Internal circadian misallignment in a mouse model of chemotherapy induced fatigue

BACKGROUND

Cancer survivors can experience long lasting fatigue resulting in a lower quality of life. How chemotherapy treatment contributes to this fatigue is poorly understood. Previously we have shown in a mouse model of cancer related fatigue that doxorubicin treatment induces fatigue-like symptoms related to disturbed circadian rhythms. However, the specific components of the circadian regulatory circuitry affected by doxorubicin treatment remained unclear. Therefore we investigated the role of the central circadian clock, the suprachiasmatic nucleus (SCN), in chemotherapy-induced fatigue.

METHODS

We measured circadian controlled behavior and multiunit neuronal activity in the SCN in freely moving mice exhibiting fatigue-like behavior after doxorubicin treatment under both light-dark (LD) and constant dark (DD) conditions. Additionally, we assessed the expression of inflammation related genes in spleen and kidney as potential inducers of CRF.

RESULTS

Doxorubicin treatment significantly reduced both the running wheel activity and time spent using the running wheel for over five weeks after treatment. In contrast to the pronounced effects on behavior and neuronal activity of doxorubicin on circadian rhythms, peripheral inflammation markers only showed minor differences, five weeks after the last treatment. Surprisingly, the circadian SCN neuronal activity under both LD and DD conditions was not affected. However, the circadian timing of neuronal activity in peri-SCN areas (the brain areas surrounding SCN) and circadian rest-activity behavior was strongly affected by doxorubicin, suggesting that the output of the SCN was altered. The reduced correlation between the SCN neuronal activity and behavioral activity after doxorubicin treatment, suggests that the information flow from the SCN to the periphery was disturbed.

CONCLUSION

Our preclinical study suggests that chemotherapy-induced fatigue disrupts the circadian rhythms in peripheral brain areas and behavior downstream from the SCN, potentially leading to fatigue like symptoms. Our data suggest that peripheral inflammation responses are less important for the maintenance of fatigue. Chronotherapy that realigns circadian rhythms could represent a non-invasive way to improve patient outcomes following chemotherapy.

Foreign object detection considering misalignment effect for wireless EV charging system

Foreign object detection (FOD) is crucial to preventing wireless electric vehicle charging (WEVC) systems from thermal risk caused by intruded metals in the charging area. In practice, the spatial misalignment between EV and ground-assembled power transmitter is evitable. Unfortunately, according to our quantitative analysis based on conventional voltage-difference-based method, a misalignment of merely tens of mm has been enough to severely deteriorate the FOD accuracy. To combat this misalignment effect, a FOD strategy based on passive sensing coils utilizing voltage vector decomposition (VVD) is proposed in this paper. The proposed strategy can be invariant to misalignment in an automatic manner, during the whole charging process, and regardless of the resonance state of charging circuit. To facilitate VVD implementation, a method called inductance-misalignment mapping (IMM) is devised to obtain the spatial misalignment of EV in real time, and it can be executed by reusing the sensing coils without introducing extra cost. The effectiveness of optimized sensing coils with the proposed FOD method is validated successfully using a commercialized 3-kW prototype working from light load to rated load.

Incidence and Risk Factors of Repositioning Surgery to Correct Misalignment of Toric Intraocular Lenses after Cataract Surgery: A Single-Center Retrospective Observational Study

PURPOSE

The aim of this study was to analyze the incidence and outcomes of repositioning surgery to correct misalignment of several toric intraocular lenses (IOLs) after cataract surgery.

METHODS

In this retrospective study, patients who underwent repositioning surgery to correct misalignment of toric IOLs following cataract surgery between January 2019 and December 2021 were enrolled. The medical data on patients' age, gender, preoperative axial length, corneal astigmatism, the axis of astigmatism, IOL models, IOL axis, uncorrected distance visual acuity, residual refraction, and postoperative outcomes were analyzed.

RESULTS

Among the 1,135 eyes implanted with toric IOLs at Qingdao Eye Hospital, 23 (2.026%, 23/1,135) underwent repositioning surgery. Univariate analysis revealed that the incidence of repositioning surgery was significantly lower with AcrySof (0.636%, 5/786) than with ZEISS (2.959%, 5/169) and TECNIS (7.222%, 13/180) IOL platforms; the incidence of repositioning surgery with monofocal toric IOLs (1.169%, 11/941) was significantly lower than multifocal toric IOLs (6.186%, 12/194) (p < 0.001); additionally, a significant difference in age was also observed (p = 0.002). Multivariate logistic regression analysis showed that the IOL platform (p = 0.004) and younger age (p = 0.006) were independent risk factors for repositioning surgery.

CONCLUSION

The incidence of repositioning surgery of toric IOLs after cataract surgery was 2.026%. It was linked to the IOL platform, multifocal toric IOLs, and younger age.

Orientation of the Cochlea From a Surgeon's Perspective

Background

One of the mechanisms that cause tip fold-over is a misalignment between the electrode array's coiling direction and the cochlea's curving direction.

Objectives

We reviewed surgical videos and computed tomography (CT) datasets of the patients who underwent cochlear implantation procedures from January 2010 to December 2021, paying particular attention to the cochlea's orientation in the surgeon's microscopic view.

Methods

CT dataset and video recordings were analyzed to measure the "slope angle," which is the angle between the cochlea's coiling plane and the horizontal plane.

Results

There were 220 cases that met the criteria and completed the analysis. The mean slope angle was 12.1° ± 9.5°, with a minimum of -9.4° and maximum of 44.6°. However, each surgeon had a favored slope angle range.

