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1.
Orthop Surg ; 16(1): 276-281, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37986662

ABSTRACT

Improper acetabulum component position is a significant risk factor for postoperative dislocation after total hip arthroplasty. Several radiographic two-dimensional methods exist for measuring acetabulum component anteversion, but they cannot distinguish between anteversion and retroversion. "Liaw's version," initially proposed as a simple mathematical standardized two-dimensional method, was modified to the computerized ellipse method, proving superior accuracy to traditional two-dimensional methods. In this article, we demonstrated its application in detecting and measuring retroverted acetabulum component. We obtained anteroposterior pelvis radiographs from a patient undergoing total hip arthroplasty on the day of surgery and 2 weeks postoperatively. The computerized ellipse method was used to measure the acetabulum component orientation. Upon comparison, the difference between θ assigned to be retroverted (9.52-8.56 = 0.96) is much smaller than the difference between θ assigned to be anteverted (23.81-18.86 = 4.95), leading us to determine retroversion. This was further confirmed by computed tomography at the 6-week follow-up. We propose that using the computerized ellipse method to measure Liaw's version can be a valuable tool in identifying acetabulum component retroversion on anteroposterior radiographs during routine postoperative follow-up and retrospective assessments of total hip arthroplasty patients.


Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Humans , Acetabulum/diagnostic imaging , Acetabulum/surgery , Retrospective Studies , Radiography , Arthroplasty, Replacement, Hip/methods
4.
Orthop J Sports Med ; 11(1): 23259671221142242, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36636031

ABSTRACT

Background: Single-row (SR) and double-row repair techniques have been described to treat rotator cuff tears. We present a novel surgical strategy of arthroscopic-assisted mini-open repair in which a locking-loop suture bridge (LLSB) is used. Purpose: To compare the functional outcomes and repair integrity of LLSB technique to the SR technique for arthroscopic-assisted mini-open repair of small to medium rotator cuff tears. Study Design: Cohort study; Level of evidence, 3. Methods: Included were 39 patients who underwent LLSB repair (LLSB group) and 44 patients who underwent SR suture anchor repair (SR group) from 2015 to 2018. We evaluated all patients preoperatively and at 3, 6, 12, and 24 months postoperatively using the visual analog scale (VAS) for pain, Oxford Shoulder Score (OSS), and American Shoulder and Elbow Surgeons (ASES) score. Also, shoulder sonography was performed at 12 months postoperatively to evaluate repair integrity using the Sugaya classification system. The independent-sample t test was used to analyze functional outcomes (VAS, OSS, and ASES scores), and the Fisher exact test was used to analyze postoperative sonography results. Results: Patients in both the LLSB and SR groups saw a significant improvement on all 3 outcome measures from preoperatively to 24 months postoperatively (P < .001 for all). However, when comparing scores between groups, only the scores at 3 months postoperatively differed significantly (VAS: P = .002; OSS: P < .001; ASES: P = .005). Shoulder sonography at 12 months postoperatively revealed no significant difference in repair integrity between the LLSB and SR groups (retear rate: 10.26% and 6.82%, respectively; P = .892). Conclusion: Better outcome scores were seen at 3-month follow-up in the LLSB group, with no difference in retear rates compared with the SR group at 12 months postoperatively. The LLSB technique was found to be a reliable technique for rotator cuff repair of small- to medium-sized tears.

5.
Auris Nasus Larynx ; 48(1): 116-123, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32727703

ABSTRACT

OBJECTIVE: Tongue strength is crucial for safe and efficient oropharyngeal swallowing. This study examined the effect of tongue-to-palate resistance training (TPRT) on anterior and posterior tongue strength by conducting a prospective, randomized, parallel allocation trial. METHODS: Ninety-one healthy adults were recruited in this study and were randomly assigned to an experimental group (n = 44) or a control group (n = 47). The experimental group performed TPRT for 8 weeks (5 days per week), whereas the control group performed the usual daily activities. Tongue strength was measured using the Iowa Oral Performance Instrument (IOPI) before and after the practice program was conducted at weeks 2, 4, 6, and 8, to evaluate the feasibility of the developed training protocol. RESULTS: This experimental group demonstrated more improvements in both anterior tongue strength (p < .05) and posterior tongue strength (p < .05). The positive effects of the intervention on tongue strength appeared at 8 weeks for the anterior region and 2 weeks for the posterior region. CONCLUSIONS: These findings illustrate that TPRT can improve tongue strength. It is suggested that people integrate this exercise protocol into their daily life, positive change in tongue strength may prevent or halt presbyphagia.


