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Of the ~25 directly imaged planets to date, all are younger than 500Myr and all but 6 are younger than 100Myr1. Eps Ind A (HD209100, HIP108870) is a K5V star of roughly solar age (recently derived as 3.7-5.7Gyr2 and 3.5 - 1.3 + 0.8 Gyr3). A long-term radial velocity trend 4,5 as well as an astrometric acceleration6,7 led to claims of a giant planet2,8,9 orbiting the nearby star (3.6384±0.0013pc10). Here we report JWST coronagraphic images that reveal a giant exoplanet which is consistent with these radial and astrometric measurements, but inconsistent with the previously claimed planet properties. The new planet has temperature ~275K, and is remarkably bright at 10.65µm and 15.50µm. Non-detections between 3.5-5µm indicate an unknown opacity source in the atmosphere, possibly suggesting a high metallicity, high carbon-to-oxygen ratio planet. The best-fit temperature of the planet is consistent with theoretical thermal evolution models, which are previously untested at this temperature range. The data indicates that this is likely the only giant planet in the system and we therefore refer to it as "b", despite it having significantly different orbital properties than the previously claimed planet "b".
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INTRODUCTION AND OBJECTIVES: Using the assessment of satisfaction of patients of labour room services, the caregiver or policymakers can identify the gaps in the implemented programmes and health policies. This study was aimed to design a valid and reliable satisfaction questionnaire that will help in identifying the aspects of gaps that need improvement. METHODS: A facility and community-based observational cross-sectional study was conducted in the district of western Uttar Pradesh (India) between January 2019 and August 2020. Validation of the structured questionnaire with 34 dichotomous questions categorized under five subscales was performed by evaluating its validity and reliability. A total of 380 beneficiaries were selected from 48 government health facilities. RESULTS: The calculated Content validity index was calculated to be 9.5 which was adequate as per the guidelines. The reliability analysis of the questionnaire showed that the internal consistency was high with an overall Cronbach's alpha of 0.710. The variation in Cronbach's alpha on the elimination of any question from the questionnaire ranged from 0.676 to 0.767. The mean patient satisfaction score in the total surveyed population was 24.39±4.684 (total score=34) and there was a greater variation in the satisfaction score of infrastructure when compared with other subscales. CONCLUSION: The findings from this study support the reliability and validity of the patient satisfaction questionnaire as it is capable of evaluating the satisfaction in terms of delivery services provided in labour rooms as a whole.
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Instituciones de Salud , Satisfacción Personal , Humanos , Estudios Transversales , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
The abradable coatings had significantly enhanced turbomachinery performance by acting as a sacrificial seal between rotating blades and stationary casing. Further improvement in seal design to meet the higher energy demand and increase the service time has been the key challenge to solve in the gas turbine industry. Honeycomb seals have become the industry standard clearance seal technique due to their unique design and high structural strength with minimum weight. The present study proposes a concept to form a thermal shock resistance structure to achieve higher temperature capability and improve the reliability of high-temperature abradable seal structures for a hot gas path of turbines. A cavity layer of honeycomb seal structure made of SS 321 alloy was coated with advanced high-temperature ZrO2 + 7.5%Y2O3 + 4% polyester seal material using TriplexPro-210 plasma spray system. The integrity of a seal structure was assessed by a cross-sectional analysis and evaluation of the coating microstructure. Additionally, the micro-hardness test was performed to estimate coating fracture toughness, and finite element analysis was used to assess its thermo-mechanical performance. The concept proposed in this study should be further validated to develop the most capable innovative technology for advanced gas turbine abradable seal structures.
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Giant exoplanets on wide orbits have been directly imaged around young stars. If the thermal background in the mid-infrared can be mitigated, then exoplanets with lower masses can also be imaged. Here we present a ground-based mid-infrared observing approach that enables imaging low-mass temperate exoplanets around nearby stars, and in particular within the closest stellar system, α Centauri. Based on 75-80% of the best quality images from 100 h of cumulative observations, we demonstrate sensitivity to warm sub-Neptune-sized planets throughout much of the habitable zone of α Centauri A. This is an order of magnitude more sensitive than state-of-the-art exoplanet imaging mass detection limits. We also discuss a possible exoplanet or exozodiacal disk detection around α Centauri A. However, an instrumental artifact of unknown origin cannot be ruled out. These results demonstrate the feasibility of imaging rocky habitable-zone exoplanets with current and upcoming telescopes.