Conclusion

Understanding the slope angle and making an effort to reduce the chance of misalignment during electrode insertion may help prevent tip fold-over of slim perimodiolar electrode arrays.

Controlling the angle between the distal locking screw and tibiotalar joint tangent helps to reduce the occurrence of misalignment of distal tibial fractures treated with intramedullary nail fixation

BACKGROUND

Studies have shown that on the coronal plane, whether the direction of the distal locking screw is parallel to the tangent line of the tibiotalar joint can be used to determine whether there is varus or valgus deformity after the treatment of distal tibial fractures with intramedullary nail (IMN) fixation. However, there has been no statistical analysis of the included angle on the coronal plane, and there have been no reports on whether there is a relationship between the direction of the distal locking screw on the sagittal plane or the included angle of the tangent line of the tibiotalar joint and the postoperative alignment of distal tibial fractures treated with IMN fixation.

OBJECTIVE

Our aim was to evaluate the relationship between the angles formed by the distal locking screw and the tibiotalar joint tangent (ADTTs) on the sagittal and coronal planes and postoperative alignment in the treatment of distal tibial fractures with IMN fixation.

METHODS

We performed a retrospective analysis of 100 patients with distal tibial fractures treated with IMN fixation using the suprapatellar approach. On the coronal and sagittal planes, the ADTTs were arranged from small to large and divided into 4 groups, namely, groups A, B, C and D. One-way ANOVA was used to compare the lateral distal tibial angle (LDTA) and anterior distal tibial angle (ADTA) among all groups, and the chi-square test was used to compare the incidence of postoperative tibial misalignment among all groups. Univariate analysis was performed using chi-square tests to identify factors that might be associated with dislocation, including fibular open reduction and internal fixation (ORIF), limited open reduction, ADTT, IMN diameter, injury mechanism, open vs. closed fracture, comminution, and fibular fracture level. Then, the statistically significant variables in the univariate analysis were included in a multivariate logistic regression equation to evaluate the independent factors related to misalignment.

RESULTS

On the coronal plane, the ADTTs of groups A, B, C and D were < 0°, 0°-1.3°, 1.3°-2.7° and > 2.7°, respectively. The mean LDTAs of groups B and C (0°-1.3° and 1.3°-2.7°), group A (< 0°) and group D (> 2.7°) were 89.5 ± 1.6°, 92.0 ± 3.2° and 85.8 ± 3.5°, respectively (P < 0.01). Deformity greater than 5° were more likely in groups A and D than groups B and C [14 of 50 (28%) vs. 1 of 50 (2%), P < 0.001]. On the sagittal plane, the ADTTs of groups A, B, C and D were < 8.9°, 8.9°-10.4°, 10.4°-11.7° and > 11.8°, respectively. The average ADTAs of groups B and C (8.9°-10.4° and 10.4°-11.7°), group A (< 8.9°) and group D (> 11.8°) were 80.4 ± 1.3°, 83.1 ± 3.7° and 77.9 ± 2.5°, respectively (P < 0.01). Deformity greater than 5° was more likely in groups A and D than groups B and C [13 of 50 (26%) vs. 0 of 50 (0%), P < 0.001]. An ADTT of 0°-2.7° on the coronal plane and 8.9°-11.7° on the sagittal plane (OR: 0.08, P = 0.02) and limited open reduction (OR: 0.21, P < 0.01) were independent factors that reduced the likelihood of misalignment.

CONCLUSION

The alignment of distal tibial fractures after surgery is sensitive to the ADTT and use of limited open reduction. Controlling the ADTT between 0° and 2.7° on the coronal plane and between 8.9° and 11.7° on the sagittal plane is helpful to reduce the occurrence of misalignment after the treatment of distal tibial fractures by IMN fixation.

Low-cost, microcontroller-based phase shift measurement system for a wireless power transfer prototype

Seeking to characterize and mitigate the adverse effects of misalignment in WPT applications, we present the design and construction of a low-cost wireless charger prototype and a novel phase-shift measurement system. The first is built using a half-bridge inverter and antennas with series-series compensation, while a microcontroller (Teensy 4.1) supplies high-frequency PWM signals. The measurement system comprises high-speed operational amplifiers and an exclusive OR gate. A resistor was used as load. On the other hand, the maximum power transfer efficiency occurs at the resonance frequency, nevertheless, this depends physically on the geometry of the coupling system. Using a 3D-printed displacement system, we created controlled vertical misalignments between the coils, thereby obtaining variations in the resonance frequency of the system and consequently, producing a proportional phase shift between the voltage and current waves of the transmitting antenna. As the experimental results demonstrate, the measurement system can process this high-frequency signal for the phase shift estimation and subsequently use it as a control variable in a proportional-integral controller, which adjusts the operation frequency of the system and brings it back to optimal conditions. This precise yet inexpensive implementation could find its application in EVs and biomedical devices' efficient wireless chargers.

Evaluation of the reduction, tightening and gripping performance of an innovative set screw technology for instrumented posterior lumbar fusion: A biomechanical study

BACKGROUND

Instrumented posterior lumbar fusion with top-loading pedicle screw systems (PSS) requires fully tightened set screws to achieve a secure fixation and symmetric load condition. This assumes a complete reduction of the rod by 90°, which is not always attainable in situ, especially under constraint. The objective of this work is to compare the mechanical performance of different innovative set screw technologies, which should improve the tightening process.

HYPOTHESIS

The hypotheses of the study are that modifications to the screw and screwdriver unit can (1) improve the quality of set screw tightening and (2) increase the axial gripping capacity of the construct.