Subject(s)
Resistance Training/methods , Tongue/physiology , Adult , Aged , Analysis of Variance , Deglutition/physiology , Deglutition Disorders/prevention & control , Female , Healthy Volunteers , Humans , Male , Middle Aged , Palate , Prospective Studies , Reproducibility of Results
6.
Sci Adv ; 5(11): eaax4424, 2019 11.
Article in English | MEDLINE | ID: mdl-31819900

ABSTRACT

The past few years have witnessed rapid advances in the synthesis of high-quality perovskite nanocrystals (PNCs). However, despite the impressive developments, the stability of PNCs remains a substantial challenge. The ability to reliably improve stability of PNCs while retaining their individual nanometer size represents a critical step that underpins future advances in optoelectronic applications. Here, we report an unconventional strategy for crafting dual-shelled PNCs (i.e., polymer-ligated perovskite/SiO2 core/shell NCs) with exquisite control over dimensions, surface chemistry, and stabilities. In stark contrast to conventional methods, our strategy relies on capitalizing on judiciously designed star-like copolymers as nanoreactors to render the growth of core/shell NCs with controlled yet tunable perovskite core diameter, SiO2 shell thickness, and surface chemistry. Consequently, the resulting polymer-tethered perovskite/SiO2 core/shell NCs display concurrently a stellar set of substantially improved stabilities (i.e., colloidal stability, chemical composition stability, photostability, water stability), while having appealing solution processability, which are unattainable by conventional methods.

7.
Nano Lett ; 19(9): 6049-6057, 2019 Sep 11.
Article in English | MEDLINE | ID: mdl-31373501

ABSTRACT

Whispering gallery mode resonators have been demonstrated to be a great way to achieve superior optical cavities with high quality factor and small mode volume. However, due to the high sensitivity of these modes to the properties of the resonator boundary, they are susceptible to parasitic splitting of clockwise and counterclockwise modes. In this work, we investigate the effect of implantation of an engineered notch into the boundary of a circular microdisk resonator fabricated from colloidal quantum dots, which are particularly sensitive to boundary defects. We observed a strong reduction of parasitic mode splitting with introduction of a large engineered notch, as well as enhanced directionality of laser emission. We further investigate the performance of these resonators in evanescently coupled pairs, where the modal interaction allows modulation of laser behavior through variation of the gain and loss induced by the optical pump. We show that two distinct cases of modal interaction can be achieved by adjusting the size of the engineered notch, providing a bridge between intra- and interdisk modal interactions for laser spectral control.

8.
Adv Mater ; 31(32): e1901602, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31192498

ABSTRACT

Instability of perovskite quantum dots (QDs) toward humidity remains one of the major obstacles for their long-term use in optoelectronic devices. Herein, a general amphiphilic star-like block copolymer nanoreactor strategy for in situ crafting a set of hairy perovskite QDs with precisely tunable size and exceptionally high water and colloidal stabilities is presented. The selective partition of precursors within the compartment occupied by inner hydrophilic blocks of star-like diblock copolymers imparts in situ formation of robust hairy perovskite QDs permanently ligated by outer hydrophobic blocks via coprecipitation in nonpolar solvent. These size- and composition-tunable perovskite QDs reveal impressive water and colloidal stabilities as the surface of QDs is intimately and permanently ligated by a layer of outer hydrophobic polymer hairs. More intriguingly, the readily alterable length of outer hydrophobic polymers renders the remarkable control over the stability enhancement of hairy perovskite QDs.

9.
Nat Commun ; 10(1): 561, 2019 02 04.
Article in English | MEDLINE | ID: mdl-30718515

ABSTRACT

Evanescently coupled pairs of microdisk lasers have emerged as a useful platform for studying the non-Hermitian physics of exceptional points. It remains an open question how scalable and versatile such phenomena can be when carried over to other designs. Here we have studied the effect of gain/loss modulation in an evanescently coupled pair of microdisk optical resonators fabricated from solution-processed colloidal quantum dots. The emission spectra of these structures are sensitive to small imperfections, which cause frequency-splitting of the whispering gallery modes. Despite this inherent disorder, we found that when spatially modulating the optical pump to vary the gain differential between the coupled microdisks, the coupling drives the split parasitic intra-cavity modes into coalescence at an exceptional point of the resulting three-mode system. This unusual behavior is rationalized via a Hamiltonian that incorporates the intra-cavity coupling as well as the anisotropic inter-cavity coupling between modes in the microdisk pair.

