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Highlights • Mass fraction difference as the driving force for the mass transfer. • New variable to fit experimental data for absorption chillers. • Linear relation of cooling capacity to mass fraction difference. • Less deviation compared to characteristic temperature function. Abstract Absorption chillers are considered as heat transfer devices and hence most commonly modeled as heat transfer processes. The absorption of the refrigerant vapor though inherently involves mass transfer into the absorbent, which in comparison to the heat transfer usually is a slow transport process. Modeling absorption chillers, however, usually does not include this mass transfer process. This in fact neglects the dominant process in absorption chillers which is addressed in the present paper. [ABSTRACT FROM AUTHOR]

Patients with advanced hepatocellular carcinoma (aHCC) have a poor prognosis and high mortality. Nivolumab monotherapy demonstrated clinical benefit with an acceptable safety profile in patients with aHCC in the CheckMate 040 study. Five-year follow-up of the sorafenib-naive and sorafenib-experienced groups of CheckMate 040 is presented here. Patients received nivolumab monotherapy at dose levels of 0.1-10.0 mg/kg (dose-escalation phase) or 3 mg/kg (dose-expansion phase) every 2 weeks until disease progression or unacceptable toxicity. Primary endpoints were safety and tolerability (dose escalation), and objective response rate (ORR) by blinded independent central review (BICR) and by investigator as per RECIST version 1.1 (dose expansion). Eighty sorafenib-naive and 154 sorafenib-experienced patients were treated. Minimum follow-up in both groups was 60 months. ORR as per BICR was 20% [95% confidence interval (CI) 12% to 30%] and 14% (95% CI 9% to 21%) in the sorafenib-naive and sorafenib-experienced groups, respectively. Responses occurred regardless of HCC etiology or baseline tumor cell programmed death-ligand 1 (PD-L1) expression levels. Median overall survival (OS) was 26.6 months (95% CI 16.6-30.6 months) and 15.1 months (95% CI 13.0-18.2 months) in sorafenib-naive and sorafenib-experienced patients, respectively. The 3-year OS rates were 28% in the sorafenib-naive and 20% in the sorafenib-experienced groups; 5-year OS rates were 14% and 12%, respectively. No new safety signals were identified; grade 3/4 treatment-related adverse events were observed in 33% and 21% of patients in the sorafenib-naive and sorafenib-experienced groups, respectively. Biomarker analyses showed that baseline PD-L1 expression ≥1% was associated with higher ORR and longer OS compared with PD-L1 <1%. In the sorafenib-naive group, patients with OS ≥3 years exhibited higher baseline CD8 T-cell density compared with those with OS <1 year. With 5 years of follow-up, nivolumab monotherapy continued to provide durable clinical benefit with manageable safety in sorafenib-naive and sorafenib-experienced patients with aHCC. • At 5 years of follow-up, nivolumab monotherapy continued to provide durable clinical benefit in patients with aHCC. • ORR was 20% in the sorafenib (SOR)-naive group and 14% in the SOR-experienced group. • 3-year OS rates were 28% in the SOR-naive and 20% in the SOR-experienced groups; 5-year rates were 14% and 12%, respectively. • The safety profile of nivolumab monotherapy was manageable and no new safety signals were identified. • Higher ORR and longer OS were noted with baseline PD-L1 ≥1% versus <1% and were more prominent in the SOR-experienced group. [ABSTRACT FROM AUTHOR]

Reliably eliciting acute stress repeatedly over time is of indispensable value for research into stress vulnerability and for developing interventions aimed at increasing stress resiliency. Here, we evaluated whether the Maastricht Acute Stress Test (MAST), a potent stress protocol that combines physical and psychosocial stress components, can be used to reliably elicit subjective and neuroendocrine stress responses multiple times. Sixty healthy undergraduate participants were exposed to the MAST on three occasions, with intervals of three-weeks and one-month in between sessions. Results showed no significant signs of habituation or sensitization to the MAST in terms of subjective or physiological (salivary alpha-amylase and cortisol) stress reactivity. Fifty-nine percent of the sample displayed a significant physiological stress response (i.e., cortisol) to two MAST exposures and 57% to every MAST exposure. This study demonstrates that the MAST can be used to repeatedly induce significant stress responses. [ABSTRACT FROM AUTHOR]

The chemical transformations of the native oxide on stainless steel 309 S prior to pitting in anoxic near saturated geological Q3-brine were investigated by synchrotron radiation photoelectron spectroscopy (SRPES). A Cr-rich hydrated mixed iron-chromium-oxide exhibiting n-type semiconducting behavior is formed after wet polishing. Surface accumulation of holes in the metastable pitting potential region induces the hydroxylation of oxide bonds and a subsequent selective dissolution of iron. The open structure of the remaining surface chromium hydroxide facilitates the inward access of chloride and water. The inhibiting effect of sulfate is ascribed to the formation of stabilizing O-S-O bridges blocking chloride access. [Display omitted] • Structural and chemical changes of the passive film on austenitic steel prior to pitting. • The native oxide on austenitic steel consists of a hydrated Cr-rich mixed iron-chromium oxide. • The native oxide on austenitic steel behaves as n-type semiconductor. • Localized holes at discharged surface states induces the hydroxylation of oxide bonds. • The open structure of the outer hydrated Cr(OH)3 allows the penetration of chloride ions. [ABSTRACT FROM AUTHOR]

