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1.
Int Urogynecol J ; 35(7): 1375-1379, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38700729

ABSTRACT

Overactive bladder (OAB) is a highly prevalent condition with significant associated comorbidities. Current management guidelines suggest the utilization of anticholinergic medication as a second line after nonpharmacological treatment. Tibial nerve stimulation (TNS), which has previously been thought to have been expensive and inaccessible, was relegated to a third-line therapy. However, given the recently discovered association between anticholinergic medication use and dementia as well as the recent FDA approval of transcutaneous tibial nerve stimulation (TTNS), there may be a need to revisit management guidelines. In this commentary, we identify the two types of TNS, percutaneous tibial nerve stimulation (PTNS) and TTNS and compare them with anticholinergics. By considering their respective efficacies, side-effects profiles, and associated costs, we make the case in this commentary for an update to guidelines that includes TNS as second-line OAB management ahead of anticholinergic medication.


Subject(s)
Cholinergic Antagonists , Tibial Nerve , Transcutaneous Electric Nerve Stimulation , Urinary Bladder, Overactive , Urinary Bladder, Overactive/therapy , Urinary Bladder, Overactive/drug therapy , Humans , Cholinergic Antagonists/adverse effects , Cholinergic Antagonists/therapeutic use , Female , Practice Guidelines as Topic
3.
Nature ; 625(7995): 476-482, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38233616

ABSTRACT

Proving mathematical theorems at the olympiad level represents a notable milestone in human-level automated reasoning1-4, owing to their reputed difficulty among the world's best talents in pre-university mathematics. Current machine-learning approaches, however, are not applicable to most mathematical domains owing to the high cost of translating human proofs into machine-verifiable format. The problem is even worse for geometry because of its unique translation challenges1,5, resulting in severe scarcity of training data. We propose AlphaGeometry, a theorem prover for Euclidean plane geometry that sidesteps the need for human demonstrations by synthesizing millions of theorems and proofs across different levels of complexity. AlphaGeometry is a neuro-symbolic system that uses a neural language model, trained from scratch on our large-scale synthetic data, to guide a symbolic deduction engine through infinite branching points in challenging problems. On a test set of 30 latest olympiad-level problems, AlphaGeometry solves 25, outperforming the previous best method that only solves ten problems and approaching the performance of an average International Mathematical Olympiad (IMO) gold medallist. Notably, AlphaGeometry produces human-readable proofs, solves all geometry problems in the IMO 2000 and 2015 under human expert evaluation and discovers a generalized version of a translated IMO theorem in 2004.


Subject(s)
Mathematics , Natural Language Processing , Problem Solving , Humans , Mathematics/methods , Mathematics/standards
4.
Public Health ; 224: 20-25, 2023 Sep 09.
Article in English | MEDLINE | ID: mdl-37696198

ABSTRACT

OBJECTIVES: Individuals living in group homes during the COVID-19 pandemic faced unique challenges and health risks related to living in shared spaces. This study aimed to assess the experiences of living and working in a group home during the pandemic and to explore the role of the built environment. STUDY DESIGN AND METHODS: We conducted longitudinal working groups with group home residents with intellectual and developmental disabilities and serious mental illness, group home staff, and families/caregivers of residents from December 2020 through December 2022. Common themes highlighting ways in which group home residents, staff, and caregivers perceived the built environment to impact living in a group home during the COVID-19 pandemic were identified. RESULTS: Resonant themes centered around increased risk of COVID-19 infection, ad hoc spatial adaptations for infection control, space-related challenges due to isolation and quarantine requirements, and limited access to public spaces. CONCLUSION: Group home residents and staff experienced multiple health and wellness challenges during the COVID-19 pandemic related to their surrounding built environment. Mechanisms to engage group home residents in modifications of their built environment may improve the effectiveness of infection control policies while acknowledging individual autonomy.

