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1.
Anim Biotechnol ; 35(1): 2390936, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39150792

RESUMEN

This experiment was conducted to investigate the effect of stimbiotic (STB) in broilers with necrotic enteritis (NE). A total of 180 one-day-old Arbor Acres (initial body weight of 34.81 ± 1.04 g) were used in this experiment for 32 days. All broilers were randomly allocated into six treatments, and each experimental group had 10 replicate cages with three broilers per cage. The experiment was conducted in a 2 × 3 factorial design consisting of two levels of challenge (challenge and non-challenge) and three levels of STB (0, 0.05, and 0.1%). The NE challenge significantly decreased (P < 0.05) growth performance, heterophil levels in blood, and intestinal lesion scores compared to the non-challenge group. Supplementation of 0.05% STB significantly decreased (P < 0.05) feed conversion ratio and the number of oocysts per gram of feces compared to the supplementation of 0 and 0.1% STB. At the genus level, the supplementation of 0.05% STB significantly decreased (P < 0.05) the abundance of Enterobacterales compared to the other groups on d 32. In conclusion, supplementation with 0.05% STB in a diet could positively regulate the fecal microflora and alleviate the decline in growth performance and nutrient digestibility caused by NE.


Asunto(s)
Alimentación Animal , Pollos , Suplementos Dietéticos , Enteritis , Microbioma Gastrointestinal , Enfermedades de las Aves de Corral , Animales , Pollos/crecimiento & desarrollo , Enteritis/veterinaria , Enfermedades de las Aves de Corral/parasitología , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Alimentación Animal/análisis , Digestión/fisiología , Digestión/efectos de los fármacos , Oocistos , Dieta/veterinaria , Necrosis , Probióticos/farmacología , Probióticos/administración & dosificación , Nutrientes , Heces/microbiología , Heces/parasitología , Masculino
2.
Knee Surg Sports Traumatol Arthrosc ; 32(2): 445-453, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38270291

RESUMEN

PURPOSE: This study aimed to compare long-term clinical and radiographic outcomes and survival rates between navigation-assisted (NAV) total knee arthroplasty (TKA) and conventional (CON) TKA using a mobile-bearing insert. METHODS: From May 2008 to December 2009, 45 and 63 mobile-bearing TKA patients were enroled in the CON- and NAV-TKA groups with 146.8 months follow-up, respectively. Clinical outcomes (Western Ontario and McMaster University Osteoarthritis Index and Knee Society Scores), radiographic outcomes (hip-knee-ankle [HKA], lateral distal femoral, medial proximal tibial, γ, and δ angles), and survivorship were compared between both groups. RESULTS: The number of HKA angle outliers (more than 3 degrees or less than -3 degree) was significantly lower in the NAV-TKA group (24.4% vs. 9.5%, p = 0.036) than in the CON-TKA group. However, long-term clinical outcomes were similar between both groups. The cumulative survival rate (best-case scenario) was 98.3% in the CON-TKA group and 97.5% in the NAV-TKA group, with no significant difference between the groups (p = 0.883). CONCLUSION: Long-term clinical outcomes and survival rates were similar between the two groups despite fewer outliers of postoperative lower-limb alignment in the NAV-TKA group. Excellent survival rates were observed in both groups using mobile-bearing inserts. LEVEL OF EVIDENCE: Level IV, case series.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Cirugía Asistida por Computador , Humanos , Tasa de Supervivencia , Estudios de Seguimiento , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Estudios Retrospectivos
3.
Medicina (Kaunas) ; 60(5)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38792971

RESUMEN

Background and Objectives: Patella baja is a common complication after operative treatment for patellar fracture. This study aimed to investigate (1) the serial changes in patellar height and (2) the potential predictive factors for patellar height changes after tension band wiring (TBW) for patellar fractures. Materials and Methods: Forty-one patients who underwent TBW for patellar fracture between March 2019 and September 2022 were enrolled. To identify serial changes in patellar height, modified Blackburne-Peel index (mBPI) was assessed at just after surgery, at 3 months, at 6 months, at 1 year and at the final follow-up. Multiple regression analysis was conducted to identify factors correlated with mBPI difference between the contralateral side (considered as preoperative status) and injured side. Results: The postoperative mBPI exhibited a decline over time (mean mBPI immediately post operation/3 months/6 months/1 year/final follow-up: 0.69/0.63/0.63/0.62/0.61) Specifically, mBPI showed a significant reduction immediately post operation to 3 months (p < 0.001), although comparisons at other time points did not reveal significant differences. A lower position of the fracture was associated with a decrease in patellar height after surgery. Conclusions: Patellar height was mainly decreased from immediately post operation to 3 months. A fracture in a lower position of associated with decreased patellar height after the TBW of the transverse patellar fracture.


