Breathing motion compensation in chest tomosynthesis: evaluation of the effect on image quality and presence of artifacts.

Purpose: Chest tomosynthesis (CTS) has a relatively longer acquisition time compared with chest X-ray, which may increase the risk of motion artifacts in the reconstructed images. Motion artifacts induced by breathing motion adversely impact the image quality. This study aims to reduce these artifacts by excluding projection images identified with breathing motion prior to the reconstruction of section images and to assess if motion compensation improves overall image quality. Approach: In this study, 2969 CTS examinations were analyzed to identify examinations where breathing motion has occurred using a method based on localizing the diaphragm border in each of the projection images. A trajectory over diaphragm positions was estimated from a second-order polynomial curve fit, and projection images where the diaphragm border deviated from the trajectory were removed before reconstruction. The image quality between motion-compensated and uncompensated examinations was evaluated using the image quality criteria for anatomical structures and image artifacts in a visual grading characteristic (VGC) study. The resulting rating data were statistically analyzed using the software VGC analyzer. Results: A total of 58 examinations were included in this study with breathing motion occurring either at the beginning or end ( n = 17 ) or throughout the entire acquisition ( n = 41 ). In general, no significant difference in image quality or presence of motion artifacts was shown between the motion-compensated and uncompensated examinations. However, motion compensation significantly improved the image quality and reduced the motion artifacts in cases where motion occurred at the beginning or end. In examinations where motion occurred throughout the acquisition, motion compensation led to a significant increase in ripple artifacts and noise. Conclusions: Compensation for respiratory motion in CTS by excluding projection images may improve the image quality if the motion occurs mainly at the beginning or end of the examination. However, the disadvantages of excluding projections may outweigh the benefits of motion compensation.

Magneto-acousto-electrical tomography based on frequency response compensated linearly frequency-modulated signal stimulation.

OBJECTIVE: In magneto-acousto-electrical tomography (MAET), linearly frequency-modulated (LFM) signal stimulation uses much lower peak voltage than the spike pulse stimulation, lengthening the operation life of the transducer. However, due to the uneven frequency responses of the transducer, the low-noise amplifier (LNA), and the bandpass filter (BPF), MAET using LFM signal stimulation suffers from longitudinal resolution loss. In this paper, frequency response compensated linearly frequency-modulated (FRC-LFM) signal stimulation is investigated to resolve the problem. APPROACH: The physical model of measurement of the frequency responses of the transducer and the cascading module of the detection electrodes, the LNA, and the BPF is constructed. The frequency responses are approximated by fitting a curve to the measurement data. The frequency response compensation function is set to the reciprocal of the product of the frequency responses. The digital FRC-LFM signal is generated in MATLAB and converted to analog signal through an arbitrary waveform generator. Two groups of MAET experiments are designed to confirm the performance of the FRC-LFM signal stimulation. Pure agar phantom with rectangular through-holes and agar phantom with pork tissue inclusion serve as the samples. MAIN RESULTS: The pulse-compressed magneto-acousto-electrical (MAE) signal obtained using FRC-LFM stimulation has narrower main-lobe than that obtained using LFM excitation,although the signal to noise pulse interference ratio of the former is little lower than that of the latter, which is due to the limitation of the power amplifier. FRC-LFM also proves to be an effective method to utilize the frequency outside the working band of the transducer in MAET. SIGNIFICANCE: The method in this study compensates for the longitudinal resolution loss due to the uneven frequency responses. Combining with high-capability power amplifier and high-performance LNA, the MAET using FRC-LFM signal stimulation can potentially achieve high longitudinal resolution and high sensitivity, advancing MAET toward the clinical application.

EmbB and EmbC regulate the sensitivity of Mycobacterium abscessus to echinomycin.