MATERIALS AND METHODS

The four set screw technologies under investigation include a standard set screw with a flat surface (F-S; control group), a set screw with a convex surface (C-S) and a shaft tip method screwdriver used in combination with both flat (F-STM) and convex set screws (C-STM). The quality of set screw tightening is categorized as follows: failed=the rod is not completely reduced; reduced=the rod is successfully reduced but the set screw is not correctly fixed; good=remaining cases. An axial gripping capacity test is performed by a universal testing machine (Instron®) with a force capacity of 5kN.

RESULTS

Regarding the quality of set screw tightening, comparisons between F-S vs. F-STM, F-S vs. C-STM and between C-S vs. C-STM show statistically significant differences (p<0.001). The axial gripping capacity test shows mean gripping forces of 1223N (STD 331) in the F-STM group and of 1724N (STD 168) in the C-STM group with statistically significant differences between both groups (p=0.003).

DISCUSSION

Several biomechanical and clinical case studies have identified possible effects of misaligned rod-screw interfaces such as screw pull-out during rod reduction, screw loosening, screw or rod breakage, misalignment, adjacent segment degeneration and worsening of the clinical outcome. C-STM-technology thus supports controlled fixation in the sense of applying appropriate forces for correction or fixation during PSS assembly as well as friction-reduced final alignment and tightening with the aim to reduce implant loosening, hardware failure and reoperations, while respecting anatomical and biomechanical balance.

Objective evaluation of static and dynamic behavior of different toric silicone-hydrogel contact lenses

PURPOSE

The present study aimed to estimate how orientation position, recovery time, and contact lens decentration, associated with visual performance, may vary on several designs of the most recent toric silicone-hydrogel toric contact lenses in two-time different moments.

METHODS

To evaluate the toric silicone-hydrogel toric contact lens position and stability, it was conducted with a prospective, observational, randomized, and single-center case series including 95 astigmatic eyes wearing four toric silicone-hydrogel toric contact lenses for two weeks. Orientation and decentration were analyzed with ImageJ software from video-frames extracted with a Python application. Recovery time was evaluated after 45 degrees of inferior-temporal misorientation.

RESULTS

Evaluation of misorientation after 20 min of wear revealed the highest amount for Saphir RX, -20.41 ± 10.84 deg, and lowest for Air Optix Aqua for Astigmatism, -1.43 ± 7.48 deg. The highest horizontal misalignment was found for Air Optix Aqua for Astigmatism, -0.627 ± 0.330 mm, and lowest for Biofinity Toric, 0.004 ± 0.270 mm. Vertical misalignment presented the highest value for Acuvue Vita for Astigmatism, -0.652 ± 0.369 mm, and lowest for Air Optix Aqua for Astigmatism, -0.126 ± 0.231 mm. Recovery time showed the highest amount for Saphir RX, 80.70 ± 33.26 s, and lowest for Biofinity Toric 43.67 ± 23.70 s. Only Air Optix Aqua for Astigmatism presented significant differences after two-week of wear for misorientation (P = 0.02) and horizontal misalignment (P < 0.001). When pairwise comparisons are made between toric silicone-hydrogel toric contact lenses, significant differences (P < 0.001) are found.

CONCLUSIONS

Although there was acceptable fitting, based upon decentration, orientation, and recovery with the study contact lenses, the stabilization and profile design used in the Air Optix Aqua for Astigmatism helped to minimize rotation and vertical misalignment. In addition, the peri-ballast and thickness profile of the Biofinity Toric improved rotational recovery and horizontal misalignment compared to the other contact lenses. Finally, lenses with a better fitting profile showed better visual performance.

[Association between social jetlag and presenteeism in Japanese industry: A cross-sectional study]

OBJECTIVES

Research suggests that misalignment of the biological clock and social time, referred to as social jetlag (SJL),can induce physical and mental disorders. SJL may also be associated with presenteeism (i.e., a state in which workers are unable to perform sufficiently due to mental and physical health problems, even though they are going to work). However, the association between SJL and presenteeism among workers in Japan remains unclear. This study aimed to verify the following hypotheses in a sample of workers in an industrial setting in Japan: "Workers exhibiting SJL have a high degree of work functioning impairment due to presenteeism" and "An association between SJL and presenteeism exists, even when taking work style and sleep-related factor into consideration."

METHODS

A self-administered questionnaire survey was conducted with 1,573 workers in the manufacturing industry. Of these, 1,501 participants responded (response rate: 95.4%). Individuals who provided invalid answers or used alarm clocks to wake on work-free days were excluded, according to the Munich Chronotype Questionnaire (MCTQ) guidelines. The final sample comprised 980 participants (80.7% male; average age: 44.4 [SD 11.3] years). SJL was assessed using the MCTQ. Presenteeism was measured using the work functioning impairment scale. Using presenteeism as the dependent variable, we conducted hierarchical multiple regression analyses to compare the explanatory power of the different models. Independent variables were SJL, daily rest period between workdays, weekday sleep duration, and subjective insomnia. Models 2 and 3 were adjusted for age, sex, employment position, occupation, employment status, and working regulations.

RESULTS

Multiple regression analyses indicated that SJL was significantly and individually associated with presenteeism (β = .066, p = .038). After adjusting for work- and sleep-related variables (Models 2 and 3), SJL no longer contributed significantly to presenteeism. In the final model, daily rest periods (β = .076, p = .017) and subjective insomnia (β = .470, p < .001) remained significantly associated with presenteeism (adjusted R² = .239).