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With this Feature Article we review, for the first time, the development of DNA-host conjugates-a nascent yet rapidly growing research focus within the ambit of DNA supramolecular chemistry. Synthetic hosts (such as cyclodextrins, cucurbiturils, and calixarenes) are well-suited to be partnered with DNA, since DNA assembly and host-guest binding both thrive in aqueous media, are largely orthogonal, and exhibit controllable and input-responsive properties. The covalent braiding of these two supramolecular synthons thus leads to advanced self-assemblies and nanostructures with exciting function that range from drug delivery agents to input-triggered switches. The latter class of DNA-host conjugates have been demonstrated to precisely control protein activity, and have also been used as modulable catalysts and versatile biosensors.
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ADN/química , Compuestos Macrocíclicos/química , Nanoestructuras/química , Animales , Técnicas Biosensibles/métodos , Calixarenos/síntesis química , Calixarenos/química , Ciclodextrinas/síntesis química , Ciclodextrinas/química , ADN/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Técnicas de Transferencia de Gen , Humanos , Compuestos Macrocíclicos/síntesis química , Modelos Moleculares , Nanotecnología/métodosRESUMEN
The present study was formulated to find out the status of important season related thermal stress biomarkers of pure-bred (Hampshire) and crossbred (50% Hampshire × 50% local) pigs under the agro-climatic condition of Assam State, India. The experiment was also aimed to study the role of different level of energy ration (110, 100, and 90% energy of NRC feeding standard for pig) in variation of physiological and biochemical parameters in two genetic groups of pigs in different seasons. The metabolizable energy value were 3260, 2936.5, and 3585.8 kcal/kg in grower ration and 3260.2, 2936.6, and 3587 kcal/kg in finisher ration for normal energy (NE), low energy (LE) and high energy (HE), respectively. Both the genetic group of animals were housed separately under intensive system of management. Each pen was measuring 10' × 12' along with an outer enclosure. Six weaned piglets (almost similar body weight of average 10.55 kg) of each group were kept in a separate pen. However, after attainment of 35 kg body weight, the animals of a group were divided in two pens of three animals each. The present experiment indicated that average ambient temperature during summer months (27.33-29.51 °C) was above the comfort zone for pigs (22 °C). The significantly (P < 0.01) higher relative humidity (RH) (%) was recorded in outdoor environment (87.26-91.10%) and in the morning time (86.60-91.10%). The temperature humidity index (THI) during the study period was found to be indicative of thermal stress to the experimental animals during summer (79.55-82.56). Physiological parameters viz., respiration rate (RR) and rectal temperature (RT) were significantly (P < 0.01) higher in summer season (43.75-72.12 breaths/min. and 102.29-103.23 °F) and non-significantly higher values were recorded in Hampshire pigs. It was also found that the significantly (P < 0.01) lower RR as well as RT was recorded in the pigs fed with high energy (HE) ration during summer season. Serum triiodothyronine (T3) and thyroxine (T4) concentrations were significantly (P < 0.01) lower during summer, while both the genetic groups showed significantly (P < 0.01) higher concentration of serum cortisol during summer season. It was also observed that thyroid hormone and cortisol concentrations were maintained in groups of pig fed vegetable oil incorporated HE diet during summer. From the present study, it is found that the increasing the energy level of the ration might be helpful to minimize the effects of thermal stress during summer.