10.
ACS Appl Mater Interfaces ; 10(43): 37267-37276, 2018 Oct 31.
Article in English | MEDLINE | ID: mdl-30338971

ABSTRACT

We report a simple, robust, and inexpensive strategy to enable all-inorganic CsPbX3 perovskite nanocrystals (NCs) with a set of markedly improved stabilities, that is, water stability, compositional stability, phase stability, and phase segregation stability via impregnating them in solid organic salt matrices (i.e., metal stearate; MSt). In addition to acting as matrices, MSt also functions as the ligand bound to the surface of CsPbX3 NCs, thereby eliminating the potential damage of NCs commonly encountered during purification as in copious past work. Quite intriguingly, the resulting CsPbX3-MSt nanocomposites display an outstanding suite of stabilities. First, they retain high emission in the presence of water because of the insolubility of MSt in water, signifying their excellent water stability. Second, anion exchange between CsPbBr3-MSt and CsPbI3-MSt nanocomposites is greatly suppressed. This can be ascribed to the efficient coating of MSt, thus effectively isolating the contact between CsPbBr3 and CsPbI3 NCs, reflecting notable compositional stability. Third, remarkably, after being impregnated by MSt, the resulting CsPbI3-MSt nanocomposites sustain the cubic phase of CsPbI3 and high emission, manifesting the strikingly improved phase stability. Finally, phase segregation of CsPbBr1.5I1.5 NCs is arrested via the MSt encapsulation (i.e., no formation of the respective CsPbBr3 and CsPbI3), thus rendering pure and stable photoluminescence (i.e., demonstration of phase segregation stability). Notably, when assembled into typical white light-emitting diode architecture, CsPbBr1.5I1.5-MSt nanocomposites exhibit appealing performance, including a high color rendering index ( Ra) and a low color temperature ( Tc). As such, the judicious encapsulation of perovskite NCs into organic salts represents a facile and robust strategy for creating high-quality solid-state luminophores for use in optoelectronic devices.

11.
ACS Appl Mater Interfaces ; 10(30): 25561-25569, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-30028583

ABSTRACT

This article reports for the time-resolved photophysical studies of spirally configured ( cis-stilbene) trimers and their spin-coated organic light-emitting diode (OLED) device performances. Transient absorption profiles of spirally configured, ter-( cis-stilbene) were studied by pulse radiolysis. The emission profiles after charge recombination of their incipient radical ions in benzene provides insights into the emission mechanism and efficiency in OLED devices. Blue-, sky blue-, and green-emitting OLED devices for a maximum external quantum efficiency are 4.32%, 4.70%, and 2.77%, respectively, by solution process.

12.
ACS Appl Mater Interfaces ; 9(20): 17435-17448, 2017 May 24.
Article in English | MEDLINE | ID: mdl-28441503

ABSTRACT

This work demonstrates a facile and versatile method for generating low scattering cross-linked quantum dot (QD)-polymer composite films and patterned highly emissive structures with ultrahigh QD loading, minimal phase separation, and tunable mechanical properties. Uniform QD-polymer films are fabricated using thiol-ene chemistry, in which cross-linked polymer networks are rapidly produced in ambient conditions via fast UV polymerization in bulk to suppress QD aggregation. UV-controlled thiol-ene chemistry limits phase separation through producing highly QD loaded cross-linked composites with loadings above majority of those reported in the literature (<1%) and approaching 30%. As the QD loading is increased, the thiol and ene conversion decreases, resulting in nanocomposites with widely variable and tailorable mechanical properties as a function of UV irradiation time with an elastic modulus decreasing to 1 GPa being characteristic of reinforced elastomeric materials, in contrast to usually observed stiff and brittle materials under these loading conditions. Furthermore, we demonstrate that the thiol-ene chemistry is compatible with soft-imprint lithography, making it possible to pattern highly loaded QD films while preserving the optical properties essential for high gain and low optical loss devices. The versatility of thiol-ene chemistry to produce high-dense QD-polymer films potentially makes it an important technique for polymer-based elastomeric optical metamaterials, where efficient light propagation is critical, like peculiar waveguides, sensors, and optical gain films.