CONCLUSIONS

The hypothesis "Workers experiencing SJL have a high degree of work functioning impairment due to presenteeism" was supported in our univariate analysis. However, after considering the influence of subjective insomnia and daily rest periods, the association disappeared. Therefore, a direct relationship between SJL and presenteeism is not supported. Thus, the risk of presenteeism should be considered in two stages, first confirming the perception of insomnia among workers who experience SJL, and then considering the possibility of presenteeism occurring.

Influence of alignment and microstructure features on the mechanical properties and failure mechanisms of cellulose nanocrystals (CNC) films

The mechanical properties of cellulose nanocrystal (CNC) films critically depend on many microstructural parameters such as fiber length distribution (FLD), fiber orientation distribution (FOD), and the strength of the interactions between the fibers. In this paper, we use our coarse-grained molecular model of CNC to study the effect of length and orientation distribution and attractions between CNCs on the mechanical properties of neat CNCs. The effect of misalignment of a 2D staggered structure of CNC with respect to the loading direction was studied with simulations and analytical solutions and then verified with experiments. To understand the effect of FLD and FOD on the mechanical performance, various 3D microstructures representing different case studies such as highly aligned, randomly distributed, short length CNCs and long length CNCs were generated and simulated. According to the misalignment study, three different failure modes: sliding mode, mixed mode, and normal mode were defined. Also, comparing the effects of FOD, FLD, and CNC interaction strength, shows that the adhesion strength is the only parameter that can significantly improve the mechanical properties, regardless of loading direction or FOD of CNCs.

A dataset of micro-scale tomograms of unidirectional glass fiber/epoxy and carbon fiber/epoxy composites acquired via synchrotron computed tomography during in-situ tensile loading

We have performed synchrotron computed tomography on two different fiber-reinforced composites while they were being continuously in-situ loaded in 0° tension. One material is a glass/epoxy laminate and the other is a carbon/epoxy laminate. The voxel size is 1.1 µm, which allows clear recognition of the glass fibers, but not distinct individual carbon fibers. For each material, four loading steps are selected with approximately 0, 40, 73, and 95% of the failure load, and the 3D images of the four volumes from each material are overlaid. A volume of interest in the middle 0° ply is chosen and located in the 3D image of each loading step (Fig. 1). The cropped volumes of interest for each material are presented in this publication and are publicly available on Mendeley Data[1]. As examples of two frequently-used type of unidirectional fiber-reinforced composites, the presented data can be used for different microstructural analyses, including investigation of the 3D variability in fiber distribution and orientation, and their evolution during tensile loading. For example, we have performed fiber orientation analysis on this data, using our digital image correlation-based technique, in [2]. Moreover, real-time formation of fiber breaks with tensile loading can be investigated in the data.

Asking the Clock: How to Use Information from Questionnaires for Circadian Phenotyping

With the emergence of big data science, the question how we can easily collect meaningful information about circadian clock phenotypes in large human cohorts imposes itself. Here, we describe potentials and limitations of using questionnaires, specifically the Munich ChronoType Questionnaire (MCTQ), to characterize such circadian phenotypes. We also discuss scenarios when alternative methods might be more appropriate.

Spatiotemporal modeling of dengue fever risk in Puerto Rico

Dengue Fever (DF) is a mosquito vector transmitted flavivirus and a reemerging global public health threat. Although several studies have addressed the relation between climatic and environmental factors and the epidemiology of DF, or looked at purely spatial or time series analysis, this article presents a joint spatio-temporal epidemiological analysis. Our approach accounts for both temporal and spatial autocorrelation in DF incidence and the effect of temperatures and precipitation by using a hierarchical Bayesian approach. We fitted several space-time areal models to predict relative risk at the municipality level and for each month from 1990 to 2014. Model selection was performed according to several criteria: the preferred models detected significant effects for temperature at time lags of up to four months and for precipitation up to three months. A boundary detection analysis is incorporated in the modeling approach, and it was successful in detecting municipalities with historically anomalous risk.

Rotation of a toric intraocular lens with and without capsular tension ring: data from a multicenter non-inferiority randomized clinical trial (RCT)

BACKGROUND

Evaluation of clinical outcome in cohorts with versus without simultaneous implantation of a capsular tension ring (CTR) and a toric lens (Tecnis Toric). Main parameter was rotation referring - in contrast to misalignment - to the IOL axis change from immediately after implantation to the final postoperative position.

METHODS

Lens position was measured at baseline with the patient still in recumbent position, postoperative rotation was calculated by software. Postoperative evaluation included measurement three months after surgery or prior to an indicated revision surgery. Explorative re-evaluation of the underlying RCT's intent-to-treat population was performed for the entire sample and stratified for cohorts by 95% confidence intervals for binary endpoints' incidences (primary endpoint: absolute postoperative rotation ≤5 degrees; secondary endpoints: absolute deviation between achieved cylinder and target cylinder ≤0.5 dpt, postoperative corrected distance visual acuity (CDVA) ≥ 0.8). Data exploration was based on medians and quartiles.

SETTING

Outpatient study sites.

DESIGN

Re-evaluation based on data from a multicenter non-inferiority randomized clinical trial (RCT).

RESULTS

Sub cohorts (without CTR 89, with CTR 90 patients) did not present clinically relevant differences in preoperative characteristics: revision surgery was performed in 7 cases (3 without and 4 with CTR). Primary endpoint incidences for the total sample, without and with CTR were 90%/89%/90%; cylinder endpoint incidences were 46%/45%/46% and CDVA endpoint incidences 90%/92%/88%. Median absolute rotations were 1.74°/1.79°/1.72°, median absolute cylinder deviations 0.55/0.52/0.55 dpt and median visual acuity 1.0/1.0/1.0.