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Ingestión de Energía , Humedad , Hidrocortisona/sangre , Estaciones del Año , Destete , Animales , Biomarcadores/sangre , Temperatura Corporal/fisiología , Peso Corporal , Dieta/veterinaria , Femenino , India , Masculino , Porcinos , Temperatura , Hormonas Tiroideas/sangre , Clima TropicalAsunto(s)
Donantes de Sangre , Hemocromatosis , Obtención de Tejidos y Órganos/métodos , Femenino , Humanos , MasculinoRESUMEN
Straight chain amide N,N-dihexyloctanamide (DHOA) has been found to be a promising alternative extractant to tri-n-butyl phosphate (TBP) for the reprocessing of irradiated uranium- and thorium-based fuels. Unlike TBP, DHOA displays preferential extraction of Pu(IV) over U(VI) at higher acidities (≥3 M HNO3) and poor extraction at lower acidities. Density functional theory (DFT) based calculations have been carried out on the structures and relative binding energies of U(VI) and Pu(IV) with the extractant molecules. These calculations suggest that the differential hardness of the two extractants is responsible for the preferential binding/complexation of TBP to uranyl, whereas the softer DHOA and the bulky nature of the extractant lead to stronger binding/complexation of DHOA to Pu(IV). In conjunction with quantum chemical calculations, small angle neutron scattering (SANS) measurements have also been performed for understanding the stoichiometry of the complex formed that leads to relatively lower extraction of Th(IV) (a model for Pu(IV)) as compared to U(VI) using DHOA and TBP as the extractants. The combined experimental and theoretical studies helped us to understand the superior complexation/extraction behavior of Pu(IV) over U(VI) with DHOA.
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The presence of long-lived radionuclides in natural aquatic systems is of great environmental concern in view of their possible migration into biospheres of mankind. Trivalent actinides such as (241/243)Am can contribute a great deal to radioactivity for several thousand years. This migration is significantly influenced by various factors such as pH, complexing ions present in aquatic environments, and the sorption of species involving radionuclides by sediments around water bodies. Clay minerals such as bentonite are known to be highly efficient in radionuclide retention and hence are suitable candidates for backfill materials. This study presents experimental results on the interaction of Eu(iii) and Gd(iii) (chemical analogs of Am(iii) and Cm(iii)) with bentonite clay under varying experimental conditions of contact time, pH, and the presence of complexing anions such as humic acid (HA) and citric acid (cit). The sorption of HA on bentonite decreased with increasing the pH from 2 to 8, which was attributed to electrostatic interactions between HA and the bentonite surfaces. The sorption of Eu(iii) on bentonite colloids showed marginal variation with pH (>95%). However, a decrease in Eu(iii) sorption was observed in the presence of HA beyond pH 5 due to the increased aqueous complexation of Eu(iii) with deprotonated HA in the aqueous phase. The complexation of Eu(iii) with citrate ions was studied using Time Resolved Laser induced Fluorescence Spectroscopy (TRLFS) to explain the sorption data. Extended X-ray absorption fine structure (EXAFS) and electron paramagnetic resonance (EPR) investigations were carried out to understand the local chemical environment surrounding Eu(iii) and Gd(iii) (EPR probe) sorbed on bentonite under different experimental conditions. Surface complexation modelling shows the predominant formation of ≡XOEu(+2) (silanol) up to pH < 7, and beyond which ≡YOEu(OH)(+) (aluminol) is responsible for the quantitative sorption of Eu(iii) onto bentonite in the studied pH range.
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Bentonita/química , Sustancias Húmicas , Metales/química , Modelos Químicos , Concentración de Iones de Hidrógeno , Iones/química , Espectrometría de Fluorescencia , Espectroscopía de Absorción de Rayos XRESUMEN
INTRODUCTION: Incidence of sudden cardiac death (SCD) has been steadily increasing all over the world. While knowing the cause of SCD is one of the favorites of the physicians involved with these cases, it is very difficult and challenging task for the forensic physician. The present report is a prospective study regarding cause of SCDs on autopsy examination in four-year period, Bangalore, India. METHODS: The present prospective study is based on autopsy observations, carried out for four-year period from 2008 to 2011, and analyzed for cause of SCDs. The cases were chosen as per the definition of sudden death and autopsied. The material was divided into natural and unnatural groups. Finally, on histopathology, gross examination, hospital details, circumstantial, and police reports the cause of death was inferred. RESULTS: A total of 2449 autopsy was conducted of which 204 cases were due to SCD. The highest SCDs were reported in 50-60 years age group (62.24%; n-127), followed closely by the age group 60-69 (28.43%; n-58). Male to female ratio was around 10:1. The maximum number of deaths (n=78) was within few hours (6 hours) after the onset of signs and symptoms. In 24 (11.8%) cases major narrowing was noted in both the main coronaries, in 87 (42.6%) cases in the left anterior descending coronary artery (LAD), and in 18 (51.5%) cases in the right coronary artery (RCA). The major cardiac pathology resulting in sudden death was coronary artery disease (n-116; 56.86%) and myocardial infarction (n-104; 50.9%). most of the SCDs occurred in the place of residence (n-80; 39.2%) followed closely by death in hospital (n-49; 24.01%). CONCLUSION: Coronary occlusion was the major contributory cause of sudden death with cardiac origin and the highest number of deaths were reported in the age 50-59 years with male to female ratio of 10:1.