5.
Swiss Med Wkly ; 150: w20347, 2020 Sep 21.
Article in English | MEDLINE | ID: mdl-33038261

ABSTRACT

BACKGROUND: There is currently no consensus on the ideal approach for the operative treatment of Morton’s neuroma. The distal transverse plantar approach aims at optimal exposure without the scar complications associated with the longitudinal plantar approach. Long-term evaluation based on validated outcome instruments is lacking. The main purpose of this retrospective study was to evaluate the long-term clinical outcome of this approach using validated function and scar evaluation scores. METHODS: Forty-nine patients operated on at our institution were examined clinically by two independent observers using the Foot and Ankle Ability Measure (FAAM) and the Vancouver Scar Scale (VSS). Patients who underwent neurectomy alone and those who had additional foot surgery were compared. RESULTS: Assessment at a mean of 7.9 years (range 4–12) postoperatively revealed a mean FAAM score of 84.8 ± 25% and a mean VSS score of 1.57 ± 1.7. Patients who underwent neurectomy alone had higher FAAM scores at follow up. We observed no complication that required an additional procedure. CONCLUSIONS: The transverse plantar approach results in good objective outcome scores, including scar healing, in the long term. This is our preferred technique because, in our experience, it offers optimal visualisation of the nerve, does not require deep dissection and allows the exposure of two adjacent web spaces of the foot through a single incision.


Subject(s)
Morton Neuroma , Neuroma , Humans , Morton Neuroma/surgery , Neuroma/surgery , Retrospective Studies
6.
AJNR Am J Neuroradiol ; 41(10): 1809-1815, 2020 10.
Article in English | MEDLINE | ID: mdl-32855193

ABSTRACT

BACKGROUND AND PURPOSE: When mapping the ischemic core and penumbra in patients with acute ischemic stroke using perfusion imaging, the core is currently delineated by applying the same threshold value for relative CBF at all time points from onset to imaging. We investigated whether the degree of perfusion abnormality and optimal perfusion parameter thresholds for defining ischemic core vary with time from onset to imaging. MATERIALS AND METHODS: In a prospectively maintained registry, consecutive patients were analyzed who had ICA or M1 occlusion, baseline perfusion and diffusion MR imaging, treatment with IV tPA and/or endovascular thrombectomy, and a witnessed, well-documented time of onset. Ten superficial and deep MCA ROIs were analyzed in ADC and perfusion-weighted images. RESULTS: Among the 66 patients meeting entry criteria, onset-to-imaging time was 162 minutes (range, 94-326 minutes). Of the 660 ROIs analyzed, 164 (24.8%) showed severely or moderately reduced ADC (ADC ≤ 620, ischemic core), and 496 (75.2%), mildly reduced or normal ADC (ADC > 620). In ischemic core ADC regions, longer onset-to-imaging times were associated with more highly abnormal perfusion parameters-relative CBF: Spearman correlation, r = -0.22, P = .005; relative CBV: r = -0.41, P < .001; MTT: - r = -0.29, P < .001; and time-to-maximum: r = 0.35, P < .001. As onset-to-imaging times increased, the best cutoff values for relative CBF and relative CBV to discriminate core from noncore tissue became progressively lower and overall accuracy of the core tissue definition increased. CONCLUSIONS: Perfusion abnormalities in ischemic core regions become progressively more abnormal with longer intervals from onset to imaging. Perfusion parameter value thresholds that best delineate ischemic core are more severely abnormal and have higher accuracy with longer onset-to-imaging times.


Subject(s)
Ischemic Stroke/diagnostic imaging , Perfusion Imaging/methods , Aged , Aged, 80 and over , Diffusion Magnetic Resonance Imaging/methods , Female , Humans , Image Interpretation, Computer-Assisted/methods , Ischemic Stroke/pathology , Male , Middle Aged
7.
J Wrist Surg ; 9(4): 321-327, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32760611

