Gas-Phase Temperature Mapping of Evaporating Microdroplets

Evaporation is a ubiquitous and complex phenomenon of importance to many natural and industrial systems. Evaporation occurs when molecules near the free interface overcome intermolecular attractions with the bulk liquid. As molecules escape the liquid phase, heat is removed, causing evaporative cooling. The influence of evaporative cooling on inducing a temperature difference with the surrounding atmosphere as well as within the liquid is poorly understood. Here, we develop a technique to overcome past difficulties encountered during the study of heterogeneous droplet evaporation by coupling a piezo-driven droplet generation mechanism to a controlled micro-thermocouple to probe microdroplet evaporation. The technique allowed us to probe the gas-phase temperature distribution using a micro-thermocouple (50 mu m) in the vicinity of the liquid-vapor interface with high spatial (+/- 10 mu m) and temporal (+/- 100 ms) resolution. We experimentally map the temperature gradient formed surrounding sessile water droplets having varying curvature dictated by the apparent advancing contact angle (100 degrees less than or similar to theta less than or similar to 165 degrees). The experiments were carried out at temperatures below and above ambient for a range of fixed droplet radii (130 mu m less than or similar to R less than or similar to 330 mu m). Our results provide a primary validation of the centuries-old theoretical framework underpinning heterogeneous droplet evaporation mediated by the working fluid, substrate, and gas thermophysical properties, droplet apparent contact angle, and droplet size. We show that microscale droplets residing on low-thermal-conductivity substrates such as glass absorb up to 8x more heat from the surrounding gas compared to droplets residing on high-thermal-conductivity substrates such as copper. Our work not only develops an experimental understanding of the heat transfer mechanisms governing droplet evaporation but also presents a powerful platform for the study and characterization of liquid-vapor transport at curved interfaces wetting and nonwetting advanced functional surfaces

Prediction of the Levodopa Challenge Test in Parkinson's Disease Using Data from a Wrist-Worn Sensor.

The response to levodopa (LR) is important for managing Parkinson's Disease and is measured with clinical scales prior to (OFF) and after (ON) levodopa. The aim of this study was to ascertain whether an ambulatory wearable device could predict the LR from the response to the first morning dose. The ON and OFF scores were sorted into six categories of severity so that separating Parkinson's Kinetigraph (PKG) features corresponding to the ON and OFF scores became a multi-class classification problem according to whether they fell below or above the threshold for each class. Candidate features were extracted from the PKG data and matched to the class labels. Several linear and non-linear candidate statistical models were examined and compared to classify the six categories of severity. The resulting model predicted a clinically significant LR with an area under the receiver operator curve of 0.92. This study shows that ambulatory data could be used to identify a clinically significant response to levodopa. This study has also identified practical steps that would enhance the reliability of this test in future studies

The Use of Data from the Parkinson's KinetiGraph to Identify Potential Candidates for Device Assisted Therapies

Device-assisted therapies (DAT) benefit people with Parkinsons Disease (PwP) but many referrals for DAT are unsuitable or too late, and a screening tool to aid in identifying candidates would be helpful. This study aimed to produce such a screening tool by building a classifier that models specialist identification of suitable DAT candidates. To our knowledge, this is the first objective decision tool for managing DAT referral. Subjects were randomly assigned to either a construction set (n = 112, to train, develop, cross validate, and then evaluate the classifier's performance) or to a test set (n = 60 to test the fully specified classifier), resulting in a sensitivity and specificity of 89% and 86.6%, respectively. The classifier's performance was then assessed in PwP who underwent deep brain stimulation (n = 31), were managed in a non-specialist clinic (n = 81) or in PwP in the first five years from diagnosis (n = 22). The classifier identified 87%, 92%, and 100% of the candidates referred for DAT in each of the above clinical settings, respectively. Furthermore, the classifier score changed appropriately when therapeutic intervention resolved troublesome fluctuations or dyskinesia that would otherwise have required DAT. This study suggests that information from objective measurement could improve timely referral for DAT

Collecting vaginal discharge with or without speculum in diagnosing gynecological infections

BackgroundCurrently, with the omission of speculum in vaginal examination, noninvasive methods to diagnose gonorrhea and chlamydia by urine tests are available. It is now possible to diagnose bacterial vaginosis, candidiasis and trichomoniasis by vaginal swabs directly without speculum examination.  PurposeThis quasi-experimental study was conducted to compare the results of two sampling methods with or without speculum of vaginal discharge in diagnosing gynecological infections. Methods100 patients between 18-49 with vaginal discharge and other manifestations of vaginosis referring to gynecology clinic of Taleghani hospital were selected by convenience sampling method. One vaginal swab was used before examination with speculum and one during it to collect the discharge for diagnosing trichomoniasis, candidiasis and bacterial vaginosis. Both samples were observed under microscope by blind method and compared in terms of sensitivity. ResultsSensitivities of discharge collection with and without speculum for diagnosing bacterial vaginosis, trichomoniasis and candidiasis were %81 and %71, 69% and %62.5, and %86 and %77 respectively with no significant difference. Agreements between the two methods for the diagnosis of bacterial vaginosis, trichomoniasis and candidiasis were 0.89, 0.85 and 0.72 respectively. ConclusionGynecological infections can be detected without examination by speculum. This is helpful for those who fear from this type of examination and delay their visits.  Keywords: Gynecological infections, Sexually transmitted disease (STD), Pelvic in flammatory disease (PID), Vaginiti