Asunto(s)
Fracturas Óseas , Rótula , Humanos , Rótula/lesiones , Masculino , Femenino , Adulto , Fracturas Óseas/cirugía , Persona de Mediana Edad , Estudios Retrospectivos , Hilos Ortopédicos/efectos adversos , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/efectos adversos
4.
J Hand Surg Am ; 48(1): 85.e1-85.e10, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34839963

RESUMEN

PURPOSE: Local steroid injection is an effective treatment modality for carpal tunnel syndrome. This study aimed to investigate the success rate of ultrasonography-guided local steroid injection and determine the prognostic value of the cross-sectional area (CSA) of the median nerve for steroid injection. METHODS: We retrospectively evaluated 40 patients with carpal tunnel syndrome whose median nerve CSA was >15 mm2 (large-CSA group; n = 16) or ≤15 mm2 (small-CSA group; n = 24). The CSA was measured using ultrasonography, and all the patients were treated with ultrasonography-guided corticosteroid injection. Demographic characteristics, symptoms, initial QuickDASH score, Boston Carpal Tunnel Questionnaires, and results of the nerve conduction study were assessed at baseline. Treatment success was defined in this study as the absence of symptom recurrence within the entire follow-up period. RESULTS: The treatment success rate was 45% (n = 18) after an average follow-up of 16 months. Overall, 11 patients (28%) underwent carpal tunnel release on an average of 11 months after steroid injection. The large-CSA group showed a significantly worse grade of electrodiagnostic testing at baseline than did the small-CSA group; however, there was no significant difference in final Boston Carpal Tunnel Questionnaires symptom score (1.7 vs 1.8, respectively) and the rate of continued treatment success at the last follow-up (42% vs 50%, respectively). The proportions of patients who required carpal tunnel decompression were 29% and 25% in the small-CSA and large-CSA groups, respectively. CONCLUSIONS: Local steroid injection for carpal tunnel syndrome has an overall success rate of 45% after a mean follow-up of 16 months. Preinjection CSA was not associated with whether the steroid injection was considered successful. This indicates that increased median nerve CSA does not preclude the possibility of symptomatic relief after a local steroid injection. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Síndrome del Túnel Carpiano , Nervio Mediano , Humanos , Nervio Mediano/diagnóstico por imagen , Nervio Mediano/cirugía , Síndrome del Túnel Carpiano/diagnóstico por imagen , Síndrome del Túnel Carpiano/tratamiento farmacológico , Síndrome del Túnel Carpiano/cirugía , Pronóstico , Estudios Retrospectivos , Ultrasonografía , Esteroides/uso terapéutico
5.
Vet Med (Praha) ; 68(5): 191-199, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37982025

RESUMEN

This study aimed to use lactic acid bacteria isolated from piglet faeces to develop probiotics, allowing for the effective control of Escherichia coli and Salmonella. Lactic acid bacteria were isolated from the faeces of suckling piglets and identified by 16S rRNA sequencing, then examined for haemolysis; gelatinase activity; and resistance to acid, bile, and pancreatin. The antimicrobial activity of selected lactic acid bacteria isolates was examined for 8 E. coli and 7 Salmonella strains. One-hundred and sixty-four lactic acid bacteria isolates were identified from 118 piglet faecal samples, and 13 lactic acid bacteria isolates were selected from analyses of haemolysis; gelatinase activity; and resistance to acid, bile, and pancreatin. Of the selected 13 lactic acid bacteria isolates, Limosilactobacillus reuteri PF20-3 and PF30-3 strains had the highest antibacterial activity against E. coli and Salmonella.