ABSTRACT

Background Dart-throwing motion (DTM) is an important functional arc of the wrist from radial extension to ulna flexion. An aim of partial fusion surgery of the wrist is to maintain maximal functional motion while addressing the pathology. The radioscapholunate (RSL) fusion, accompanied with partial resection of the distal scaphoid, is thought to allow better DTM than other partial wrist fusions such as the four-corner fusion (4CF). Question Does an RSL fusion allow better functional DTM than 4CF, and how does this range compare with healthy wrists and the patient's contralateral wrist? Patients and Methods Patients who have undergone an RSL fusion or 4CF at our tertiary center were identified and invited to present to have their DTM arc measured. To accurately measure DTM, a previously validated inertial measurement device was used. Patient's functional DTM arc was measured in both unrestrained (elbow and shoulder free to move) and restrained (elbow and shoulder immobilized) fashions. This was compared with their contralateral wrist and a group of healthy control volunteers. Results Overall five RSL fusions, 10 4CF and 24 control patients were enrolled in the study. There was no significant difference between functional DTM when 4CF and RSL fusion were compared. Both had significantly reduced functional DTM arc than control patients. There was no significant difference between the operated wrist compared with the patient's contralateral unoperated wrist. Conclusion RSL fusion is not significantly better at maintaining functional DTM when compared with 4CF. Both surgeries result in decreased functional DTM arc when compared with control patients. This is a cohort study and reflects a level of evidence IV. Level of Evidence This is a Leve IV, cohort study.

8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 5790-5793, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30441651

ABSTRACT

Recently, numerous comprehensive studies have been concentrating on the intricate kinematics of the wrist joint functionality captured with dart thrower's movement. It is envisaged that the wrist capability in performing daily activities can be more accurately characterized or encapsulated in the dart thrower's movement. This study examines the characteristic function of wrist movements during dart-throwing motion using only gyroscopic data measured from inertial sensors. A multi-dimensional form of dart throwing trajectory is described using quaternion representation associated with distance metric to quantitatively validate the functional wrist performance between two cohorts; healthy controls and patients. Eight normal subjects and eight patients engaged in a series of clinical trials conducted after undergoing post-surgical reconstructive procedures of the wrist joint. The discriminative results in terms of silhouette clustering evaluation show that the use of distance metric values based quaternion trajectory is well-matched consistently with subjective expert assessments. Our proposed approach captures the relative motions underpinning the wrist joint instead of relying on the traditional measure based on the range of motion measure. Therefore, this paper proposes a reliable approach to dynamically capture the wrist functionality during dart thrower's movement; a movement envisaged to describe the ability to engage in daily life activities. These quantitative outcomes in terms of measurement consistency will provide insightful information in understanding the significant changes in wrist joint signatures associated with various scenarios.


Subject(s)
Physical Functional Performance , Wrist/physiology , Biomechanical Phenomena , Humans , Movement , Range of Motion, Articular , Wrist Joint/physiology
9.
Opt Lett ; 42(6): 1084-1087, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-28295098

ABSTRACT

The large-scale and low-cost fabrication of high sensitivity sensors for the real-time detection of biochemicals and molecular substances opens up new opportunities in the areas of bioanalytic screening and medical diagnostics. Planar integrated photonic resonators that can be fabricated with a low footprint, in spatial and wavelength multiplexed arrangements, and that enable integration with microfluidics on the wafer scale have emerged as a promising sensing platform for these application fields. We realized an optofluidic and label-free biosensor that is based on hydrogenated amorphous silicon microring resonators embedded in silicon/glass microfluidic channels for analyte injection and biomolecule immobilization. The optofluidic sensor merits for refractive index and biomolecule sensing are evaluated by sensitivity and detection limit simulations, whereas a proof of concept is demonstrated by real-time protein immobilization experiments of functionalized resonators.

10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 4589-4592, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28269297

ABSTRACT

Describing the flexibility of the hand using the reachable space concept has drawn the attention of many researchers in recent years. Existing approaches involving numerical techniques to obtain the reachable space are generally computationally expensive. In this study, we propose a resource-friendly approach to determine and quantify the bidimensional reachable space of the finger. The fundamental idea of the approach connects to a set of arc formulae for the boundary of the reachable space. These formulae of the boundary result a unique description to calculate the area of the reachable space using Green's theorem. Adopting this novel approach, reachable spaces can be visualised and quantified to effectively evaluate the functionality of different subjects and their therapeutic conditions. We evaluated the performance of the proposed approach against the popular kinematic feedforward approach and Monte Carlo simulation separately. The exclusive description of the reachable space boundary resulted in significant improvement to the execution time while delivering more accurate quantification values.