13.
Angew Chem Int Ed Engl ; 55(16): 5071-5, 2016 Apr 11.
Article in English | MEDLINE | ID: mdl-26990250

ABSTRACT

The key to utilizing quantum dots (QDs) as lasing media is to effectively reduce non-radiative processes, such as Auger recombination and surface trapping. A robust strategy to craft a set of CdSe/Cd(1-x)Zn(x)Se(1-y)S(y)/ZnS core/graded shell-shell QDs with suppressed re-absorption, reduced Auger recombination rate, and tunable Stokes shift is presented. In sharp contrast to conventional CdSe/ZnS QDs, which have a large energy level mismatch between CdSe and ZnS and thus show strong re-absorption and a constrained Stokes shift, the as-synthesized CdSe/Cd(1-x)Zn(x)Se(1-y)S(y)/ZnS QDs exhibited the suppressed re-absorption of CdSe core and tunable Stokes shift as a direct consequence of the delocalization of the electron wavefunction over the entire QD. Such Stokes shift-engineered QDs with suppressed re-absorption may represent an important class of building blocks for use in lasers, light emitting diodes, solar concentrators, and parity-time symmetry materials and devices.

14.
ACS Nano ; 9(2): 1379-87, 2015 Feb 24.
Article in English | MEDLINE | ID: mdl-25603043

ABSTRACT

Low-temperature atomic layer deposition of conformal ZnO on a self-assembled block polymer lithographic template comprising well-ordered, vertically aligned cylindrical pores within a poly(styrene) (PS) matrix was used to produce nanocrucible templates with pore diameters tunable via ZnO thickness. Starting from a PS template with a hexagonal array of 30 nm diameter pores on a 45 nm pitch, the ZnO thickness was progressively increased to narrow the pore diameter to as low as 14 nm. Upon removal of the PS by heat treatment in air at 500 °C to form an array of size-tunable ZnO nanocrucibles, permalloy (Ni80Fe20) was evaporated at normal incidence, filling the pores and creating an overlayer. Argon ion beam milling was then used to etch back the overlayer (a Damascene-type process), leaving a well-ordered array of isolated ZnO nanocrucibles filled with permalloy nanodots. Microscopy and temperature-dependent magnetometry verified the diameter reduction with increasing ZnO thickness. The largest diameter (30 nm) dots exhibit a ferromagnetic multidomain/vortex state at 300 K, with relatively weakly temperature-dependent coercivity. Reducing the diameter leads to a crossover to a single-domain state and eventually superparamagnetism at sufficiently high temperature, in quantitative agreement with expectations. We argue that this approach could render this form of block polymer lithography compatible with high-temperature processing (as required for technologically important high perpendicular anisotropy ordered alloys, for instance), in addition to enabling separation-dependent studies to probe interdot magnetostatic interactions.

15.
ACS Appl Mater Interfaces ; 6(16): 13770-81, 2014 Aug 27.
Article in English | MEDLINE | ID: mdl-25029410

ABSTRACT

Detailed experiments designed to optimize and understand the solvent vapor annealing of cylinder-forming poly(styrene)-block-poly(lactide) thin films for nanolithographic applications are reported. By combining climate-controlled solvent vapor annealing (including in situ probes of solvent concentration) with comparative small-angle X-ray scattering studies of solvent-swollen bulk polymers of identical composition, it is concluded that a narrow window of optimal solvent concentration occurs just on the ordered side of the order-disorder transition. In this window, the lateral correlation length of the hexagonally close-packed ordering, the defect density, and the cylinder orientation are simultaneously optimized, resulting in single-crystal-like ordering over 10 µm scales. The influences of polymer synthesis method, composition, molar mass, solvent vapor pressure, evaporation rate, and film thickness have all been assessed, confirming the generality of this behavior. Analogies to thermal annealing of elemental solids, in combination with an understanding of the effects of process parameters on annealing conditions, enable qualitative understanding of many of the key results and underscore the likely generality of the main conclusions. Pattern transfer via a Damascene-type approach verified the applicability for high-fidelity nanolithography, yielding large-area metal nanodot arrays with center-to-center spacing of 38 nm (diameter 19 nm). Finally, the predictive power of our findings was demonstrated by using small-angle X-ray scattering to predict optimal solvent annealing conditions for poly(styrene)-block-poly(lactide) films of low molar mass (18 kg mol(-1)). High-quality templates with cylinder center-to-center spacing of only 18 nm (diameter of 10 nm) were obtained. These comprehensive results have clear and important implications for optimization of pattern transfer templates and significantly advance the understanding of self-assembly in block copolymer thin films.