6.
Medicina (Kaunas) ; 58(9)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36143888

RESUMEN

Background and Objectives: The tibial component alignment is an important issue for the longevity of total knee arthroplasty (TKA). The purpose of our study was to investigate the usefulness of proximal tibial references determined by pre-operative radiography and intraoperative C-arm-guided hip and ankle center marking for the extramedullary guided tibial cut in mild (<10°) and severe (≥10°) varus knee TKA. Materials and Methods: A total of 150 consecutive patients (220 cases) who underwent total knee arthroplasty who were recruited from July 2011 to April 2017 were reviewed retrospectively. Before surgery, the proximal tibial reference point and medio-lateral cut thickness difference were identified. Then, hip and ankle centers were checked using a C-arm intensifier intraoperatively. The hip−knee−ankle (HKA) alignment and medial proximal tibial angle (MPTA) were assessed pre-operatively and post-operatively. More than 3° varus or valgus of HKA alignment or tibial component angle was defined as an outlier. Results: Mean follow-up duration was 26.9 months. Among 220 cases, 111 cases are classified as mild varus group and 109 cases are classified as severe varus group. The HKA alignment is significantly improved (p < 0.001). The average tibial component angle after surgery is 90.1°. A total of 21 cases (9.5%) and 3 cases (1.4%) are classified as outliers of HKA alignment and MPTA, respectively. Among MPTA outliers, one case is in the mild varus group and two cases are in the in severe varus group (p = 0.62). Conclusion: Measurement of proximal tibial radiographic references and checking the C-arm-guided intraoperative hip and ankle center could be helpful to obtain the favorable coronal position of the tibial component in the extramedullary guided tibial cut.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/cirugía , Estudios Retrospectivos , Tibia/diagnóstico por imagen , Tibia/cirugía
7.
Medicina (Kaunas) ; 58(12)2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36556989

RESUMEN

Background and Objectives: A reduction forced toward the posterior side during graft fixation may help to lessen anterior tibial translation after ACL reconstruction. The purpose was to compare the clinical and radiological outcomes of graft fixation when a posterior draw was used and when it was not used during anterior cruciate ligament (ACL) reconstruction surgery. Materials and Methods: Of 110 patients who had undergone primary arthroscopic ACL reconstruction between January 2017 and August 2020, in all, 76 patients had been operated on without a posterior draw (non-draw group), and 34 patients had received surgery with a posterior draw (draw group). The results of the Lachman test and the pivot-shift test, the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) indexes, the Lysholm scores, the International Knee Documentation Committee (IKDC) subjective scores, and side-to-side difference (STSD) on stress radiography were compared between the two groups. Results: The postoperative WOMAC indexes, Lysholm scores, and IKDC subjective scores were similar across both groups. Postoperative STSD (2.4 ± 2.2 for the non-draw group vs. 2.0 ± 2.2 for the draw group; p = 0.319) and change in STSD (3.5 ± 3.5 for preoperative STSD vs. 4.3 ± 4.4 for postoperative STSD; p = 0.295) were not superior in the draw group. Conclusions: The take-home message is that graft fixation with a posterior draw during ACL reconstruction did not result in significantly better postoperative stability. The postoperative clinical outcomes were similar between both groups.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Humanos , Resultado del Tratamiento , Lesiones del Ligamento Cruzado Anterior/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Tibia/cirugía
8.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923716

RESUMEN

In this study, we developed a new type of wireless transmission system for use in partially implantable hearing aids. This system was designed for miniaturization and low distortion, and features direct digital modulation. The sigma-delta output, which has a high SNR due to oversampling and noise shaping technology, is used as the data signal and is transmitted using a wireless transmission system to the implant unit through OOK without restoration as an audio signal, thus eliminating the need for additional circuits (i.e., LPF and a reference voltage supply circuit) and improving the ease of implantation and reliability of the circuit. We selected a carrier frequency of 27 MHz after analysis of carrier attenuation by human tissue, and designed the communication coil with reference to both the geometry and required communication distance. Circuit design and simulation for wireless transmission were performed using Multisim 13.0. The system was fabricated based on the circuit design; the size of the device board was 13 mm × 13 mm, the size of the implanted part was 9 mm × 9 mm, the diameter of the transmitting/receiving coil was 26 mm, and the thicknesses of these coils were 0.5 and 0.3 mm, respectively. The difference (error) between the detected and simulation waveforms was about 5%, and was thought to be due to the tolerances of the fabricated communication coil and elements (resistors, capacitors, etc.) used in the circuit configuration of the system. The number of windings was reduced more than 9-fold compared to the communication coil described by Taghavi et al. The measured THD was <1% in the frequency band from 100 Hz to 10 kHz, thus easily meeting the standard specification for hearing aids.