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There are contradicting reports on the thermodynamics of cation-cation interactions (CCIs; inner/outer sphere) involving NpO2(+) and UO2(2+). This paper revisits CCIs of NpO2(+) (2 × 10(-4) M) under varying conditions such as reaction time, nitric acid (2 × 10(-3)-4 M HNO3)/uranium (up to 1.2 M) concentrations, and temperature (283-343 K) by spectrophotometric measurements. This study reports for the first time the appearance of a signature peak of Np(IV) (â¼964 nm) in addition to NpO2(+) (980 nm) and the NpO2(+)-UO2(2+) complex (992 nm). For a pure NpO2(+) solution at 4 M HNO3, there is a gradual increase in Np(IV) peak intensity with increasing temperature and correspondingly the Np(V) peak diminishes. The CCIs are more favored at higher uranium concentrations. However, the intensity of the 992 nm peak decreases steadily with increasing temperature suggesting the exothermic nature of the complexation process. The thermodynamic data and reported structural studies indicate the formation of an inner-sphere complex under the conditions of this study. In addition, the spectral changes also suggest the formation of Np(IV) even in the presence of uranium at elevated temperatures. Solvent extraction studies using 1.1 M TBP and 1.1 M DHOA solutions in n-dodecane show that NpO2(+)-UO2(2+) complexes are extractable leaving NpO2(+) in the aqueous phase.
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Small-angle neutron scattering (SANS) studies were carried out to compare the aggregation behavior of 1.1 M solutions of tributyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) dissolved in different deuterated diluents, viz., n-dodecane, chloroform, and benzene, during the extraction of Th(IV) from nitric acid medium. The scattering data was treated using the Baxter sticky spheres model. The third phase formed in the case of DHOA displayed higher aggregation tendency compared to that of TBP. These studies have demonstrated that the nature of the diluents plays an important role in the aggregation behavior of the extracted species (reverse micelles). No third phase was observed in the case of chlorinated and aromatic diluents like chloroform and benzene during the extraction of Th(IV) from nitric acid medium. Theoretical calculations were also performed to gain insights into the binding of thorium nitrate with TBP and DHOA models. These calculations suggest that two to three molecules of both DHOA and TBP strongly coordinate to Th(NO3)4. It is noted that the highly charged Th(IV) cations are screened by nitrates and extractants which enables the interaction of second unit of such complex through noncovalent interactions.
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UREX process has been proposed for selective extraction of U(VI) and Tc(VII) from nitric acid medium (â¼1M HNO3) using tri-n-butyl phosphate (TBP) as extractant and retaining Pu, Np and fission products in the aqueous phase. The feasibility of the use of luminescence spectroscopy as a technique to understand the complexation of trivalent f-elements cations viz. Eu(III) and Tb(III) with acetohydroxamic acid (AHA) in nitric acid medium has been examined. The luminescence lifetimes for the 1×10(-3)M Eu(III) and AHA complex system decreased with increased AHA concentration from 116±0.2µs (no AHA) to 1.6±0.1µs (0.1M AHA) which was attributed to dynamic quenching. The corrected fluorescence intensities were used to calculate the stability constant (log K) for the formation of 1:1 Eu(3+)-AHA complex as 1.42±0.64 under the conditions of this study. By contrast, the Tb(III)-AHA system at pH 3 (HNO3) did not show any significant variation in the life times of the excited state (364±9µs) suggesting the absence of dynamic quenching. The spectral changes in Tb(III)-AHA system showed the formation of 1:1 complex (log K: 1.72±0.21). These studies suggest that the extent of AHA complexation with the rare earth elements will be insignificant as compared to tetravalent metal ions Pu(IV) and Np(IV) under UREX process conditions.
