The treated clubfoot children are often evaluated clinically during follow-up. However, patient reported outcomes (PROM) are seldom analysed for these children. We investigated 87 idiopathic clubfoot ...children (140 feet) treated by the Ponseti method and followed minimum 5 years to study their clinical outcomes and PROM.
This was a cross-sectional study, based on evaluating treated clubfoot children clinically (Pirani score) and PROM (Oxford Ankle and Foot Questionnaire – Parent Version) and comparing them with the age-matched healthy controls (n = 60). The questionnaire has four main domains related to the child's physical, school and play, emotional and footwear profile. The children having persistent deformity (residual/relapse) were specifically studied for their PROM scores.
The mean child age at initial treatment was 2.3 months and the mean follow-up duration was 6.9 years. The PROM score of clubfoot children was statistically lower than the healthy controls (p < 0.001). Of the individual domains, the physical domain was the most affected. On calculating the Pirani scores, 10 out of 140 feet (7 %) had some form of persistent deformity. The children with persistent deformity had lower Oxford scores than healthy children or those with corrected feet. The physical domain followed by the emotional domain scored low when persistent deformity was present.
Most children (98 %) had a plantigrade foot following Ponseti treatment at follow-up. However, PROM score of the clubfoot children did not correspond to the clinical outcome. Persistent deformity, even minor, was a cause of parental concern and resulted in a low PROM score.
This article presents a titanium-nitride composite (TiN-C)-based complementary metal-oxide- semiconductor microelectromechanical system (CMOS-MEMS) Pirani gauge integrated into the back-end-of-line ...(BEOL) layers. A microbeam architecture is utilized as the sensing element consisting of a stack of TiN and SiO<inline-formula> <tex-math notation="LaTeX">_{\text{2}}</tex-math> </inline-formula>. The structure utilizes the sandwiched (TiN/AlCu/TiN) metal line configuration to craft the suspended sensing element having a nanogap from the substrate. TiN serves as the heating element in the sensing element, while SiO<inline-formula> <tex-math notation="LaTeX">_{\text{2}}</tex-math> </inline-formula> provides mechanical support to the structure. Gauges with lengths varying from 60 to 90 <inline-formula> <tex-math notation="LaTeX">\mu</tex-math> </inline-formula>m are proposed, while the width is kept the same, i.e., 4 <inline-formula> <tex-math notation="LaTeX">\mu</tex-math> </inline-formula>m. Since the BEOL-integrated MEMS devices are prone to suffer from residual stress, an optical profilometer analysis is performed to quantify the effective value of the suspended gap. Furthermore, temperature profiles of the proposed designs are evaluated using COMSOL Multiphysics. Finally, the fabricated gauges are tested for pressure-dependent response from 1 to 10<inline-formula> <tex-math notation="LaTeX">^{\text{6}}</tex-math> </inline-formula> Pa and a performance comparison is established. In the monolithic CMOS-MEMS implementation, a lower detection limit of 15.5, 12.3, 10.3, and 8.3 Pa is obtained for different gauge lengths, while the upper detection range is the same, i.e., 10<inline-formula> <tex-math notation="LaTeX">^{\text{6}}</tex-math> </inline-formula> Pa.
In this paper, we present a surface micromachined Pirani vacuum gauge integrated with a stacked temperature sensor using CMOS-MEMS technology. The proposed Pirani gauge features a <inline-formula> ...<tex-math notation="LaTeX">2.23~\mu \text{m} </tex-math></inline-formula> thick suspended microheater, which is positioned between two designed heat sinks. The upper and lower gap spacing between the heat sink and the microheater is <inline-formula> <tex-math notation="LaTeX">0.53~\mu \text{m} </tex-math></inline-formula>, which is made by the surface etching of two metal films. Additionally, a temperature sensor based on a poly-Si resistor is directly integrated into the lower heat sink. The temperature sensor shows a sensitivity of 45 ohm/°C over a linear range of 10~60 °C, while its measurement error is less than 0.11 °C in the worst case. The Pirani gauge achieves a high sensitivity of 0.96 V/Dec under fine vacuum conditions, and its heating power is less than 8.3 mW in the vacuum range of 0.8~14000 Pa. Moreover, the measured output of the Pirani gauge closely matches the proposed semi-empirical model, while the noise measurements indicate that the sensor has a resolution as low as <inline-formula> <tex-math notation="LaTeX">6.4\times 10 ^{\mathbf {-3}} </tex-math></inline-formula> Pa in very fine vacuum conditions. This integrated Pirani gauge and temperature sensor system, in combination with its high performance, makes it a promising sensing node for vacuum and temperature monitoring in semiconductor equipment. 2023-0184
The aim of this study was to track the correction of individual components of Pirani scoring system (PSS) over the manipulation and tenotomy phase of Ponseti casting method in idiopathic clubfoot. ...Additionally, non-zero PSS scores were analysed to find out the residual deformities.
