2886) were identified based on low to very low BMD with differences in comorbidity, anthropometrics and future bisphosphonate compliance. Two clusters of younger subjects (n = 1058, mean ages 30 and 51 years) were identified as low fracture risk with high to very high BMD. A mean age of 60 years was the earliest that allowed for separation of high-risk clusters. DXA scan results could identify high-risk subjects with different antiresorptive treatment compliance levels based on similarities and differences in lumbar spine and hip region BMD. CONCLUSIONS: Unsupervised HAC presents a novel technology to improve patient characteristics in bone disease beyond traditional T-score-based diagnosis. Technological and validation limitations need to be overcome to improve its use in internal medicine. Current DXA scan indication guidelines could be further improved by clustering algorithms.

The selective 5-HT6 receptor antagonist SLV has putative cognitive- and social interaction enhancing properties in rodent models of cognitive impairment.

In the present study, our aim was to investigate whether the novel highly selective 5-hydroxytryptamine6 (5-HT6) receptor antagonist SLV can ameliorate impairments in cognition and social interaction with potential relevance for both schizophrenia and Alzheimer's disease (AD). SLV sub-chronically - treated Wistar rats reared in isolation showed significantly enhanced prepulse inhibition (PPI) and object recognition performance when compared to vehicle - treated rats. In the isolated rats, also a significant reduction in expression of hippocampal neural cell adhesion molecule polysialylation (NCAM-PSA) was found which was ameliorated following treatment with SLV (30mg/kg). The social engagement deficit in rats exposed in utero (on gestational day 12.5) to valproic acid (VPA) was reversed by treatment with SLV (30mg/kg). SLV (20 and 30mg/kg, p.o.) fully reversed MK-801 - induced deficits in the ORT and also scopolamine - induced deficits in both the Object Recognition Task (ORT) and Object Location Task (OLT) in Wistar rats. In addition, a combination of sub-optimal doses of SLV and donepezil attenuated scopolamine-induced ORT deficits. Furthermore, SLV (10mg/kg, p.o.) reversed spontaneous alternation deficits in the T-maze induced by MK-801 administration in Swiss mice and in aged C57Bl/6J mice. SLV additionally improved T-Maze spatial learning and passive avoidance learning in Sprague-Dawley rats with amyoid-beta (Aß) injections into the hippocampus. In contrast, no benefits were found with SLV or the tested reference compounds (donepezil and RVT-101) on cognitive performance of 12months old Tg2576 mice. Also, in the social recognition task, an absence of cognitive enhancing properties was observed with SLV on "normal forgetting" in Wistar rats. Finally, analysis of spontaneous inhibitory postsynaptic currents (sIPSCs) frequency recorded from pyramidal cells revealed a reduction in the presence of 1µM of SLV. In conclusion, SLV was investigated in several rodent animal models and found to be effective at a least effective dose (LED) of 20mg/kg and 10mg/kg (p.o.) in the rat and the mouse, respectively.

Comparison of magneto-optical properties of various excitonic complexes in CdTe and CdSe self-assembled quantum dots.

We present a comparative study of two self-assembled quantum dot (QD) systems based on II-VI compounds: CdTe/ZnTe and CdSe/ZnSe. Using magneto-optical techniques we investigated a large population of individual QDs. The systematic photoluminescence studies of emission lines related to the recombination of neutral exciton X, biexciton XX, and singly charged excitons (X(+), X(-)) allowed us to determine average parameters describing CdTe QDs (CdSe QDs): X-XX transition energy difference 12 meV (24 meV); fine-structure splitting δ1=0.14 meV (δ1=0.47 meV); g-factor g = 2.12 (g = 1.71); diamagnetic shift γ=2.5 µeV T(-2) (γ =1.3 µeV T(-2)). We find also statistically significant correlations between various parameters describing internal structure of excitonic complexes.

Optimal age of commencing and discontinuing thiazide therapy to protect against fractures.

UNLABELLED: A study of national Danish patient data with regard to thiazide diuretics vs. non-treatment. We find that after age 83 years, thiazides increase the 10-year risk of major fractures. We also find that thiazides can be stopped after 63 years old to possibly protect against fracture occurrence. INTRODUCTION: The purpose of this study was to retrospectively examine the optimal age for commencing and discontinuing thiazide therapy to protect from osteoporotic fractures. METHODS: A population-based, retrospective matched cohort study was done using national data of 2.93 million Danish subjects. Ten-year crude and adjusted age-grouped hazard ratios (HRs) of fracture occurrence were stratified by age of commencing thiazides compared to non-exposure. Separate analyses were done on Anatomical Therapeutic Chemical Classification System (ATC) codes C03AA and C03AA + C03AB compiled. Ten-year crude HRs of fracture occurrence for discontinuing vs. continuing thiazides were estimated and stratified by age for the two groups. RESULTS: For C03AB alone (97.1 % of thiazide prescriptions), adjusted 10-year HRs of fracture occurrence were significantly increased for thiazide commencement after age 83 years and comparable to non-exposure for commencement between ages 50 and 83 years. For C03AA + C03AB, 10-year adjusted HRs of fracture occurrence were significantly increased from ages 73 years and upwards. Crude 10-year HRs of fracture occurrence were significantly decreased for discontinuing vs. continuing thiazides at or after age 63 years for C03AB and age 77 years for C03AA + C03AB. CONCLUSIONS: No significantly protective effect of thiazides was found on fracture occurrence compared to non-users, but evidence that thiazides increase the 10-year adjusted HR risk of fractures if prescribed after the age of 83 years for C03AB and 73 years for C03AA + C03AB. Discontinuing thiazides at or after age 63 years for C03AB or 77 years for C03AA & C03AB significantly decreases the 10-year risk of fractures compared to continuing thiazides. Further prospective studies are warranted.