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Europio/química , Ácidos Hidroxámicos/química , Luminiscencia , Nitratos/química , Terbio/química , Espectrometría de Fluorescencia , TermodinámicaRESUMEN
The present study was conducted to know the smallholder pig production system in tribal areas of Sikkim State, India. Two hundred tribal farmers were selected randomly from the North and East District of the state. Information on socio-economic characteristics of farmers (gender, occupation, educational status, and farming experience), management practices, disease prevalence, and economics in pig production was collected. The study recorded the mean land holding as 1.2 ± 0.8 ha, and the number of pigs per farm was 5.0 ± 0.28. Pigs were mainly kept as a source of income, and 70 % of farmers reared crossbreed pigs. Ninety percent (90 %) of respondents practiced the intensive system of management whereby kitchen wastes along with cooked mixture comprising maize bhusa, mustard oil cake, pseudostem of banana, tuber, stem, and plant leaves were used to feed their animals. About 40.5 % of farmers procured their breeding stock from government farms that had good records and utilized veterinary services like timely vaccination and deworming. The diseases prevalent in the study area were swine fever, diarrhea, helminthoses, sarcoptic mange, pneumonia, etc. The litter sizes at birth (local, 4.3 ± 0.45; crossbreed, 7.2 ± 0.33), at weaning (local, 2.79 ± 0.24; crossbreed, 6.1 ± 0.21), and age at first farrowing (local, 365.39 ± 7.96 days; crossbreed, 337.24 ± 8.79 days) were recorded. Production costs of meat extracted from local and crossbred pigs were 1.08 $/kg and 0.86 $/kg, respectively.
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Alimentación Animal/análisis , Crianza de Animales Domésticos/métodos , Carne/economía , Reproducción , Enfermedades de los Porcinos/epidemiología , Porcinos , Crianza de Animales Domésticos/economía , Animales , Dieta/veterinaria , Tamaño de la Camada , Prevalencia , Sikkim/epidemiología , Encuestas y Cuestionarios , Porcinos/crecimiento & desarrollo , Porcinos/fisiología , Enfermedades de los Porcinos/etiologíaRESUMEN
Laser desorption/ionization-time-of-flight mass spectrometry (LDI-ToF-MS) has been applied to identify and characterize the organic phase species formed during the extraction of thorium nitrate by 1.1 M tri-n-butyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) solutions in n-dodecane. The aqueous phase thorium concentrations (at 4M HNO3) have been suitably chosen to get Loaded organic phases with/without third-phase. The extracted species have been characterized for the first time using LDI-ToF-MS. The results show feasibility of the use of this technique for understanding the extraction mechanisms and third-phase formation behavior of different extractants. The different chemical species observed using this technique are consistent with those observed by small-angle neutron scattering (SANS).
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The two long alkyl chain derivatives of diglycolamide (DGA), viz. N,N,N',N'-tetraoctyl diglycolamide (TODGA) and N,N,N',N'-tetra(2-ethylhexyl)-diglycolamide (T2EHDGA) have been found promising for actinide partitioning from high-level waste. The solvent extraction studies have suggested the participation of three to four DGA molecules in the extracted complex of trivalent actinides and lanthanides. However, coordination of 3-4 tridentate DGA ligands with trivalent f-elements seems to be unusual due to restricted coordination sites in these metal ions. Nonetheless, the extraction data have been explained in view of the formation of aggregates of these ligands in the organic phase. Small Angle Neutron Scattering (SANS) measurements were carried out to investigate the aggregation behavior of DGA ligands in deuterated n-dodecane. The aggregation of DGA molecules was facilitated by the presence of acid. However, the presence of nitrate ions in the aqueous phase had no significant effect on the aggregation of DGA. Similarly, the presence of metal ions such as Sr(II) or Eu(III) marginally affected the aggregation tendency of DGA molecules. TODGA displayed higher aggregation tendency than that of T2EHDGA. The extraction data of trivalent f-elements were in conformity with the aggregation tendency of the two DGA ligands.