Treatment of Mycobacterium abscessus (Mab) infections is very challenging due to its intrinsic resistance to most available drugs. Therefore, it is crucial to discover novel anti-Mab drugs. In this study, we explored an intrinsic resistance mechanism through which Mab resists echinomycin (ECH). ECH showed activity against Mab at a minimum inhibitory concentration (MIC) of 2 µg/ml. A ΔembC strain in which the embC gene was knocked out showed hypersensitivity to ECH (MIC: 0.0078-0.0156 µg/ml). The MICs of ECH-resistant strains screened with reference to ΔembC ranged from 0.25 to 1 µg/ml. Mutations in EmbB, including D306A, D306N, R350G, V555I, and G581S, increased the Mab's resistance to ECH when overexpressed in ΔembC individually (MIC: 0.25-0.5 µg/ml). These EmbB mutants, edited using the CRISPR/Cpf1 system, showed heightened resistance to ECH (MIC: 0.25-0.5 µg/ml). The permeability of these Mab strains with edited genes and overexpression was reduced, as evidenced by an ethidium bromide accumulation assay, but it remained significantly higher than that of the parent Mab. In summary, our study demonstrates that ECH exerts potent anti-Mab activity and confirms that EmbB and EmbC are implicated in Mab's sensitivity to ECH. Mutation in EmbB may partially compensate for a loss of EmbC function.

Adaptive impedance control for docking robot via Stewart parallel mechanism.

This paper provides an adaptive impedance control strategy about docking robot, a locking mechanism scheme based on the Stewart platform developing for the problem of excessive collision contact force caused by external environmental interference during autonomous docking tasks of ground unmanned vehicles. First, the docking robot system was introduced, and an inverse kinematics model of the docking robot was constructed. Next, to solve the problem of excessive collision contact force during docking, we have designed an adaptive impedance control algorithm, which includes a steady-state error model of contact force, an adaptive compensation controller design, and system stability analysis, thus achieving active compliance control. Finally, some simulations and experiments were conducted on the docking robot. Compared with traditional impedance control, adaptive impedance control reduces docking collision contact force and achieves compliant control. In the future, the experimental results provide a new docking approach for autonomous docking of unmanned vehicles, and also serve as a reference for the development of intelligent vehicles.

First responders' occupational injury and disease associated with periods of extreme bushfires.

There has been limited research on the health impacts of extreme bushfire exposure among emergency responders (ER) involved in suppressing extreme bushfires. This study aimed to evaluate the associations between extreme bushfires and ER's compensated injury and illness in Victoria, Australia. State-wide ER compensation claims from January 2005 to April 2023 were analysed. Logistic regression modelling was used to identify factors associated with compensation claims during the extreme bushfire periods in 2009 and 2019/20, compared to all other claims, adjusting for seasonality (summer). Of the 44,164 included claims, 1105 (2.5%) had recorded injury/disease onset dates within extreme bushfire periods, and 11,642 (26.4%) occurred in summer months. Over half of claims were made by police (52.4%), followed by ambulance officers/paramedics (27.2%) and firefighters (20.5%). Extreme bushfire period claims were associated with older workers (odds ratio/OR = 1.58,95%CI = 1.30-1.92, ages ≥ 55 vs. 35-44 years). Mental disorders (OR = 1.61,95%CI = 1.25-2.07), intracranial injuries (OR = 3.04,95%CI = 1.69-5.48) and infections/parasites (OR = 3.11,95%CI = 1.61-5.98) vs. wounds were associated with extreme bushfire period claims. Given the expected increase in extreme bushfire events and the ageing workforce, study findings underscore the importance of primary and secondary prevention in ER. This can include periodic health surveillance for older workers, access to early treatment, and ongoing support for mental health conditions.

Silver Nanowire Aerogel Support Promotes Stable Hydrogen Evolution Reaction at High Current Density.