CONCLUSION

No clinically relevant differences between CTR subgroups were found; a satisfying three months rotational stability was achieved.

TRIAL REGISTRATION

The trial was registered retrospectively in the trial registry DRKS, trial registration number DRKS00015316 , date of registration 27. August 2018.

Self-extraction with and without a cervical collar: a biomechanical simulation study

OBJECTIVES

To compare self-extraction with and without a cervical collar in subjects at low risk of cervical spine injuries.

MATERIAL AND METHODS

Simulation study analyzing biomechanical data from inertial sensors to detect misalignment of the cervical spine during self-extraction with and without a cervical collar.

RESULTS

Misalignment was a mean (SD) 3.12 (34.62) degrees greater during self-extraction with a Stiffneck collar in place (95% CI, -15.33 to 21.57 degrees; P=.7234) than during extraction without a collar. Misalignment was also greater, by 5.95 (31.76) degrees, with an X-collar in place (95% CI, -10.98 to 22.87; P=.4654) than without a collar. The between-collar comparison of differences showed that misalignment was 2.83 (12.10) degrees greater with the X-collar (95% CI, -3.62 to 9.27 degrees; P=.3650).

CONCLUSION

Misalignment of the cervical spinal column is similar during self-extraction with or without a cervical collar in place.

Experimental Observation of the Effects of Translational and Rotational Electrode Misalignment on a Planar Linear Ion Trap Mass Spectrometer

The performance of miniaturized ion trap mass analyzers is limited, in part, by the accuracy with which electrodes can be fabricated and positioned relative to each other. Alignment of plates in a two-plate planar LIT is ideal to characterize misalignment effects, as it represents the simplest possible case, having only six degrees of freedom (DOF) (three translational and three rotational). High-precision motorized actuators were used to vary the alignment between the two ion trap plates in five DOFs-x, y, z, pitch, and yaw. A comparison between the experiment and previous simulations shows reasonable agreement. Pitch, or the degree to which the plates are parallel along the axial direction, has the largest and sharpest impact to resolving power, with resolving power dropping noticeably with pitch misalignment of a fraction of a degree. Lateral displacement (x) and yaw (rotation of one plate, but plates remain parallel) both have a strong impact on ion ejection efficiency, but little effect on resolving power. The effects of plate spacing (y-displacement) on both resolving power and ion ejection efficiency are attributable to higher-order terms in the trapping field. Varying the DC (axial) trapping potential can elucidate the effects where more misalignments in more than one DOF affect performance. Implications of these results for miniaturized ion traps are discussed. Graphical Abstract ᅟ.

Localized Surface Plasmon Resonance Dependence on Misaligned Truncated Ag Nanoprism Dimer

Misaligned edge-to-edge dimers are the common products during the preparation of Ag nanoprism dimers using self-assembly method. However, in the self-assembly method, Ag nanoprisms are easily truncated because they are easy to oxidize in an acidic environment. In this work, modeling a truncated Ag nanoprism on a misaligned edge-to-edge dimer provides a better understanding of the effects of the truncation and misalignment on localized surface plasmon resonance (LSPR) of the dimer. The resonant wavelength and intensity of the dimer are flexibly modulated by changing the misalignment length of the dimer. As the misalignment length increases, a stronger peak at the shorter wavelength and a weaker one at the longer wavelength are observed. The resonant wavelengths and intensities of the two peaks are also flexibly tuned by adjusting the truncated length of the Ag nanoprism in the dimer. The results are numerically demonstrated based on the finite element method (FEM) and show promising potential for nanoswitch, multi-channel tunable biosensor and other nanodevice applications.

An optical alignment system improves precision of soluble aggregate quantitation by sedimentation velocity analytical ultracentrifugation

Appropriate characterization of soluble aggregates is an important aspect of biologics development and manufacturing, and sedimentation velocity analytical ultracentrifugation (SV-AUC) is often used an orthogonal technique to size-exclusion chromatography (SEC) for this purpose. Precise quantification of low levels of soluble aggregates by SV-AUC can be adversely impacted by improper cell alignment. This report describes the development of an optical system capable of quantifying cell alignment that affords a substantial improvement compared to historical approaches.

Misalignment between physicians and patient satisfaction with psoriatic arthritis disease control

The main objective of the present study is to evaluate the misalignment between psoriatic arthritis (PsA) patient- and physician-reported satisfaction with PsA control. Data came from the Adelphi Rheumatology Disease Specific Programme, a retrospective, cross-sectional survey of US-based rheumatologists and patients. Physicians provided satisfaction and clinical characteristics on tender joint count, swollen joint count, and percent body surface area (BSA) affected by psoriasis. Patients provided data on satisfaction, the Work Productivity Activity Impairment and Health Assessment Questionnaire-Disability Index (HAQ-DI) questionnaires. Based on their satisfaction response, patient-physician pairs were classified into aligned (both satisfied or dissatisfied) or misaligned (rated satisfaction differently) groups. Multivariate analysis evaluated association of characteristics with misalignment. Among 305 paired patient-physician records analyzed, 23.6% were misaligned and 76.4% were aligned. The misaligned group had shorter disease duration (mean years, 5.2 vs. 6.4), used fewer biologic disease-modifying antirheumatic drugs (49.3 vs. 62.9%), had more swollen (mean, 3.7 vs. 1.9, P = 0.0002) and tender joints (mean, 5.6 vs. 2.9, P < 0.0001), greater proportion of patients with comorbidities (72.2 vs. 63.1%), and >3% BSA affected by psoriatic skin lesions (64.2 vs. 55.1%). Misaligned patients reported greater work impairment (mean, 38.7 vs. 21.4, P = 0.0004), daily activities (mean, 38.7 vs. 22.3, P < 0.0001), and higher disease burden (mean HAQ-DI; 0.56 vs. 0.37, P = 0.0001). Multivariate analysis found the number of swollen joints (P = 0.02) and HAQ-DI score (P = 0.03) was significantly associated with misalignment among all patients; however, not in the subgroup of employed patients. Patient-physician misalignment is associated with increased disease activity and disability among patients with PsA.