The Comparison of Two Methods of Vaginal Discharge with and without Speculum Examination Diagnosis of Trichomonas Infection

Background and Aim: Evaluation for STIs requires speculum examination. It is sometimes uncomfortable and rejected by many patients. Speculum examination often is impractical or not available in remote areas. Recently, it is possible to omit the speculum examination and noninvasively diagnose for Chlamydia and gonorrheal infections from urine sample. This comparison study was conducted by collected vaginal specimens directly without performing a speculum examination for the diagnosis of trichomonas infections.The aim of this study was comparison of two methods of vaginal discharge collection with and without speculum examination for diagnosis of the trichomonas infection.Materials and Methods: We examined 100 patients with vaginal discharge to the gynecology clinic of the Taleghani hospital. Two vaginal swab were collected from vaginal discharge of patients before and during speculum examination for diagnosis of trichomoniasis. Both of vaginal specimens were tested with blinded microscopic. Compared collection methods sensitivities, specificity, positive predictive value, negative predictive value and accuracy of both methods was compared.Results: Sensitivities, specificity, positive predictive value, negative predictive value and accuracy of speculum collection methods were 69%, 99%, 92% ,94% and 93% for trichomoniasis respectively. Sensitivities, specificity, positive predictive value, negative predictive value and accuracy of nonspeculum collection methods were 62.5%, 99%, 91%, 93% and 92% for trichomoniasis respectively. The differences between methods was not statistically significant (P= NS). There was a very good agreement between both methods for diagnosis of trichomoniasis (KAPPA= o.85).Conclusions: We have demonstrated the benefit of nonspeculum vaginal specimens for the diagnosis of trichomoniasis. This technique has applicability for studies involving the epidemiology of vaginal infection as well as for home diagnostic testing ,elder and pregnant women respectively

Simultaneous Spectrophotometric Determination of Amitriptyline Hydrochloride and Chlordiazepoxide in Pharmaceutical Tablets by Multivariate Calibration Method

The multivariate calibration method, partial least square regression (PLS) was applied for the simultaneous spectrophotometry determination of amitriptyline hydrochloride (AMT) and chlordiazepoxide (CHL) in their mixtures. The parameters of chemometric technique were optimized and the proposed method was validated with synthetic samples and applied to analyze these drugs in pharmaceutical products with good accuracy and precision. The results were compared with those given by United State Pharmacopoeia method. The square of the correlation coefficients (R2) for predicted AMT and CHL with the proposed method in a test sample were 0.9951 and 0.9897 respectively. The relative standard deviation for commercial tablets in the proposed method and USP standard method were 0.42 and 2.61%, respectively

The Level of Islamic Religiosity of the Local Community and Corporate Environmental Responsibility Disclosure: Evidence from Iran

The purpose of this paper is to examine the relationship between the Islamic religiosity of the local community and the level of corporate environmental responsibility disclosure (CERD) in Iran, an example of an Islamic country. This paper also examines the moderating role of firm size, family ownership, and state ownership. This study is conducted using a sample of 952 observations across firms listed on the Tehran Stock Exchange. The results indicate that CERD increases with an increase in the level of Islamic religiosity of the province where the firm is located. Also, findings reveal that firm size and family ownership strengthen the aforementioned relationship. However, we provide evidence suggesting that state ownership weakens the positive relationship between the Islamic religious atmosphere and CERD. The results of this research present a new insight suggesting that the Islamic values governing a local community can significantly affect executives’ decisions regarding disclosures, particularly resulting in a decrease in executives’ selfishness and encouraging them to disclose more information about environmental responsibilities

The use of accelerometry as a tool to measure disturbed nocturnal sleep in Parkinson's disease

Sleep disturbances are common in Parkinson's disease (PD). We used the Parkinson's KinetiGraph (PKG), an objective movement recording system for PD to assess night time sleep in 155 people aged over 60 and without PD (controls), 72 people with PD (PwP) and 46 subjects undergoing a Polysomnogram (PSG: 36 with sleep disorder and 10 with normal sleep). The PKG system uses a wrist worn logger to capture acceleration and derive a bradykinesia score (BKS) every 2 min over 6 days. The BKS ranges from 0-160 with higher scores associated with lesser mobility. Previously we showed that BKS > 80 were associated with day time sleep and used this to produce scores for night time sleep: Efficiency (Percent time with BKS > 80), Fragmentation (Average duration of runs of BKS > 80) and Sleep Quality (BKS > 111 as a representation of atonia). There was a fair association with BKS score and sleep level as judged by PSG. Using these PKG scores, it was possible to distinguish between normal and abnormal PSG studies with good Selectivity (86%) and Sensitivity (80%). The PKG's sleep scores were significantly different in PD and Controls and correlated with a subject's self-assessment (PDSS 2) of the quality, wakefulness and restlessness. Using both the PDSS 2 and the PKG, it was apparent that sleep disturbances were apparent early in disease in many PD subjects and that subjects with poor night time sleep were more likely to have day time sleepiness. This system shows promise as a quantitative score for assessing sleep in Parkinson's disease

Prediction of the Levodopa Challenge Test in Parkinson's Disease Using Data from a Wrist-Worn Sensor (vol 19, 5153, 2019)

The authors wish to make the following erratum to this paper [...]