The stability of electrocatalysts during the hydrogen evolution reaction (HER) is vital for efficient production of hydrogen energy. Herein, we demonstrate that silver nanowire aerogel-based support (AABS) could facilitate the construction of HER catalysts with extraordinary long-term stability. A full nanostructure catalyst of nickel phosphide based formed on AABS (Ni2P-Ni5P4@AABS) was prepared to achieve an overpotential of 687 mV (without iR compensation) for HER at the current density of 1 A cm-2 in 0.5 M H2SO4. Excitingly, the stable HER performance was kept for 42 days during the long-term stability (i-t) test at high current density (0.5-1 A cm-2). The excellent HER performance of the Ni2P-Ni5P4@AABS catalyst is attributed to rapid electron transport pathways, numerous more accessible active sites, and support induced enhanced catalytic activity. The support effect was highlighted by a proposed phenomenological two-channel model for electron transport, which provides fresh insights into the design strategy for energy storage and delivery.

Aggregation behavior, interaction forces and physico-chemical parameters of cetyltrimethylammonium chloride in aqueous solution of bovine serum albumin: Impacts of short-chain alcohols and temperature.

To better understand the molecular interactions between cetyltrimethylammonium chloride (CTAC) and bovine serum albumin (BSA), we report the alteration of the physicochemical characteristics of CTAC in aqueous BSA solutions in the presence of different alcohols. The analyses were performed using the conductivity method at temperatures ranging from 298.15 to 323.15 K, with 5 K intervals. The critical micelle concentration (CMC) values of the BSA + CTAC systems were found to change with variations in alcohol type, solvent composition, and temperature. The CMC values grew with the rising alcohol content. The negative free energy changes (∆Gm0) indicated the spontaneous association of the systems in all solvents media. The magnitudes of ∆Hm0 and ∆Sm0, determined from the micellization of the systems, indicated the presence of electrostatic, ion-dipole, and hydrophobic forces. The thermodynamics of transfer (free energy ((∆Gm,tr0), enthalpy (∆Hm,tr0), entropy (∆Sm,tr0)), and compensation parameters (∆Hm0,∗ and Tc)-were also calculated, providing significant insights into the potential interactions between CTAC and BSA in the presence of various alcohol additives. Furthermore, molecular docking studies suggested the binding of CTAC to different BSA binding sites with varying affinities.

Respiration-Induced Organ Motion Compensation: A Review.

PURPOSE: Motion of organs in the abdominal and thoracic cavity caused by respiration is a major issue that affects a wide range of clinical diagnoses or treatment outcomes, including radiotherapy, high-intensity focused ultrasound ablation, and many generalized percutaneous needle interventions. These motions pose significant challenges in accurately reaching the target even for the experienced clinician. METHODS: This review was conducted through comprehensive search on IEEE Explore, Google Scholar, and PubMed. RESULTS: Diverse methods have been proposed to compensate for this motion effect to enable effective surgical operations. This review paper aims to examine the current respiratory motion compensation techniques used across the clinical procedures of radiotherapy, high-intensity focused ultrasound, and percutaneous needle procedures. CONCLUSION: The complexity of respiratory-induced organ motion and diversity of areas for which compensation can be applied allows for a variety of methods to be implemented. This review aims to serve as inspiration for the future development of new systems to achieve clinical relevance.

Nuclear compensatory evolution driven by mito-nuclear incompatibilities.