Subject(s)
Fingers/physiology , Range of Motion, Articular/physiology , Adult , Biomechanical Phenomena , Humans , Male , Monte Carlo Method , Task Performance and Analysis
11.
Article in English | MEDLINE | ID: mdl-19164033

ABSTRACT

Visual sensations in blind patients suffering from retinal degenerations may be restored by electrical stimulation of retinal neurons using implantable microelectrode arrays. The EPI-RET-3 project was initiated to evaluate a wireless intraocular retinal implant system for human use in terms of safety and efficiency. The implant is a remotely controlled fully intraocular prosthesis consisting of a receiver and a stimulator module. The stimulator is placed onto the retina's surface. Data and energy are transmitted via an inductive link from outside the eye to the implant. The EPI-RET-3 device was implanted into six legally blind patients with Retinitis Pigmentosa (RP) for a period of four weeks. The surgery was performed without complications. The implants were activated on days 7, 14 and 27 after implantation. All patients reported visual sensations such as dots, arcs, or lines of different colours and intensities. The required stimulation thresholds were found to be very low. Implantation of the wireless EPI-RET-3 device is safe and the system is suitable to elicit visual sensations in blind RP patients. Major problems in the design and fabrication of a prosthesis for artificial vision could be solved in this approach.


Subject(s)
Artificial Intelligence , Blindness/rehabilitation , Electric Stimulation Therapy/instrumentation , Prostheses and Implants , Retina/physiopathology , Electric Stimulation Therapy/methods , Humans
12.
J Biomed Mater Res ; 43(3): 249-60, 1998.
Article in English | MEDLINE | ID: mdl-9730062

ABSTRACT

A dynamic thermomechanical analysis method was used to determine the values of the viscoelastic parameters, storage modulus (E') and the tangent of the loss angle (tan delta) of samples taken from the near surface and core regions of ultrahigh molecular weight polyethylene (UHMWPE) bar stock specimens that had been aged in ambient laboratory air for 12 months (the control group) and UHMWPE tibial inserts that had been subjected to the following treatments: gamma sterilization followed by shelf aging in ambient laboratory air for between 56 and 112 months or ethylene oxide (EtO) gas sterilization followed by shelf aging in ambient laboratory air for 73 months. Differential scanning calorimetry was used to determine the melt temperature and percentage crystallinity (%C) of these samples. There were three main findings. First, EtO sterilization produced no statistically significant effect on the values of E' or tan delta (relative to those for the control group), but the values of these parameters were markedly affected by gamma sterilization. Second, for gamma-irradiated samples, E' increased with an increase in the shelf aging time. Third, there was a strong direct association between E' and % C. The various potential uses of this association are described, paying special attention to its likely role in predicting the in vivo wear of UHMWPE tibial inserts.


Subject(s)
Biocompatible Materials , Polyethylenes/chemistry , Prostheses and Implants , Tibia , Calorimetry, Differential Scanning , Crystallization , Elasticity , Temperature , Viscosity
13.
Biomaterials ; 19(10): 961-7, 1998 May.
Article in English | MEDLINE | ID: mdl-9690838