16.
Macromol Rapid Commun ; 33(2): 107-13, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22134984

ABSTRACT

The synthesis and electrochemical performance of three-dimensionally ordered macroporous (3DOM) nitroxide polymer brush electrodes for organic radical batteries are reported. The 3DOM electrodes are synthesized via polystyrene colloidal crystal templating with electropolymerization of polypyrrole, modification of surface initiator, and surface-initiated atom transfer radical polymerization. The discharge capacity of the 3DOM electrodes is proportional to the thickness of the inverse opal. The discharge capacity of the 3DOM electrode at a discharge rate of 5 C is 40 times higher than that of the planar electrode; its cycle-life performance exhibits 96.1% retention after 250 cycles.


Subject(s)
Polymers/chemistry , Polystyrenes/chemistry , Pyrroles/chemistry , Electrochemistry/methods , Electrodes , Porosity
17.
Chem Commun (Camb) ; 47(4): 1249-51, 2011 Jan 28.
Article in English | MEDLINE | ID: mdl-21103524

ABSTRACT

Nitroxide polymer brushes were covalently patterned on flexible conducting substrates via surface-initiated atom transfer radical polymerization and microcontact printing. As a cathode of organic radical batteries, the nitroxide polymer brushes prevent the nitroxide polymer from dissolving into electrolyte solvents, which improves the cycle-life performance of batteries.

18.
J Gen Virol ; 86(Pt 4): 899-905, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15784884

ABSTRACT

The aim of this study was to investigate Epstein-Barr virus (EBV)-related virus infection in pet dogs. The presence of antibodies to EBV antigens and EBV-related DNA was determined by Western blot analysis and PCR, respectively. Among 36 pet dogs examined for serum antibodies, 32 (88.9%) were positive for EBV-specific thymidine kinase, 15 (41.7%) for EBV-encoded DNA-binding protein and 10 (27.8%) for EBV-specific DNA polymerase. A BamHI W fragment sequence encoding part of the EBV nuclear antigen leader protein was detected by PCR in corresponding leukocyte DNA samples. Among 21 dogs tested, 15 (71.4%) were positive for the BamHI W fragment sequence. The specificity of the amplified DNA fragments was confirmed by DNA sequencing. Within the amplified region of the BamHI W fragment (241 bp), DNA sequences detected in 10 dogs had 99.2% (two nucleotide variations), 99.6% (one nucleotide variation) or 100% identity to that of EBV. Furthermore, an EBV-encoded RNA signal was detected by in situ hybridization in dog lymphocytes, as well as in bone-marrow sections, indicating a latent infection with EBV or an EBV-like virus. In conclusion, although the sample size was small, these results showed that a widespread EBV-related gammaherpesvirus could be detected in the peripheral blood and bone marrow of pet dogs. Although no evident zoonotic transmission was detected, further studies are imperative for disclosing the biological significance of this canine EBV-like virus, which may correlate with human disorders.


Subject(s)
DNA, Viral/chemistry , Dog Diseases/virology , Epstein-Barr Virus Infections/veterinary , Epstein-Barr Virus Nuclear Antigens/genetics , Herpesvirus 4, Human/genetics , RNA, Viral/genetics , Amino Acid Sequence , Animals , Antibodies, Viral/blood , Base Sequence , DNA, Viral/immunology , Deoxyribonuclease BamHI , Dog Diseases/epidemiology , Dog Diseases/immunology , Dogs , Epstein-Barr Virus Infections/epidemiology , Epstein-Barr Virus Infections/immunology , Epstein-Barr Virus Infections/virology , Epstein-Barr Virus Nuclear Antigens/immunology , Female , Herpesvirus 4, Human/isolation & purification , In Situ Hybridization , Leukocytes/chemistry , Male , Molecular Sequence Data , Polymerase Chain Reaction , RNA, Viral/immunology , Sequence Analysis, DNA
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