Systematic Review of Studies Examining Transtibial Prosthetic Socket Pressures with Changes in Device Alignment

Suitable lower-limb prosthetic sockets must provide an adequate distribution of the pressures created from standing and ambulation. A systematic search for articles reporting socket pressure changes in response to device alignment perturbation was carried out, identifying 11 studies. These were then evaluated using the American Academy of Orthotists and Prosthetists guidelines for a state-of-the-science review. Each study used a design where participants acted as their own controls. Results were available for 52 individuals and five forms of alignment perturbation. Four studies were rated as having moderate internal and external validity, the remainder were considered to have low validity. Significant limitations in study design, reporting quality and in representation of results and the suitability of calculations of statistical significance were evident across articles. Despite the high inhomogeneity of study designs, moderate evidence supports repeatable changes in pressure distribution for specific induced changes in component alignment. However, there also appears to be a significant individual component to alignment responses. Future studies should aim to include greater detail in the presentation of results to better support later meta-analyses.

Structural implications of fenestrated stent graft misalignment

BACKGROUND

Endovascular aneurysm repair is a minimally-invasive method for the treatment of abdominal aortic aneurysms. For aneurysms that involve the visceral arteries, a custom-made stent graft with fenestrations for the branch arteries is required. The purpose of the current study is to evaluate the structural impact of misaligned fenestrations with respect to luminal patency and proximal aortic neck apposition in an in vitro model.

METHODS

A custom apparatus was used to evaluate seven Anaconda and three Zenith fenestrated stent grafts. All stent grafts were evaluated at 10° increments of stent/fenestration misalignment up to 80°. Images were captured at each interval and the luminal cross-sectional area and wall apposition were measured.

RESULTS

The Anaconda stent graft, which has an unsupported main body, demonstrated a linear reduction in luminal patency at increasing angles of misalignment (P < 0.0001). Stent/fenestration misalignments of 20° and 80° resulted in decreases in mean luminal patency of 14% and 54% respectively. The Zenith stent graft demonstrated a similar decrease in luminal patency, starting at misalignments of ≥40° (P < 0.0001). However, with stent/fenestration misalignments of ≥30°, apposition between the Zenith stent graft and the simulated aortic neck was compromised suggesting the creation of a type Ia endoleak.

CONCLUSIONS

Both the Anaconda and Zenith devices behave adversely at extreme angles of misalignment with luminal narrowing in the Anaconda device and loss of wall apposition in the Zenith device; however, both stent grafts appear to be equivalent at low angles of misalignment.

Does the operations of the National Health Insurance Scheme (NHIS) in Ghana align with the goals of Primary Health Care? Perspectives of key stakeholders in northern Ghana

BACKGROUND

In 2005, the World Health Assembly (WHA) of the World Health Organization (WHO) urged member states to aim at achieving affordable universal coverage and access to key promotive, preventive, curative, rehabilitative and palliative health interventions for all their citizens on the basis of equity and solidarity. Since then, some African countries, including Ghana, have taken steps to introduce national health insurance reforms as one of the key strategies towards achieving universal health coverage (UHC). The aim of this study was to get a better understanding of how Ghana's health insurance institutions interact with stakeholders and other health sector programmes in promoting primary health care (PHC). Specifically, the study identified the key areas of misalignment between the operations of the NHIS and that of PHC.

METHODS

Using qualitative and survey methods, this study involved interviews with various stakeholders in six selected districts in the Upper East region of Ghana. The key stakeholders included the National Health Insurance Authority (NHIA), district coordinators of the National Health Insurance Schemes (NHIS), the Ghana Health Service (GHS) and District Health Management Teams (DHMTs) who supervise the district hospitals, health centers/clinics and the Community-based Health and Planning Services (CHPS) compounds as well as other public and private PHC providers. A stakeholders' workshop was organized to validate the preliminary results which provided a platform for stakeholders to deliberate on the key areas of misalignment especially, and to elicit additional information, ideas and responses, comments and recommendations from respondents for the achievement of the goals of UHC and PHC.

RESULTS

The key areas of misalignments identified during this pilot study included: delays in reimbursements of claims for services provided by health care providers, which serves as a disincentive for service providers to support the NHIS; inadequate coordination among stakeholders in PHC delivery; and inadequate funding for PHC, particularly on preventive and promotive services. Other areas are: the bypassing of PHC facilities due to lack of basic services at the PHC level such as laboratory services, as well as proximity to the district hospitals; and finally the lack of clear understanding of the national policy on PHC.

CONCLUSION

This study suggests that despite the progress that has been made since the establishment of the NHIS in Ghana, there are still huge gaps that need urgent attention to ensure that the goals of UHC and PHC are met. The key areas of misalignment identified in this study, particularly on the delays in reimbursements need to be taken seriously. It is also important for more dialogue between the NHIA and service providers to address key concerns in the implementation of the NHIS which is key to achieving UHC.