This study tests the performance of spectral mixture analysis (SMA) and multiple endmember spectral mixture analysis (MESMA) for estimation of green vegetation (GV), nonphotosynthetic vegetation (NPV), and soil fractions in the heterogeneous, structurally complex savannas of the western Kalahari using the Moderate Resolution Imaging Spectroradiometer (MODIS) nadir-bidirectional reflectance distribution function (BRDF) adjusted reflectance (NBAR) product. Extensive fieldwork took place during the dry and wet seasons of 2009 to 2011 at 15 sites distributed along a 950 km long transect, stretching across western Botswana, each site was visited once during the wet season and once during the dry season. Data collection included a traditional line-intercept transect (LPIT) and a new spectral line point intercept transect method (SLPIT) were used to test the performance of a variety of unmixing procedures (MESMA vs. SMA) and endmember models. The results for this structurally complex landscape are consistent with results from similar studies undertaken in more homogeneous areas. GV cover was retrieved much more accurately than NPV or soil cover. MESMA also produced estimates of fractional cover with less error than simple SMA. However, the errors observed are greater than those observed for more homogeneous environments. Unlike the line-point intercept method, which requires user interpretation of vegetation greenness, the new method uses spectral data collected across the entire reflected solar spectrum to derive estimates of GV, NPV and soil fractional cover through spectral unmixing. Our results show that that the SLPIT fractions generally agree better with remotely-derived fractions than the LPIT-derived fractions. However, remote sensing of GV, NPV, and soil fractional cover, especially in heterogeneous landscapes and at the spatial resolution of MODIS, remains challenging. Nonetheless, the data do show that at this resolution various unmixing methods have the potential to inform our understanding of ecosystem dynamics in these environments. [ABSTRACT FROM AUTHOR]

In the present study the Laplace transform is applied to the partial differential equations obtained from the differential energy and absorbate balances for the combined heat and mass transfer problem in laminar falling films with uniform film velocity. By means of the inverse Laplace transform an analytical solution is provided for the isothermal as well as for the adiabatic wall boundary condition. Temperature and mass fraction profiles across the film as well as the evolution of the absorbed mass flux as a function of the flow length are presented for the adiabatic wall condition as well as for the isothermal wall with different wall temperatures. Furthermore, the influence of the Lewis number on the absorbed mass flux is discussed. In addition, the present method allows to apply other wall boundary conditions than the isothermal or the adiabatic wall boundary, which will be addressed in a subsequent study. [ABSTRACT FROM AUTHOR]

Introduction Target temperature management (TTM) after cardiac arrest is recommended by international guidelines, which have been last updated in 2010. Here we investigate the status of implementation in a nationwide survey in Germany which took place in 2012. Methods We conducted a nationwide telephone survey including a total of 951 German intensive care units (ICUs). ICUs were identified by using the online registry for hospitals in Germany. A questionnaire was used for the interview about basic data of the intensive care unit and about details concerning use and implementation of TTM after cardiac arrest. Results The overall response rate was 91% (865/951). 86% (742/865) of ICUs used TTM after cardiac arrest and implementation peaked in 2010. 95% (702/736) of the ICUs using TTM perform treatment independently of the initial rhythm and 48% (355/738) apply TTM with the use of a feedback device for cooling and controlled re-warming. However, 22% (166/742) still use conventional methods like ice and cold infusion and only 61% (453/742) of the participants provided a written standard operating procedure (SOP). Conclusion With a delay of several years, TTM after cardiac arrest is now implemented in the majority of German ICUs. The moderate proportion of ICUs using SOPs for TTM and feedback-controlled cooling devices indicates the need of further improvement in post cardiac arrest care. [ABSTRACT FROM AUTHOR]

Grigor'eva and Nakoryakov presented an analytical solution for combined heat and mass transfer in laminar falling films by means of the Fourier method. The obtained solutions exhibited mathematical instabilities for small flow length, such as oscillations in the mass fraction profile and a mismatch of the inlet temperature. Grigor'eva and Nakoryakov explained these instabilities with the inconsistency of the inlet and boundary conditions and therefore an additional short term solution was introduced. In the present study the established tangent function, that is used to determine the eigenvalues within the Fourier method, is rearranged to a term without domain restrictions. Consequently, more eigenvalues are found, leading to a physical valid solution even for small flow lengths, matching the results of the short term solution perfectly. [ABSTRACT FROM AUTHOR]

Abstract: Since the late seventies of the 20th century, several analytical models for combined heat and mass transfer in laminar falling film absorption have been proposed. Nevertheless the analytical solutions obtained with the Fourier method for the coupled process are complex and for short flow length a certain instability occurs which have been explained with the inconsistency of the initial and boundary conditions. Therefore boundary layer models have been justified in order to solve the transfer problem for short flow length. Moreover a linear approximation of the phase equilibrium is required. The analytical solutions for heat and mass transfer presented in this paper are obtained by using the Laplace transform to solve the partial differential equations for an isothermal as well as impermeable wall. An originally unknown constant temperature and mass fraction boundary condition at the interface are set. The temperature and mass fraction profile across the film are obtained formally independently. In order to determine the yet unknown interface temperature and mass fraction the phase equilibrium and the interface energy balance are applied, using averaged gradients with regard to the streamwise coordinate. The interface temperature and mass fraction obtained with this procedure are interpreted and treated as mean values. From the known evolution of the mean interface temperature and mass fraction, the local values are derived by inverting the first mean value theorem for integration. The results show very good agreement to the established analytical solutions. The solving procedure does not depend on the input parameters such as the Lewis number for instance, which is needed in order to determine the eigenvalues within the Fourier method. Moreover arbitrary correlations for the phase equilibrium are applicable. The present solution is mathematically stable and offer explicit expressions in order to calculate the mean heat and mass fluxes directly. Therefore this solution is favourable to implement entire absorption process simulation, yet describing the coupled heat and mass transfer process comprehensively. [Copyright &y& Elsevier]