Hydrates for Cold Storage: Formation Characteristics, Stability, and Promoters

The potential of hydrates formed from R141b (CH3CCl2F), trimethylolethane (TME), and tetra-n-butylammonium bromide/tetra-n-butylammonium chloride (TBAB/TBAC) to be used as working substances for cold storage was investigated to provide a solution for unbalanced energy grids. In this study, the characteristics of hydrate formation, crystal morphology of hydrates, and the stability of hydrate in cyclic formation under 0.1 MPa and at 5 °C were carried out. It found that the ice had a positive effect on the hydrate formation under same conditions. Upon the addition of the ice cube, the induction time of R141b, TME, and TBAB/TBAC hydrates decreased markedly, and significantly high formation rates were obtained. Under magnetic stirring, the rate at which TBAB/TBAC formed hydrates was significantly lower than that when ice was used. In microscopic experiments, it was observed that the TBAB/TBAC mixture formed hydrates with more nucleation sites and compact structures, which may increase the hydrate formation rate. In the multiple cycle formation of TBAB/TBAC hydrates, the induction time gradually decreased with the increasing number of formation cycles and finally stabilized, which indicated the potential of the TBAB/TBAC hydrates for application in cold storage owing to their good durability and short process time for heat absorption and release.

Aquifer Storage and Recovery in Layered Saline Aquifers: Importance of Layer-Arrangements

Aquifer storage and recovery (ASR) refers to injecting freshwater into an aquifer and later withdrawing it. In brackish-to-saline aquifers, density-driven convection and fresh-saline water mixing lead to a reduced recovery efficiency (RE, i.e., the volumetric ratio between recovered potable water and injected freshwater) of ASR. For a layered aquifer, previous studies assume a constant hydraulic conductivity ratio between neighboring layers. In order to reflect the realistic formation of layered aquifers, we systematically investigate 120 layered heterogeneous scenarios with different layer arrangements on multiple-cycle ASR using numerical simulations. Results show that the convection (as is reflected by the tilt of the fresh-saline interface) and mixing phenomena of the ASR system vary significantly among scenarios with different layer arrangements. In particular, the lower permeable layer underlying the higher permeable layer restricts the free convection and leads to the spreading of salinity at the bottom of the higher permeable layer and early salt breakthrough to the well. Correspondingly, the RE values are different among the heterogeneous scenarios, with a maximum absolute RE difference of 22% for the first cycle and 9% for the tenth cycle. Even though the difference in RE decreases with more ASR cycles, it is still non-negligible and needs to be considered after ten ASR cycles. The method to homogenize the layered heterogeneity by simply taking the arithmetic and geometric means of the hydraulic conductivities among different layers as the horizontal and vertical hydraulic conductivities is shown to overestimate the RE for multiple-cycle ASR. The outcomes of this research illustrate the importance of considering the geometric arrangement of layers in assessing the feasibility of multiple-cycle ASR operations in brackish-to-saline layered aquifers.

1062 Are CT-KUB Requests Adequately Completed by Urologists in Emergency Settings?

Aim Imaging requests are an essential communication tool between urologists and radiologists. Poorly completed request forms, especially in acute settings, directly translates to substandard patient care. We aimed to evaluate and improve our request completion practice in emergency settings. Method 40 randomly selected CT-KUB images were reviewed to assess the completion of clinical background, question, patient data, location, and requester data. A multiple cycle audit followed by minor intra-departmental interventions were carried out over ten months to evaluate compliance. In December 2019, 55% and 52.5% of the requests lacked a good clinical history and question, respectively. The remaining three domains achieved the target of 100%. Subsequently, the literature and the audit data were shared and discussed, and a verbal agreement was made to improve practice. Result A re-audit revealed a 22.5% and 2.5% improvement in providing sufficient clinical background and questions. Findings were presented at an informal setting, and feedback was obtained on improving compliance. Simple posters or notices and occasional reminders were found as acceptable approaches. Following the implementation of feedback and orientation for joining junior doctors, a third audit cycle showed a significant improvement in compliance with 90% and 82.5%. A final cycle to assess the maintenance improvements in background and question provision was at a high of 97.5% and 90%. Conclusions CT-KUB request completion is essential in emergency settings to ensure optimal patient care. Improving compliance can be achieved using small interventions catered to the department, such as peer-to-peer discussions, reminder posters, and orientations.

“Don, doff, discard” to “don, doff, decontaminate”—FFR and mask integrity and inactivation of a SARS-CoV-2 surrogate and a norovirus following multiple vaporised hydrogen peroxide-, ultraviolet germicidal irradiation-, and dry heat decontaminations

Background As the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens. Aim We provide information on the effect of time-dependent passive decontamination (infectivity loss over time during room temperature storage in a breathable bag) and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination. Methods Masks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations. Results and discussion Infectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.