Does the operations of the National Health Insurance Scheme (NHIS) in Ghana align with the goals of Primary Health Care? Perspectives of key stakeholders in northern Ghana

BACKGROUND

In 2005, the World Health Assembly (WHA) of the World Health Organization (WHO) urged member states to aim at achieving affordable universal coverage and access to key promotive, preventive, curative, rehabilitative and palliative health interventions for all their citizens on the basis of equity and solidarity. Since then, some African countries, including Ghana, have taken steps to introduce national health insurance reforms as one of the key strategies towards achieving universal health coverage (UHC). The aim of this study was to get a better understanding of how Ghana's health insurance institutions interact with stakeholders and other health sector programmes in promoting primary health care (PHC). Specifically, the study identified the key areas of misalignment between the operations of the NHIS and that of PHC.

METHODS

Using qualitative and survey methods, this study involved interviews with various stakeholders in six selected districts in the Upper East region of Ghana. The key stakeholders included the National Health Insurance Authority (NHIA), district coordinators of the National Health Insurance Schemes (NHIS), the Ghana Health Service (GHS) and District Health Management Teams (DHMTs) who supervise the district hospitals, health centers/clinics and the Community-based Health and Planning Services (CHPS) compounds as well as other public and private PHC providers. A stakeholders' workshop was organized to validate the preliminary results which provided a platform for stakeholders to deliberate on the key areas of misalignment especially, and to elicit additional information, ideas and responses, comments and recommendations from participants for the achievement of the goals of UHC and PHC.

RESULTS

The key areas of misalignments identified during this pilot study included: delays in reimbursements of claims for services provided by health care providers, which serves as a disincentive for service providers to support the NHIS, inadequate coordination among stakeholders in PHC delivery; and inadequate funding for PHC, particularly on preventive and promotive services. Other areas are: the bypassing of PHC facilities due to lack of basic services at the PHC level such as laboratory services, as well as proximity to the district hospitals; and finally the lack of clear understanding of the national policy on PHC.

CONCLUSION

This study suggests that despite the progress that has been made since the establishment of the NHIS in Ghana, there are still huge gaps that need urgent attention to ensure that the goals of UHC and PHC are met. The key areas of misalignment identified in this study, particularly on the delays in reimbursements need to be taken seriously. It is also important for more dialogue between the NHIA and service providers to address key concerns in the implementation of the NHIS which is key to achieving UHC.

Long term effects of traffic noise on mortality in the city of Barcelona, 2004-2007

Numerous studies showing statistically significant associations between environmental noise and adverse health effects already exist for short-term (over one day at most) and long-term (over a year or more) noise exposure, both for morbidity and (albeit to a lesser extent) mortality. Recently, several studies have shown this association to be independent from confounders, mainly those of air pollutants. However, what has not been addressed is the problem of misalignment (i.e. the exposure data locations and health outcomes have different spatial locations). Without any explicit control of such misalignment inference is seriously compromised. Our objective is to assess the long-term effects of traffic noise on mortality in the city of Barcelona (Spain) during 2004-2007. We take into account the control of confounding, for both air pollution and socioeconomic factors at a contextual level and, in particular, we explicitly address the problem of misalignment. We employed a case-control design with individual data. We used deaths resulting from myocardial infarction, hypertension, or Type II diabetes mellitus in Barcelona between 2004 and 2007 as cases for the study, while for controls we used deaths (likewise in Barcelona and over the same period of time) resulting from AIDS or external causes (e.g. accidental falls, accidental poisoning by psychotropic drugs, drugs of abuse, suicide and self-harm, or injuries resulting from motor vehicle accidents). The controls were matched with the cases by sex and age. We used the annual average equivalent A-weighted sound pressure levels for daytime (7-21h), evening-time (21-23h) and night-time (23-7h), and controlled for the following confounders: i) air pollutants (NO2, PM10 and benzene), ii) material deprivation (at a census tract level) and iii) land use and other spatial variables. We explicitly controlled for heterogeneity (uneven distribution of both response and environmental exposures within an area), spatial dependency (of the observations of the response variables), temporal trends (long-term behaviour of the response variables) and spatial misalignment (between response and environmental exposure locations). We used a fully Bayesian method, through the Integrated Nested Laplace Approximation (INLA). Specifically, we plugged the whole model for the exposure into the health model and obtained a linear predictor defined on the entire spatial domain. Separate analyses were carried out for men and for women. After adjusting for confounders, we found that traffic noise was associated with myocardial infarction mortality along with Type II diabetes mellitus in men (in both cases, odds ratios (OR) were around 1.02) and mortality from hypertension in women (ORs around 1.01). Nevertheless, only in the case of hypertension in women, does the association remain statistically significant for all age groups considered (all ages, ≥65 years and ≥75 years).

Dynamic torsional misalignment of eyes during laser in-situ keratomileusis

PURPOSE

To determine the amount and characteristics of dynamic torsional misalignment of eyes during excimer ablation in laser in-situ keratomileusis (LASIK).

METHODS

Retrospective trial for evaluation of dynamic intraoperative torsional misalignment of 179 eyes that underwent LASIK for correction of myopia and/or astigmatism. Patients were treated with the Keracor 217z excimer laser implementing 25 Hz dynamic eye tracker ACE 100 (both Technolas Perfect Vision, Munich, Germany). From dynamic torsional misalignments, temporal power spectra were obtained by Fourier analysis up to a frequency of 12.5 Hz and an amplitude of ±15° from initial torsional status (limited by the tracking system). The f90, f95, and f99 criteria were defined as the frequency below which 90 %, 95 %, and 99 % of misalignments occur. A Wilcoxon rank sum test was performed to detect differences of f90, f95, and f99 in groups' gender, age, and eye (if both eyes underwent surgery at same day). Multiple regression analysis (MRA) was performed to evaluate possible preoperative predictors of f90, f95, and f99.