Mitochondrial function relies on the coordinated expression of mitochondrial and nuclear genes, exhibiting remarkable resilience despite high mitochondrial mutation rates. The nuclear compensation mechanism suggests deleterious mitochondrial alleles drive compensatory nuclear mutations to preserve mito-nuclear compatibility. However, prevalence and factors conditioning this phenomenon remain debated due to its conflicting evidence. Here, we investigate how mito-nuclear incompatibilities impact substitutions in a model for species radiation. Mating success depends on genetic compatibility (nuclear DNA) and spatial proximity. Populations evolve from partially compatible mito-nuclear states, simulating mitochondrial DNA (mtDNA) introgression. Mutations do not confer advantages nor disadvantages, but individual fecundity declines with increasing incompatibilities, selecting for mito-nuclear coordination. We find that selection for mito-nuclear compatibility affects each genome differently based on their initial state. In compatible gene pairs, selection reduces substitutions in both genomes, while in incompatible nuclear genes, it consistently promotes compensation, facilitated by more mismatches. Interestingly, high mitochondrial mutation rates can reduce nuclear compensation by increasing mtDNA rectification, while substitutions in initially compatible nuclear gene are boosted. Finally, the presence of incompatibilities accelerates species radiation, but equilibrium richness is not directly correlated to substitution rates, revealing the complex dynamics triggered by mitochondrial introgression and mito-nuclear coevolution. Our study provides a perspective on nuclear compensation and the role of mito-nuclear incompatibilities in speciation by exploring extreme scenarios and identifying trends that empirical data alone cannot reveal. We emphasize the challenges in detecting these dynamics and propose analyzing specific genomic signatures could shed light on this evolutionary process.

High on sparsity: Interbin compensation of cardiac motion for improved assessment of left-ventricular function using 5D whole-heart MRI.

PURPOSE: Cardiac magnetic resonance is the gold standard for evaluating left-ventricular ejection fraction (LVEF). Standard protocols, however, can be inefficient, facing challenges due to significant operator and patient involvement. Although the free-running framework (FRF) addresses these challenges, the potential of the extensive data it collects remains underutilized. Therefore, we propose to leverage the large amount of data collected by incorporating interbin cardiac motion compensation into FRF (FRF-MC) to improve both image quality and LVEF measurement accuracy, while reducing the sensitivity to user-defined regularization parameters. METHODS: FRF-MC consists of several steps: data acquisition, self-gating signal extraction, deformation field estimations, and motion-resolved reconstruction with interbin cardiac motion compensation. FRF-MC was compared with the original 5D-FRF method using LVEF and several image-quality metrics. The cardiac regularization weight ( λ c $$ {\lambda}_c $$ ) was optimized for both methods by maximizing image quality without compromising LVEF measurement accuracy. Evaluations were performed in numerical simulations and in 9 healthy participants. In vivo images were assessed by blinded expert reviewers and compared with reference standard 2D-cine images. RESULTS: Both in silico and in vivo results revealed that FRF-MC outperformed FRF in terms of image quality and LVEF accuracy. FRF-MC reduced temporal blurring, preserving detailed anatomy even at higher cardiac regularization weights, and led to more accurate LVEF measurements. Optimized λ c $$ {\lambda}_c $$ produced accurate LVEF for both methods compared with the 2D-cine reference (FRF-MC: 0.59% [-7.2%, 6.0%], p = 0.47; FRF: 0.86% [-8.5%, 6.7%], p = 0.36), but FRF-MC resulted in superior image quality (FRF-MC: 2.89 ± 0.58, FRF: 2.11 ± 0.47; p < 10-3). CONCLUSION: Incorporating interbin cardiac motion compensation significantly improved image quality, supported higher cardiac regularization weights without compromising LVEF measurement accuracy, and reduced sensitivity to user-defined regularization parameters.

Psychosocial impacts of post-disaster compensation processes: narrative systematic review.