Impact of Assimilating Ground-Based Microwave Radiometer Data on the Precipitation Bifurcation Forecast: A Case Study in Beijing

In this study, the temperature and relative humidity profiles retrieved from five ground-based microwave radiometers in Beijing were assimilated into the rapid-refresh multi-scale analysis and prediction system-short term (RMAPS-ST). The precipitation bifurcation prediction that occurred in Beijing on 4 May 2019 was selected as a case to evaluate the impact of their assimilation. For this purpose, two experiments were set. The Control experiment only assimilated conventional observations and radar data, while the microwave radiometers profilers (MWRPS) experiment assimilated conventional observations, the ground-based microwave radiometer profiles and radar data into the RMAPS-ST model. The results show that in comparison with the Control test, the MWRPS test made reasonable adjustments for the thermal conditions in time, better reproducing the weak heat island phenomenon in the observation prior to the rainfall. Thus, assimilating MWRPS improved the skills of the precipitation forecast in both the distribution and the intensity of rainfall precipitation, capable of predicting the process of belt-shaped radar echo splitting and the precipitation bifurcation in the urban area of Beijing. The assimilation of the ground-based microwave radiometer profiles improved the skills of the quantitative precipitation forecast to a certain extent. Among multiple cycle experiments, the onset of 0600 UTC cycle closest to the beginning of rainfall performed best by assimilating the ground-based microwave radiometer profiles.

Multiple-Cycle Polymeric Extracellular Vesicle Precipitation and Its Evaluation by Targeted Mass Spectrometry

The multiple roles of extracellular vesicles (EVs) in pathogenesis have received much attention, as they are valuable as diagnostic and prognostic biomarkers. We employed polymeric EV precipitation to isolate EVs from clinical specimens to overcome the limitations of ultracentrifugation (UC), such as low protein yields, a large volume of specimens used, and time requirements. Multiple-cycle polymeric EV precipitation was applied to enhance the purity of the EV fractions with a small sample volume. Then, the purity was assessed using a multiple reaction monitoring (MRM) panel consisting of alpha-2-macroglobulin (A2M), thrombospondin 1 (THBS 1), galectin 3 binding protein (LGALS3BP), and serum albumin (ALB). For purity evaluation, the EV fractions isolated from blood specimens were subjected to shotgun proteomics and MRM-based targeted proteomics analyses. We demonstrate that the modified method is an easy and convenient method compared with UC. In the shotgun proteomics analysis, the proteome profile of EV fraction contains 89% EV-related proteins by matching with the EVpedia database. In conclusion, we suggest that multiple-cycle polymeric EV precipitation is not only a more effective method for EV isolation for further proteomics-based experiments, but may also be useful for further clinical applications due to the higher EV yield and low sample requirements.

High activity and low toxicity of a novel CD71-targeting nanotherapeutic named The-0504 on preclinical models of several human aggressive tumors

Background Ferritin receptor (CD71) is an example of a very attractive cancer target, since it is highly expressed in virtually all tumor types, including metastatic loci. However, this target can be considered to be inaccessible to conventional target therapies, due to its presence in many healthy tissues. Here, we describe the preclinical evaluation of a tumor proteases-activatable human ferritin (HFt)-based drug carrier (The-0504) that is able to selectively deliver the wide-spectrum topoisomerase I inhibitor Genz-644282 to CD71-expressing tumors, preventing the limiting toxic effects associated with CD71-targeting therapies. Methods CD71 expression was evaluated using flow cytometry and immunohistochemistry techniques. The-0504 antiproliferative activity towards several cancer cell lines was assessed in vitro. The-0504 antitumor efficacy and survival benefit were evaluated in different human tumors, which had been grown either as xenografts or patient-derived xenografts in mice. The-0504 toxicology profile was investigated in multiple-cycle repeat-dose study in rodents. Results In vitro studies indicate that The-0504 is highly specific for CD71 expressing cells, and that there is a relationship between CD71 levels and The-0504 anticancer activity. In vivo treatments with The-0504 showed a remarkable efficacy, eradicating several human tumors of very diverse and aggressive histotypes, such as pancreas, liver and colorectal carcinomas, and triple-negative breast cancer. Conclusions Durable disease-free survival, persistent antitumor responses after discontinuation of treatment and favorable toxicology profile make The-0504 an ideal candidate for clinical development as a novel, CD71-targeted, low-toxicity alternative to chemotherapy.

Purification of 89Sr from FBTR irradiated Yttria target by extraction chromatography using HDEHP impregnated XAD-7 resin

89Sr is used in bone pain palliative care of cancer patients and the same is being produced presently via the 89Y(n, p)89Sr reaction by irradiating yttria target in Fast Breeder Test Reactor (FBTR). An efficient separation method was standardized for the removal of bulk yttrium target by extraction chromatography using di(2-ethylhexyl) phosphoric acid (HDEHP) impregnated on XAD-7 resin. In the present paper, the extraction behavior of Sr(II) and Y(III) was studied as a function of the concentration of nitric acid in the aqueous phase and concentration of HDEHP in the resin phase. The separation of Sr(II) and Y(III) was standardized using the above resins and the method was subsequently applied satisfactorily for the removal of yttrium from the dissolver solution of FBTR irradiated yttria pellet towards the purification of 89Sr. A baseline separation of 89Sr and Y was achieved. Leaching and breakthrough capacity studies were evaluated for the resins and it was established that the stability and capacity of the resins were satisfactory. The breakthrough capacity was found to be 12 mg Y(III) per gram of the HDHEP resin whereas the leaching studies established that the resins are stable for multiple cycle of operations.

From “don, doff, and discard” to “don, doff, and decontaminate” – determination of filtering facepiece respirator and surgical mask integrity and inactivation of a SARS-CoV-2 surrogate and a small non-enveloped virus following multiple-cycles of vaporised hydrogen peroxide, ultraviolet germicidal irradiation, and dry heat decontamination

ABSTRACTBackgroundAs the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens.AimWe provide information on the effect of time-dependent passive decontamination at room temperature and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination.MethodsMasks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations.Results and DiscussionInfectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.