RESULTS

Fourier analysis showed a dominance of high-frequency, low-power dynamic torsional misalignment. Mean f95 threshold of rotational movements was 4.89±2.12 Hz (median 4.54, ranging from 0.44 to 9.23 Hz). Wilcoxon rank sum test showed no differences in f90, f95, and f99 between groups' gender, age, and eye. MRA revealed age, gender, and optical zone as preoperative predictors on intraoperative f90, f95, and f99.

CONCLUSIONS

Dynamic intraoperative torsional misalignments of eyes undergoing LASIK are dominated by low-frequency (slow), high-power (large) movements, with 95 % being slower than 4.89Hz regarding the spectrum analyzed (0-12.5Hz, ±15°). Movements can be predicted preoperatively by eye treated, patients' gender, and age in pre-LASIK diagnostics.

Effect of misalignment of air-coupled probes on Ao Lamb mode propagating in a metal plate

Proper alignment of air-coupled ultrasonic transducers for generation and reception of Lamb waves is vital in order to acquire a high amplitude wave group. Any misalignment with either the transmitter or the receiver or both adversely influences the amplitude of a Lamb mode. This paper reports a systematic attempt to quantify the reduction in the amplitude of the fundamental anti-symmetric Lamb mode (Ao) in a metal plate caused by misalignments in air-coupled probes. Three different types of misalignments - linear, orientation and synchronised orientation were deliberately introduced in the transducers, and experiments were performed on a 6mm thick aluminium plate. Amplitudes of Ao mode measured at various configurations were normalised with that of Ao mode, captured in a reference configuration. Suitable curves fitted over the experimental data points revealed that Gaussian curves represent appropriately the variations in normalised amplitudes of Ao mode. Moreover, analytical expressions were derived to predict the difference in arrival times of Lamb mode(s) due to orientation and synchronised orientation misalignments.

Evaluating the effect of splitting cylindrical power on improving patient tolerance to toric lens misalignment

PURPOSE

Evaluating the impact of splitting toric power on patient tolerance to misorientation such as with intraocular lens rotation.

SETTING

University vision clinic.

METHODS

Healthy, non astigmats had +1.50D astigmatism induced with spectacle lenses at 90°, 135°, 180° and +3.00D at 90°. Two correcting cylindrical lenses of the opposite sign and half the power each were subsequently added to the trial frame misaligned by 0°, 5° or 10° in a random order and misorientated from the initial axis in a clockwise direction by up to 15° in 5° steps. A second group of adapted astigmats with between 1.00 and 3.00DC had their astigmatism corrected with two toric spectacle lenses of half the power separated by 0°, 5° or 10° and misorientated from the initial axis in both directions by up to 15° in 5° steps. Distance, high contrast visual acuity was measured using a computerised test chart at each lens misalignment and misorientation.

RESULTS

Misorientation of the split toric lenses caused a statistically significant drop in visual acuity (F=70.341; p<0.001). Comparatively better acuities were observed around 180°, as anticipated (F=3.775; p=0.035). Misaligning the split toric power produced no benefit in visual acuity retention with axis misorientation when subjects had astigmatism induced with a low (F=2.190, p=0.129) or high cylinder (F=0.491, p=0.617) or in the adapted astigmats (F=0.120, p=0.887).

CONCLUSION

Misalignment of toric lens power split across the front and back lens surfaces had no beneficial effect on distance visual acuity, but also no negative effect.

Effects of misalignment on static torsional strength of anterior cervical plate systems

BACKGROUND CONTEXT

There is little understanding of cervical plate misalignment as a risk factor for plate failure at the plate-screw-bone interface.

PURPOSE

To assess the torsional strength and mode of failure of cervical plates misaligned relative to the midsagittal vertical axis.

STUDY DESIGN

Plastic and foam model spine segments were tested using static compression and torsion to assess effects of misaligned and various lengths anterior cervical plate (ACPs).

METHODS

Different length ACPs and cancellous fixed angle screws underwent axial torsional testing on a servo-hydraulic test frame at a rate of 0.5°/s. A construct consisted of one ACP, four screws, one ultrahigh-molecular weight polyethylene inferior block, and one polyurethane foam superior block. Group 1 had ACPs aligned in the midsagittal vertical axis, group 2 plates were positioned 20° offset from the midline, and group 3 had the ACP shifted 5 mm away and 20° offset from midline. Torques versus angle data were recorded. The failure criterion was the first sign of pullout determined visually and graphically.

RESULTS

Group 1 had a more direct screw pullout during failure. For the misaligned plates, failure was a combination of the screws elongating the holes and shear forces acting between the plate and block. The misaligned plates needed more torque to failure. The failure torque was 50% reduced for the longer versus the shorter plates in the neutral position. Graphically shown initial screw slippage inside the block preceded visual identification of slippage in some cases.

CONCLUSIONS

We observed different failure mechanisms for neutral versus misaligned plates. Clinically, misalignment may have the benefit of needing more torque to fail. Misalignment was a risk factor for failure of the screw-bone interface, especially in longer plate constructs. These comparisons of angulations may be a solid platform for expansion toward a more applicable in vivo model.