After disasters, many people seek compensation for physical, psychological or economic damages. However, compensation processes can be perceived as arduous and unfair and potentially create stress for both individuals and communities. This systematic review explored the psychosocial impacts of post-disaster compensation processes, including compensation sought through both litigation and government assistance programmes. We searched seven databases, hand-searched reference lists of included studies, and used thematic analysis to synthesise results of included studies. We screened 6,532 papers, ultimately including 66 in the review. While we found mixed evidence regarding the relationship between individual mental health and the compensation process, many studies suggested the process placed demands on emotional resources and could cause stress. Numerous challenges of the compensation process were described, including complicated paperwork, lengthy processes, inadequate information, confusing eligibility criteria, lack of inter-agency cooperation, poor understanding of communities' unique needs, insufficient pay-outs, and politicisation of the process. Inequities in compensation distribution introduced additional stress to already traumatised communities, who often experienced resentment, envy and conflict. The mixed nature of the relationship between mental health and the compensation process was evident in research trends where a small number of studies reported positive findings related to relating to gratitude, helpfulness of compensation and strengthened community relationships, while a substantial number of others reported negative impacts including higher mental health problems. Positive and negative impacts were reported for both litigation and non-litigation compensation-seeking. The nuanced dynamics of these findings are described in greater detail within the paper. It is important that compensation regulators consider the potential impacts on individuals and communities and take steps to address compensation inequities. This enhanced understanding of how those affected by disasters can rebuild their lives and furthering understanding of how to support them will enable evidence-based approaches to building resilience and planning for long-term recovery. Significant compensation process improvements could be realised by ensuring clear communication and transparent decision-making. Overall, this review underscores the importance of ensuring that compensation processes are fair and straightforward so they can repair material losses without deteriorating the social norms and relationships of affected communities.

Indian Dental Malpractice Claims and Lawsuits: A Medico-Legal Analysis.

Background and Aim: The law of the land assumes that a dentist will always use credible skill, care, and caution in the care of patients. Failing to do something that one is supposed to do (act of omission) or doing something that one is not supposed to do (act of commission) falls under the purview of medical jurisprudence. Each patient is legally entitled to get quality medical care from a physician; failure to such trust is an actionable offense and grievances can be challenged in consumer redressal forums. This analytical study was aimed to study the reasons for dental negligence cases that sought judicial assistance in consumer courts in terms of monetary benefits and also to study the delay in settlements. Materials and Methods: Archival data of final court-pronounced judgment cases on dental negligence between 2018 and 2022 (i.e., 5 years) were gathered from customer forum websites (https://confonet.nic.in, http://indiankanoon.org/doc, and www.casemine.com). A total of 56 proven dental allegation cases were retrieved. In each verdict case, the allegation against dentist by the plaintiff was recorded, and the response to the complaint by the defendant was studied and analyzed. The year of filing the case and date of judgment, basis of compensation awarded, delay in judgment and role of expert evidence appointed by the court assessed. Results: Misdemeanor by serious negligence: 3, slight negligence: 8, negligent injuries: 35, felony of injuries by serious negligence: 10. Conclusion: Because dentistry involves making decisions in unclear scenarios that affect patient care, there is an inherent danger of malpractice litigation. Awareness of medico-legal issues and professional indemnity insurance coverage for the dentist to safeguard himself from negligence, continuous medico-legal training and documentation of records, and adherence to clinical standards for procedures should be emphasized as prior motives to enhance the standard of care, and a basic awareness of how Indian courts resolve disputes would help dentists plan their professional indemnity insurance and operate their profession properly.

Temporal evolution of microstructural integrity in cerebellar peduncles in Parkinson's disease: Stage-specific patterns and dopaminergic correlates.

BACKGROUND: Previous research revealed differences in cerebellar white matter integrity by disease stages, indicating a compensatory role in Parkinson's disease (PD). However, the temporal evolution of cerebellar white matter microstructure in patients with PD (PwPD) remains unclear. OBJECTIVE: To unravel temporal evolution of cerebellar white matter and its dopaminergic correlates in PD. METHODS: We recruited 124 PwPD from the PPMI study. The participants were divided into two subsets: Subset 1 (n = 41) had three MRI scans (baseline, 2 years, and 4 years), and Subset 2 (n = 106) had at least two MRI scans at baseline, 1 year, and/or 2 years. Free water-corrected diffusion metrics were used to measure the microstructural integrity in cerebellar peduncles (CP), the main white matter tracts connecting to and from the cerebellum. The ACAPULCO processing pipeline was used to assess cerebellar lobules volumes. Linear mixed-effect models were used to study longitudinal changes. We also examined the relationships between microstructural integrity in CP, striatal dopamine transporter specific binding ratio (SBR), and clinical symptoms. RESULTS: Microstructural changes in CP showed a non-linear pattern in PwPD. Free water-corrected fractional anisotropy (FAt) increased in the first two years but declined from 2 to 4 years, while free water-corrected mean diffusivity exhibited the opposite trend. The initial increased FAt in CP correlated with cerebellar regional volume atrophy, striatal dopaminergic SBR decline, and worsening clinical symptoms, but this correlation varied across disease stages. CONCLUSIONS: Our findings suggest a non-linear evolution of microstructural integrity in CP throughout the course of PD, indicating the adaptive structural reorganization of the cerebellum simultaneously with progressive striatal dopaminergic degeneration in PD.