ABSTRACT

In cemented arthroplasties, pores are almost invariably present at one or more of the so-called 'weak-link' zones (namely, the bone-cement interface, the cement mantle and the cement-implant interface). In the clinical milieu, arthroplasties are frequently subjected to cyclical loading. These conditions underscore the significance of the apparent fracture toughness (KISR) of the cement. The present work is an investigation of the effect of three variables on KISR of three commercial formulations of bone cement (namely, CMW3, PalacosR and Osteopal) measured using straight-sided chevron notched short rod specimens. For CMW3, the effect of mixing method was studied, with all cement constituents having been stored at ambient laboratory environment prior to being mixed. The highest KISR was obtained from material that was obtained from exposing the cement constituents to a passive vacuum for 20 s and then mixing them in a machine that subjected them to simultaneous mechanical mixing and centrifugation. For Palacos R, the effects of two variables [storage temperature of the cement constituents prior to being mixed (4 degrees C versus 21 degrees C) and mixing method (hand mixing versus vacuum mixing)] (taken individually) were studied. It was found that only mixing method exerts a significant effect on KISR. When room-temperature stored constituents were vacuum mixed, the KISR values for a low-viscosity cement (Osteopal) and a medium-viscosity cement of very similar composition (Palacos R) are not significantly different, indicating that the fracture resistance of bone cement is influenced more by its composition than its viscosity.


Subject(s)
Acrylic Resins/chemistry , Bone Cements/chemistry , Methacrylates/chemistry , Methylmethacrylates/chemistry , Polymethyl Methacrylate/chemistry , Arthroplasty, Replacement, Hip , Biomechanical Phenomena , Bone Cements/standards , Chlorophyll/chemistry , Humans , Methylmethacrylate/chemistry , Viscosity
14.
Biomed Mater Eng ; 8(5-6): 285-98, 1998.
Article in English | MEDLINE | ID: mdl-10081592

ABSTRACT

In light of the time-intensive nature of using real-time shelf-aged specimens in research into property changes of ultra-high-molecular-weight polyethylene (UHMWPE), accelerated thermal diffusion oxidative aging (usually referred to as accelerated aging) is frequently resorted to. A number of such aging protocols have been reported in the literature, with various claims for their producing changes in the properties of the polymer being the same as or similar to those seen in real-time shelf-aged samples. The thrust of the present work is the presentation of a methodology for examining such claims. The methodology is applied to six properties (% crystallinity, melting temperature, oxidation index, ultimate tensile strength, ultimate tensile elongation, and tensile toughness) of 4150HP UHMWPE grade, sterilized using six different methods, prior to and following the use of a specific accelerated aging protocol (oxygen gas at 70 degrees C and 507 kPa pressure; 14 d.). These six properties have been identified in the literature as being strongly correlated with the clinical wear of UHMWPE articular components. It is shown that the claim for the protocol used in the present work (in terms of the simulated equivalent shelf aging time) is plausible. It needs to be emphasized, however, that this conclusion is tentative given the paucity of the relevant literature results that are currently available and which are vital to the application of the methodology.


Subject(s)
Biocompatible Materials/chemistry , Polyethylenes/chemistry , Biocompatible Materials/radiation effects , Calorimetry, Differential Scanning , Chemical Phenomena , Chemistry, Physical , Crystallography , Disinfectants/therapeutic use , Elasticity , Ethylene Oxide/therapeutic use , Gamma Rays/therapeutic use , Hot Temperature , Humans , Joint Prosthesis , Materials Testing , Oxidation-Reduction , Oxygen/administration & dosage , Polyethylenes/radiation effects , Pressure , Prosthesis Design , Sterilization , Tensile Strength , Thermodynamics , Time Factors
15.
J Biomed Mater Res ; 38(3): 221-8, 1997.
Article in English | MEDLINE | ID: mdl-9283967

ABSTRACT

The present study was an investigation of the effect of the method of mixing the constituents of CMW3 bone cement on selected physical and mechanical properties of the fully polymerized cement. Five such methods were used: hand mixing; "active" vacuum mixing; mixing in a machine that allowed simultaneous mechanical mixing and centrifugation; mixing using this machine followed by application of a "passive" vacuum; and application of a passive vacuum followed by mixing in the machine. It was found that the best overall results were obtained from cement that had been mixed using the second and fifth methods and the values of the properties were: density, 1220 to 1246 kg/m3; areal porosity, 0.02 to 7.04%; ultimate compressive strength, 84 to 112 MPa; ultimate compressive strain, 5.1 to 6.4%; and compressive modulus of elasticity, 2249 to 2877 MPa.


Subject(s)
Acrylates/chemistry , Bone Cements/chemistry
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