Asunto(s)
Audífonos , Diseño de Equipo , Humanos , Miniaturización , Prótesis e Implantes , Reproducibilidad de los Resultados , Tecnología Inalámbrica
9.
Molecules ; 26(4)2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33557189

RESUMEN

The physical and mechanical properties of nitrile-butadiene rubber (NBR) composites with N-cetylpyridinium bromide-carbon black (CPB-CB) were investigated. Addition of 5 parts per hundred rubber (phr) of CPB-CB into NBR improved the tensile strength by 124%, vulcanization rate by 41%, shore hardness by 15%, and decreased the volumetric wear by 7% compared to those of the base rubber-CB composite.


Asunto(s)
Butadienos/química , Cetilpiridinio/química , Fenómenos Mecánicos , Nitrilos/química , Fenómenos Físicos , Goma/química , Hollín/química
10.
Sensors (Basel) ; 19(5)2019 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-30841613

RESUMEN

To develop totally implantable middle ear and cochlear implants, a miniature microphone that is surgically easy to implant and has a high sensitivity in a sufficient range of audio frequencies is needed. Of the various implantable acoustic sensors under development, only micro electro-mechanical system-type acoustic sensors, which attach to the umbo of the tympanic membrane, meet these requirements. We describe a new vibro-acoustic hybrid implantable microphone (VAHIM) that combines acceleration and sound pressure sensors. Each sensor can collect the vibration of the umbo and sound pressure of the middle ear cavity. The fabricated sensor was implanted into a human temporal bone and the noise level and sensitivity were measured. From the experimental results, it is shown that the proposed method is able to provide a wider-frequency band than conventional implantable acoustic sensors.


Asunto(s)
Técnicas Biosensibles , Implantes Cocleares , Audífonos , Humanos , Diseño de Prótesis
11.
Molecules ; 24(2)2019 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-30634465

RESUMEN

Mixtures of layered silicates (vermiculite and kaolinite) and carbon fibers were investigated as filler materials for polytetrafluoroethylene. The supramolecular structure and the tribological and mechanical properties of the resulting polymer composite materials were evaluated. The yield strength and compressive strength of the polymer increased by 55% and 60%, respectively, when a mixed filler was used, which was attributed to supramolecular reinforcement of the composites. In addition, the wear resistance increased by 850 times when using vermiculite/kaolinite fillers, which was due to protection of the surface by the formation of hard tribofilms.


Asunto(s)
Fibra de Carbono/química , Politetrafluoroetileno/química , Silicatos/química , Silicatos de Aluminio/química , Fuerza Compresiva , Dureza , Caolín/química , Ensayo de Materiales
12.
Sensors (Basel) ; 18(6)2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29795018

RESUMEN

The design and implementation of a novel piezoelectric-based actuator for an implantable middle-ear hearing aid is described in this paper. The proposed actuator has excellent low-frequency output characteristics, and can generate high output in a specific frequency band by adjusting the mechanical resonance. The actuator consists of a piezoelectric element, a miniature bellows, a cantilever membrane, a metal ring support, a ceramic tip, and titanium housing. The optimal structure of the cantilever-membrane design, which determines the frequency characteristics of the piezoelectric actuator, was derived through finite element analysis. Based on the results, the piezoelectric actuator was implemented, and its performance was verified through a cadaveric experiment. It was confirmed that the proposed actuator provides better performance than currently used actuators, in terms of frequency characteristics.