Respiratory responses and isocapnic buffering phase in child and youth soccer players during an incremental exercise test.

Purpose: This study investigated the respiratory response and isocapnic buffering (IB) phase during an incremental exercise test to exhaustion in 16 child soccer players (11.9±0.9 years) and 18 youth soccer players (18.2±2.9 years). Methods: The IB phase was calculated as the difference in oxygen uptake (VO2) between the respiratory compensation point (RCP) and metabolic threshold (MT) and expressed in either absolute or relative values. Results: The maximal oxygen uptake (VO2max) was higher in youth players than in child players. For youth players, VO2max was measured at 55.9 ± 3.6 mL min-1 kg-1 and 74.9 ± 4.8 mL min-1 kg-0.75, while for child players, VO2max was 50.8 ± 4.1 mL min-1 kg-1 and 67.2 ± 6.1 mL min-1 kg-0.75 (p < 0.001). MT and RCP occurred at 69.8 ± 6.7% and 90.9 ± 6.9% of VO2max in child players and at 73.9 ± 5.1% and 91.5 ± 4.5% of VO2max in youth players, respectively. The two groups had no significant difference (p > 0.05). Absolute IB (10.6 ± 2.8 vs 9.7 ± 3.1 mL min-1 kg-1), relative IB (23.1 ± 5.7 vs 19.1 ± 6.1), and the ratio of RCP VO2 to MT VO2 (1.3 ± 0.09 vs 1.24 ± 0.09) were similar in child and youth players (p > 0.05). There was no difference in minute ventilation (V̇E, mL min-1 kg-1) and respiratory exchange ratio during exercise between the two groups (p > 0.05). During exercise, respiratory frequency, ventilatory equivalent for carbon dioxide (VE/VCO2) and oxygen (VE/VO2), VE/VCO2 slope, end-tidal O2 pressure were higher in child players than in youth players, while tidal volume (L kg-1), O2 pulse, and end-tidal CO2 pressure were lower (p < 0.05). Conclusion: Despite differences in aerobic capacity and ventilatory response to exercise, child players showed similar IB phase as youth players. Although child players have lower ventilation efficiency than youth players, the higher ventilation response for a given VCO2 may provide an advantage in regulating acid-base balance during intense exercise.

The evolution of gene expression plasticity during adaptation to salt in Chlamydomonas reinhardtii.

When environmental change is rapid or unpredictable, phenotypic plasticity can facilitate adaptation to new or stressful environments to promote population persistence long enough for adaptive evolution to occur. However, the underlying genetic mechanisms that contribute to plasticity and its role in adaptive evolution are generally unknown. Two main opposing hypotheses dominate - genetic compensation and genetic assimilation. Here we predominantly find evidence for genetic compensation over assimilation in adapting the freshwater algae Chlamydomonas reinhardtii to 36g/L salt environments over 500 generations. More canalized genes in the high-salt (HS) lines displayed a pattern of genetic compensation (63%) fixing near or at the ancestral native expression level, rather than genetic assimilation of the salt-induced level, suggesting that compensation was more common during adaptation to salt. Network analysis revealed an enrichment of genes involved in energy production and salt-resistance processes in HS lines, while an increase in DNA repair mechanisms was seen in ancestral strains. In addition, whole-transcriptome similarity amongst ancestral and HS lines displayed the evolution of a similar plastic response to salt conditions in independently reared HS lines. We also found more cis-acting regions in the HS lines; however, the expression patterns of most genes did not mimic that of their inherited sequence. Thus, the expression changes induced via plasticity offer temporary relief, but downstream changes are required for a sustainable solution during the evolutionary process.