Continuous and long-term treatment is more important than dosage for the protective effect of thiazide use on bone metabolism and fracture risk.

BACKGROUND: Data from observational studies have suggested that thiazide diuretics protect against fractures. Few studies have investigated time frames from initiation of treatment to fracture occurrence. OBJECTIVE: To evaluate the time to spinal, hip, femur, wrist and upper extremity fracture occurrence before and after thiazide exposure. METHODS: A matched retrospective cohort study of patient information from national Danish patient databases was conducted. Patients with reimbursed prescriptions for noncompounded thiazide diuretics with potassium supplementation (Anatomical Therapeutic Chemical classification system code C03AB) between 1996 and 2011 were matched with nonexposed control subjects by date of birth and gender. Weekly odds ratios (ORs) of fracture occurrence and total incidence rates (IRs) and incidence rate ratios (IRRs) of fracture risk were calculated for the periods before treatment initiation, weeks 1-42 and weeks 43-780. RESULTS: A total of 1,602,141 'thiazide exposure periods' (46,8271 individuals) and 1,530,233 'nonexposure periods' (655,399 individuals) were included in the analysis. Thiazide use was associated with factors of increased de novo fracture risk. Weekly adjusted fracture risk between exposure and nonexposure was increased prior to commencing thiazide therapy, further increasing from weeks 1-42 weeks and then decreasing gradually from weeks 43-780. There was a decreasing trend in total age-adjusted risk during these periods: IRR [95% confidence interval 1.44 [1.42; 1.47], 1.27 [1.24; 1.29] and 1.14 [1.11; 1.18], respectively. Prescription patterns showed several treatment breaks amongst thiazide users. CONCLUSIONS: It appears that thiazides reduce the background risk of fracture that is increased prior to commencing therapy. Long duration and continuity of thiazide exposure seems to be important to obtain this protective effect on fracture risk, but we have found in this study that this approach is not always used in clinical practice.

Secondary pool boiling effects.

A pool boiling phenomenon referred to as secondary boiling effects is discussed. Based on the experimental trends, a mechanism is proposed that identifies the parameters that lead to this phenomenon. Secondary boiling effects refer to a distinct decrease in the wall superheat temperature near the critical heat flux due to a significant increase in the heat transfer coefficient. Recent pool boiling heat transfer experiments using femtosecond laser processed Inconel, stainless steel, and copper multiscale surfaces consistently displayed secondary boiling effects, which were found to be a result of both temperature drop along the microstructures and nucleation characteristic length scales. The temperature drop is a function of microstructure height and thermal conductivity. An increased microstructure height and a decreased thermal conductivity result in a significant temperature drop along the microstructures. This temperature drop becomes more pronounced at higher heat fluxes and along with the right nucleation characteristic length scales results in a change of the boiling dynamics. Nucleation spreads from the bottom of the microstructure valleys to the top of the microstructures, resulting in a decreased surface superheat with an increasing heat flux. This decrease in the wall superheat at higher heat fluxes is reflected by a "hook back" of the traditional boiling curve and is thus referred to as secondary boiling effects. In addition, a boiling hysteresis during increasing and decreasing heat flux develops due to the secondary boiling effects. This hysteresis further validates the existence of secondary boiling effects.

Characterisation of Elastic and Acoustic Properties of an Agar-Based Tissue Mimicking Material.

As a first step towards an acoustic localisation device for coronary stenosis to provide a non-invasive means of diagnosing arterial disease, measurements are reported for an agar-based tissue mimicking material (TMM) of the shear wave propagation velocity, attenuation and viscoelastic constants, together with one dimensional quasi-static elastic moduli and Poisson's ratio. Phase velocity and attenuation coefficients, determined by generating and detecting shear waves piezo-electrically in the range 300 Hz-2 kHz, were 3.2-7.5 ms(-1) and 320 dBm(-1). Quasi-static Young's modulus, shear modulus and Poisson's ratio, obtained by compressive or shear loading of cylindrical specimens were 150-160 kPa; 54-56 kPa and 0.37-0.44. The dynamic Young's and shear moduli, derived from fitting viscoelastic internal variables by an iterative statistical inverse solver to freely oscillating specimens were 230 and 33 kPa and the corresponding relaxation times, 0.046 and 0.036 s. The results were self-consistent, repeatable and provide baseline data required for the computational modelling of wave propagation in a phantom.