Asunto(s)
Audífonos , Prótesis Osicular , Cadáver , Análisis de Elementos Finitos , Humanos , Hueso Temporal/fisiopatología , Titanio/química , Titanio/uso terapéutico , Vibración
13.
Molecules ; 23(9)2018 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-30150557

RESUMEN

Sealing rubbers employed in cold climates such as the Siberian Arctic must be able to withstand temperatures as low as -50 °C while still exhibiting specific relaxation, strength, tribological characteristics, and a resistance to aggressive media. Previous investigations of propylene oxide rubber (SKPO, Tg = -73 °C) modified with polytetrafluoroethylene (PTFE) have revealed that, while the rubber composite materials exhibit double the wear resistance compared to unmodified polypropylene oxide rubber, they have poor frost resistance. In the present study, we developed materials based on SKPO and ultrafine PTFE (UPTFE), which can be characterized by its smaller particle size, low molecular weight, high tribo-technical characteristics, and resistance to aggressive media. The properties of the rubber composites were evaluated using the standard methods. The structures of the materials were investigated by electron microscopy and XRD analysis. It was shown that the materials have excellent wear resistance, resistance to aggressive media, compression set, and low-temperature resistance. The addition of UPTFE is preferable to the addition of PTFE because the desired positive effects can be attained with only 0.5⁻1 parts per hundred parts of rubber (phr) UPTFE while 20 phr PTFE would be necessary.


Asunto(s)
Compuestos Epoxi/química , Compuestos Epoxi/aislamiento & purificación , Goma/química , Ensayo de Materiales , Fenómenos Mecánicos , Difracción de Rayos X
14.
J Anim Physiol Anim Nutr (Berl) ; 102(5): 1257-1265, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29968943

RESUMEN

Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28-day-old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 µl carvacrol essential oils at 18:00 hr every day during the 2-week experimental period. As a result of which, the gene expression of the occludin, claudin-1, claudin-5, ZO-1 and ZO-2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 µl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 µl was more effective than that of 200 µl.


Asunto(s)
Pollos , Microbioma Gastrointestinal/efectos de los fármacos , Intestinos/fisiología , Monoterpenos/farmacología , Aceites Volátiles/farmacología , Administración Oral , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Pollos/microbiología , Pollos/fisiología , Cimenos , Dieta , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Microbioma Gastrointestinal/fisiología , Intestinos/efectos de los fármacos
15.
Molecules ; 22(12)2017 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-29206140

RESUMEN

In this study, the reinforcement of ultrahigh-molecular-weight polyethylene (UHMWPE) with biotite was investigated. The biotite filler was mechanically activated with different dry surfactants to improve its compatibility with UHMWPE and decrease agglomeration among biotite particles. Alkyldimethylbenzylammonium chloride (ADBAC) and cetyltrimethylammonium bromide (CTAB) were selected as cationic surfactants. The tensile strength of composites containing 1 wt % of CTAB-treated biotite was increased by 30% relative to those with untreated biotite, but was unchanged with ADBAC treatment of the same biotite content. The stereochemistry of the surfactant may be critical to the composite structure and mechanical properties of the material. The stereochemistry of CTAB was preferable to that of ADBAC in enhancing mechanical properties because the stereochemistry of ADBAC impedes favorable interactions with the biotite surface during mechanical activation.


Asunto(s)
Silicatos de Aluminio/química , Compuestos de Benzalconio/química , Compuestos de Cetrimonio/química , Compuestos Ferrosos/química , Polietilenos/química , Tensoactivos/química , Cetrimonio , Frío , Materiales de Construcción , Humanos , Ensayo de Materiales , Resistencia a la Tracción
16.
Opt Express ; 23(9): 11783-9, 2015 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-25969269

RESUMEN

We theoretically demonstrate spontaneous PT-symmetry breaking behavior of surface-plasmon polaritons (SPP) in coupled double-slab (DS) waveguides. By virtue of a flat-top field at critical wavelength, the imaginary index of a DS-SPP mode can be controlled via changing the core thickness, while the real index is kept constant. Therefore, a waveguide coupler that consists of a pair of DS-SPP waveguides with different core thicknesses can represent a passive PT-symmetric system, which always maintains symmetry under a real potential. This set-up also represents a good opportunity to investigate the underlying physics of PT-symmetry breaking in non-Hermitian Hamiltonian systems.