Opioid Prescribing Trends Among Workers' Compensation Patients Undergoing Foot and Ankle Surgery.

BACKGROUND: The purpose of this study was to evaluate opioid usage and prescribing trends among workers' compensation (WC) patients who underwent foot or ankle operative procedures compared with a control group. METHODS: A retrospective review was conducted for WC and non-WC patients who underwent foot or ankle procedures in a single academic orthopaedic surgery practice. Outcome measures were total morphine milligram equivalents (MME) and number of opioid prescriptions. RESULTS: A total of 118 patients were identified, including 51 patients in the WC group and 67 in the non-WC group. After index surgery, 67% (34 of 51) of WC patients had 2 or more additional opioid prescriptions compared to 39% (26 of 67) of non-WC patients (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.4-6.7; P = .003). Collectively, there were greater prescriptions of oxycodone MME (P = .002) and hydrocodone MME (P = .07) in the WC cohort. CONCLUSIONS: Workers' compensation patients seem to be prescribed and consume opioids at a higher rate postoperatively. It is important for treating physicians to be aware of these trends, and discussions with patients regarding expected opioid use when planning surgical intervention may be beneficial. Physicians may need to set expectations preoperatively and suggest there are limits on the amount of opioids that can safely be prescribed. LEVEL OF EVIDENCE: Level III, Retrospective cohort study, Prognostic.

Electromyographically controlled prosthetic wrist improves dexterity and reduces compensatory movements without added cognitive load.

Wrist function is a top priority for transradial amputees. However, the combined functional, biomechanical, and cognitive impact of using a powered prosthetic wrist is unclear. Here, we quantify task performance, compensatory movements, and cognitive load while three transradial amputees performed a modified Clothespin Relocation Task using two myoelectric prostheses with and without the wrists. The two myoelectric prostheses include a commercial prosthesis with a built-in powered wrist, and a newly developed inexpensive prosthetic wrist for research purposes, called the "Utah wrist", that can be adapted to work with various sockets and prostheses. For these three participants, task failure rate decreased significantly from 66% ± 12% without the wrist to 39% ± 9% with the Utah wrist. Compensatory forward leaning movements also decreased significantly, from 24.2° ± 2.5 without the wrist to 12.6° ± 1.0 with the Utah wrist, and from 23.6° ± 7.6 to 15.3° ± 7.2 with the commercial prosthesis with an integrated wrist. Compensatory leftward bending movements also significantly decreased, from 20.8° ± 8.6 to 12.3° ± 5.3, for the commercial with an integrated wrist. Importantly, simultaneous myoelectric control of either prosthetic wrist had no significant impact on cognitive load, as assessed by the NASA Task Load Index survey and a secondary detection response task. This work suggests that functional prosthetic wrists can improve dexterity and reduce compensation without significantly increasing cognitive effort. These results, and the introduction of a new inexpensive prosthetic wrist for research purposes, can aid future research and development and guide the prescription of upper-limb prostheses.

An in-phase filter-based flux observation strategy for sensorless control of PMSMs.