The included feet were assessed initially according to the six component PSS. The individual scores of each component of midfoot and hindfoot were scored at each visit till the final follow up. The final scoring was done before the start of the bracing phase of the feet (with or without tenotomy).
Evaluation was performed for 42 feet in 28 infants (14 bilateral) with mean age of 42.5 ± 39.2 days (range, 15-150 days). All the six components of PSS showed a significant change from the first cast till the pre tenotomy cast. Post tenotomy, there was a significant change in the scores of posterior crease (0.4 ± 0.2 to 0.1 ± 0.1, p < 0.001) and rigid equinus (0.8 ± 0.3 to 0.1 ± 0.2, p < 0.001). 66.7 % (28/42) of the feet had an abnormal empty heel sign of either 0.5 22/42 (52.3 %) or 1 6/42 (14.4 %) at initiation of bracing.
The individual components of Pirani scoring system changed to a variable extent as the treatment progressed. Curvature lateral border and talar head reached normalcy prior to tenotomy. Posterior crease and rigid equinus showed a significant reduction after tenotomy. The non-zero empty heel component may require careful interpretation both post treatment and during follow ups.
This work reports a thin-film encapsulated package with porous alumina as the capping layer and titanium as a pore-sealing getter. The titanium-gold film seals the thin film package and acts as the ...getter. Since the getter is not exposed to the elements, fouling of the getter is prevented. EDX measurements confirm that the getter material did not penetrate the package through the nanopores. The process is a low thermal budget process, with the getter activation (300 <inline-formula> <tex-math notation="LaTeX">^{\circ}</tex-math> </inline-formula>C for 1 hour) being the only step where the temperature is raised. A Silicon Pirani gauge was used to monitor the pressure changes inside the sealed cavity. After the getter activation, a decrease in the pressure from 50 <inline-formula> <tex-math notation="LaTeX">\mu</tex-math> </inline-formula>Torr to 3.9 <inline-formula> <tex-math notation="LaTeX">\mu</tex-math> </inline-formula>Torr was seen for the first few days, and no noticeable change afterward. The hermeticity of the thin-film encapsulated package was examined, and the vacuum level inside the package remained the same for the last 510 days. In addition to providing a stable hermetic package, the getter may be activated in-circuit by resistive heating in case of pressure increases after many years of operation. 2023-0034
In this article, we report a wafer-level packaged Pirani vacuum gauge using the proprietary InvenSense CMOS MEMS technology. The micro Pirani vacuum gauge features three serpentine-shaped molybdenum ...thermistors on the suspended silicon-on-insulator (SOI) bridges, while the wiring gap of each serpentine-shaped silicon microbridge is 1.6 <inline-formula> <tex-math notation="LaTeX">{ {\mu }}\text{m} </tex-math></inline-formula>. For the vacuum range of <inline-formula> <tex-math notation="LaTeX">5\times 10^{-{4}} </tex-math></inline-formula>-760 Torr, the CMOS MEMS Pirani gauge configured with a constant temperature interface circuit achieves a sensitivity of 0.414 V/Torr in a very fine vacuum regime, while its heating power is less than 21.3 mW. Moreover, the measured output of the micro Pirani gauge shows good agreement with a semi-empirical model, while the model predicts that the proposed Pirani gauge can measure a vacuum pressure as low as <inline-formula> <tex-math notation="LaTeX">2.6\times 10^{-{4}} </tex-math></inline-formula> Torr. The performance achieved by this Pirani vacuum gauge combined with its high level of integration makes it a promising Internet of Things (IoT) sensing node for vacuum monitoring in the industry.