17.
Opt Express ; 23(13): 17443-9, 2015 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-26191753

RESUMEN

Exploiting moiré interference, we make a new type of reconfigurable metamaterials and study their transmission tunability for incident electromagnetic waves. The moiré pattern is formed by overlapping two transparent layers, each of which has a periodic metallic pattern, and the cluster size of the resulting moiré pattern can be varied by changing the relative superposition angle of the two layers. In our reconfigurable metamaterials, both the size and structural shape of the unit cell can be varied simultaneously through moiré interference. We show that the transmission of electromagnetic waves can be controlled from 90% to 10% at 11 GHz by experiments and numerical simulation. The reconfigurable metamaterial proposed here can be applied in bandpass filters and tunable modulation devices.

18.
Sensors (Basel) ; 15(9): 22798-810, 2015 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-26371007

RESUMEN

Fully implantable hearing devices (FIHDs) have been developed as a new technology to overcome the disadvantages of conventional acoustic hearing aids. The implantable microphones currently used in FIHDs, however, have difficulty achieving high sensitivity to environmental sounds, low sensitivity to body noise, and ease of implantation. In general, implantable microphones may be placed under the skin in the temporal bone region of the skull. In this situation, body noise picked up during mastication and touching can be significant, and the layer of skin and hair can both attenuate and distort sounds. The new approach presently proposed is a microphone implanted at the tympanic membrane. This method increases the microphone's sensitivity by utilizing the pinna's directionally dependent sound collection capabilities and the natural resonances of the ear canal. The sensitivity and insertion loss of this microphone were measured in human cadaveric specimens in the 0.1 to 16 kHz frequency range. In addition, the maximum stable gain due to feedback between the trans-tympanic microphone and a round-window-drive transducer, was measured. The results confirmed in situ high-performance capabilities of the proposed trans-tympanic microphone.


Asunto(s)
Implantes Cocleares , Audífonos , Membrana Timpánica/cirugía , Humanos , Diseño de Prótesis , Hueso Temporal/cirugía
19.
Animals (Basel) ; 14(11)2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38891738

RESUMEN

In Experiment 1, a total of eighteen crossbred ([Landrace × Yorkshire] × Duroc) barrows with an initial body weight of 6.74 ± 0.68 kg were randomly divided into three dietary treatments (one pig per cage and six replicates per treatment) and housed in metabolic cages that were equipped with a feeder and slatted floor to collect urine and feces. In Experiment 2, a total of 96 crossbred ([Landrace × Yorkshire] × Duroc) barrows with an initial body weight of 8.25 ± 0.42 kg were used in the 6-week trial. The pigs were randomly divided into three dietary treatments (three pigs per pen and eight replicates per treatment). In Experiment 1, nutrient composition of defatted black soldier fly larvae meal (BLM) was superior to that of hydrolyzed BLM but lower than that of fish meal (FM). Also, defatted BLM and FM had better apparent total track digestibility (ATTD) of crude protein (CP) and better nitrogen retention (p < 0.05) than hydrolyzed BLM, but there was no significant difference (p > 0.05) between defatted BLM and FM. In Experiment 2, defatted BLM improved (p < 0.05) average daily gain (ADG), feed conversion ratio (FCR), and feed cost per kg gain (FCG) compared with FM. Defatted BLM could replace soybean meal and fish meal as an alternative protein source for weaning pigs.

20.
Animals (Basel) ; 14(7)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38612315

RESUMEN

As high temperature and relative humidity (RH) are the main environmental factors causing heat stress, the temperature-humidity index (THI) serves as an indicator of heat stress in livestock animals. This study aimed to determine the effects of heat stress on the laying performance, physiological responses, egg quality, and blood profile of laying hens by subjecting them to environmental conditions with varying THI levels (68-85) for 28 days. The indicators of laying performance, such as feed intake (-30%) and egg production rate (-11%), significantly decreased in the hens exposed to severe heat stress (33 °C, 66% RH) compared to those exposed to thermoneutral conditions (21 °C, 68% RH). Moreover, severe heat stress reduced the egg yolk color, eggshell thickness and strength, and Haugh units of the eggs produced by the laying hens. Furthermore, a significant increase in serum K+ and a decrease in Na+ levels were observed in the hens subjected to severe heat stress compared with those under thermoneutral conditions. Our results indicate that heat stress alters the physiological responses and metabolism of laying hens, resulting in a lower egg quality and production rate.

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