Due to the complexity of determining the initial rotor flux and detecting errors, conventional rotor flux observation methods are easily affected by direct current (DC) components and harmonics. To address this issue, this paper proposes an in-phase filter (IPF)-based rotor flux observation strategy for sensorless control of permanent magnet synchronous machines (PMSMs). The core components of the IPF consist of a double second-order generalized integrator (DSOGI) and a phase angle compensation transfer function (PACTF). The DSOGI provides a accurate electrical angular frequency, while the PACTF implements a phase correction to the vq' signals. By employing IPF structure, accurate observations for rotor flux, electronic speed, and rotor position are achieved, which can be effectively used in the sensorless control of PMSMs, eliminating the need for magnitude and phase compensations. Finally, the proposed observation strategy is applied to an experimental bench of a PMSM, and its effectiveness is illustrated by experimental results. From experimental results, it can be concluded that the IPF is significantly better than the LPF, and 5% more accurate than the observer based on cascade second-order generalized integral(CSOGI) overall.

The Reindeer Circadian Clock Is Rhythmic and Temperature-compensated But Shows Evidence of Weak Coupling Between the Secondary and Core Molecular Clock Loops.

Circadian rhythms synchronize the internal physiology of animals allowing them to anticipate daily changes in their environment. Arctic habitats may diminish the selective advantages of circadian rhythmicity by relaxing daily rhythmic environmental constraints, presenting a valuable opportunity to study the evolution of circadian rhythms. In reindeer, circadian control of locomotor activity and melatonin release is weak or absent, and the molecular clockwork is reportedly non-functional. Here we present new evidence that the circadian clock in cultured reindeer fibroblasts is rhythmic and temperature-compensated. Compared with mouse fibroblasts, however, reindeer fibroblasts have a short free-running period, and temperature cycles have an atypical impact on clock gene regulation. In reindeer cells, Per2 and Bmal1 reporters show rapid responses to temperature cycles, with a disintegration of their normal antiphasic relationship. The antiphasic Per2-Bmal1 relationship re-emerges immediately after release from temperature cycles, but without complete temperature entrainment and with a marked decline in circadian amplitude. Experiments using Bmal1 promoter reporters with mutated RORE sites showed that a reindeer-like response to temperature cycles can be mimicked in mouse or human cell lines by decoupling Bmal1 reporter activity from ROR/REV-ERB-dependent transcriptional regulation. We suggest that weak coupling between core and secondary circadian feedback loops accounts for the observed behavior of reindeer fibroblasts in vitro. Our findings highlight diversity in how the thermal environment affects the temporal organization of mammals living under different thermoenergetic constraints.

Navigating Nephrology's Decline Through a GPT-4 Analysis of Internal Medicine Specialties in the United States: Qualitative Study.

Background: The 2024 Nephrology fellowship match data show the declining interest in nephrology in the United States, with an 11% drop in candidates and a mere 66% (321/488) of positions filled. Objective: The study aims to discern the factors influencing this trend using ChatGPT, a leading chatbot model, for insights into the comparative appeal of nephrology versus other internal medicine specialties. Methods: Using the GPT-4 model, the study compared nephrology with 13 other internal medicine specialties, evaluating each on 7 criteria including intellectual complexity, work-life balance, procedural involvement, research opportunities, patient relationships, career demand, and financial compensation. Each criterion was assigned scores from 1 to 10, with the cumulative score determining the ranking. The approach included counteracting potential bias by instructing GPT-4 to favor other specialties over nephrology in reverse scenarios. Results: GPT-4 ranked nephrology only above sleep medicine. While nephrology scored higher than hospice and palliative medicine, it fell short in key criteria such as work-life balance, patient relationships, and career demand. When examining the percentage of filled positions in the 2024 appointment year match, nephrology's filled rate was 66%, only higher than the 45% (155/348) filled rate of geriatric medicine. Nephrology's score decreased by 4%-14% in 5 criteria including intellectual challenge and complexity, procedural involvement, career opportunity and demand, research and academic opportunities, and financial compensation. Conclusions: ChatGPT does not favor nephrology over most internal medicine specialties, highlighting its diminishing appeal as a career choice. This trend raises significant concerns, especially considering the overall physician shortage, and prompts a reevaluation of factors affecting specialty choice among medical residents.