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Glicolatos/química , Alcanos/química , Glicolatos/síntesis química , Glicolatos/aislamiento & purificación , Estructura Molecular , Dispersión del Ángulo Pequeño , Difracción de Rayos XRESUMEN
The introduction of robotic medical assistance in biopsy and stomach cavity exploration is one of the most important milestones in the field of medical science. The research is still in its infancy and many issues like limitations in dexterity, control, and abdominal cavity vision are the main concerns of many researchers around the globe. This paper presents the design aspects and the kinematic analysis of a 4 degrees of freedom (DOF) hyper-redundant in-vivo robot for stomach biopsy. The proposed robot will be inserted through the tool channel of a conventional 4-DOF endoscope and this will increase the dexterity and ease in reaching the furthest parts of the stomach beyond the duodenum. Unlike the traditional biopsy tool, the present design will enhance dexterity due to its 4 DOF in addition to the endoscope's DOF. The endoscope will be positioned at the entrance to the stomach in the esophagus and the robot will move to the desired position inside the stomach for biopsy and exploration. The current robot is wire-actuated and possesses better maneuverability. The forward kinematic analysis of the proposed robot is presented in this paper.
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Crown ethers dissolved in suitable medium are well known to promote the extraction of alkali (M(+)) and alkaline-earth (M(2+)) cations from aqueous to organic phases. Di-tert-butyl-cyclohexano18crown6 (DTBDCH18C6) has been identified as an effective and selective extractant for Sr(II) from nitric acid medium. An attempt was made to evaluate the feasibility of (85,89)Sr recovery from synthetic soil samples (0.5 g; particle size: <100 µm) by SFE route (pressure: 200 kg/cm(2); T: 40 °C) employing DTBDCH18C6 dissolved in methanol/nitric acid medium as phase modifier. The effect of various experimental parameters such as (i) dynamic/static mode of extraction, (ii) time of equilibration (15-150 min during static mode of extraction using 3 mL of modifier), (iii) nitric acid concentration (1-6M), (iv) picrate as counter-anion, and (v) crown ether concentration in the modifier phase (2×10(-4)-2×10(-3) M) on Sr(II) extraction was studied. Based on these studies, 2×10(-4) M DTBDCH18C6 dissolved in methanol/4M HNO(3) was chosen as modifier and 30 min as equilibration time for batch mode employing 3 mL modifier solution in the static mode. Three successive batches employing 3 mL modifier solution (after each extraction stage) showed near quantitative recovery (>95%) of (85,89)Sr from soil samples. Dynamic mode extraction using 2×10(-4) M DTBDCH18C6 dissolved in methanol/4M HNO(3) as modifier suggested that near quantitative recovery (>95%) of (85,89)Sr could be achieved within 1h. By contrast, ~10% (137)Cs extraction was observed from soil samples under identical experimental conditions. These studies demonstrate the potential of the SFE technique for the analysis of (90)Sr in different environmental samples.
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STUDY AIMS: Following carpal tunnel release (CTR), only very modest correlations have been found between subjective symptoms and function indexes compared to neurophysiological measures. The objective of this study was to evaluate this relationship by comparing the self-administered Boston symptom severity score and function severity score questionnaire against nerve conduction studies (NCS) before and after CTR using two different electrophysiological techniques. PATIENTS AND METHODS: Carpal tunnel release was performed in 51 patients (62 hands). Pre- and postoperative NCS were evaluated using both conventional neurophysiological methods and by means of a new hand-held device. RESULTS: Preoperatively there was almost no correlation between symptom severity and function scores and NCS results. Following surgery however, both symptom severity and function showed a modest, but significant improvement in their correlation to NCS (at highest r=0.405, P<0.01). This improvement in the relation of subjective measures to neurophysiological results was seen in both median nerve sensory and motor conduction as well as in ulnar nerve motor conduction. CONCLUSIONS: In addition to median-nerve dysfunction, it might be suggested that ulnar nerve changes can contribute to symptoms of carpal tunnel syndrome in patients. Several associations were found using a median-ulnar sensory latency difference in the finger-wrist segment and a sensory conduction difference in the palm to wrist segment. Significant correlations were established by both conventional NCS and the new hand-held device.