Physical foundations for relativistic spacetimes are revisited in order to check at what extent Finsler spacetimes lie in their framework. Arguments based on inertial observers (as in the foundations ...of special relativity and classical mechanics) are shown to correspond with a double linear approximation in the measurement of space and time. While general relativity appears by dropping the first linearization, Finsler spacetimes appear by dropping the second one. The classical Ehlers–Pirani–Schild approach is carefully discussed and shown to be compatible with the Lorentz–Finsler case. The precise mathematical definition of Finsler spacetime is discussed by using the space of observers. Special care is taken in some issues such as the fact that a Lorentz–Finsler metric would be physically measurable only on the causal directions for a cone structure, the implications for models of spacetimes of some apparently innocuous hypotheses on differentiability, or the possibilities of measurement of a varying speed of light.
To achieve a wide range and high accuracy detection of the vacuum level, for example, in an encapsulated vacuum microcavity, a composite-type MEMS Pirani gauge has been designed and fabricated. The ...Pirani gauge consists of two gauges of different sizes connected in series, with one gauge having a larger heat-sensitive area and a larger air gap for extending the lower measurable limit of pressure (i.e., the high vacuum end) and the other gauge having a smaller heat-sensitive area and a smaller air gap for extending the upper measurable limit. The high-resistivity titanium metal was chosen as the thermistor; SiN
was chosen as the dielectric layer, considering the factors relevant to simulation and manufacturing. By simulation using COMSOL Multiphysics and NI Multisim, a range of measurement of 2 × 10
to 2 × 10
Pa and a sensitivity of 52.4 mV/lgPa were obtained in an N
environment. The performance of the fabricated Pirani gauge was evaluated by using an in-house made vacuum test system. In the test, the actual points of measurement range from 6.6 × 10
to 1.12 × 10
Pa, and the highest sensitivity is up to 457.6 mV/lgPa. The experimental results are better in the range of measurement, sensitivity, and accuracy than the simulation results. The Pirani gauge proposed in this study is simple in structure, easy to manufacture, and suitable for integration with other MEMS devices in a microcavity to monitor the vacuum level therein.
We have designed a hot-plate-type micro-Pirani vacuum gauge with a simple structure and compatibility with conventional semiconductor fabrication processes. In the Pirani gauge, we used a vanadium ...oxide (VOx) membrane as the thermosensitive component, taking advantage of the high temperature coefficient of resistance (TCR) of VOx. The TCR value of VOx is -2%K-1∼-3%K-1, an order of magnitude higher than those of other thermal-sensitive materials, such as platinum and titanium (0.3%K-1∼0.4%K-1). On one hand, we used the high TCR of VOx to increase the Pirani sensitivity. On the other hand, we optimized the floating structure to decrease the thermal conductivity so that the detecting range of the Pirani gauge was extended on the low-pressure end. We carried out simulation experiments on the thermal zone of the Pirani gauge, the width of the cantilever beam, the material and thickness of the supporting layer, the thickness of the thermal layer (VOx), the depth of the cavity, and the shape and size. Finally, we decided on the basic size of the Pirani gauge. The prepared Pirani gauge has a thermal sensitive area of 130 × 130 μm
, with a cantilever width of 13 μm, cavity depth of 5 μm, supporting layer thickness of 300 nm, and VOx layer thickness of 110 nm. It has a dynamic range of 10
~10
Pa and a sensitivity of 1.23 V/lgPa. The VOx Pirani was designed using a structure and fabrication process compatible with a VOx-based uncooled infrared microbolometer so that it can be integrated by wafer level. This work contains only our MEMS Pirani gauge device design, preparation process design, and readout circuit design, while the characterization and relevant experimental results will be reported in the future.
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