Supramolecular anion recognition in water: synthesis of hydrogen-bonded supramolecular frameworks

The interaction of tetratopic amidinium-containing receptors with terephthalate anions leads to porous framework materials assembled through charge-assisted hydrogen bonds. The frameworks form in good yield within minutes in water at room temperature, but no framework material is obtained if other anions (Cl-, Br-, NO3-, SO42- or isophthalate2-) are used in place of terephthalate. Two forms of the framework can be prepared: one with a connected pore network, and a more dense phase with discrete voids. We demonstrate that these are the kinetic and thermodynamic products, respectively. Either framework can be prepared independently and can be converted to the other form in response to stimuli. Furthermore, the frameworks can be controllably disassembled and reassembled in response to acid/base triggers suggesting that this new class of materials may have applications in the selective encapsulation and release of guests.Mahbod Morshedi, Michael Thomas, Andrew Tarzia, Christian J. Doonan and Nicholas G. Whit

Improving scour risk management for Iowa by utilizing improved flood frequency estimates and modified HYRISK

Two approaches can be utilized for determination of the design flood discharge depending on the presence of the USGS gages in the streams that bridges are built on. For bridges on gaged streams, the annual peak discharge data can be used in order to estimate the design discharge. For ungaged sites however, such data is not available and the only possible method is the use of regional flood frequency models that are developed based on estimations of gaged data. The high prediction errors associated with such models along with the fact that climate change and urbanization can also undermine accuracy of the estimated discharges, motivated this research. It was assumed that the most recent available flood prediction model was used by Iowa DOT for determining design discharge at the time of bridge construction. In this regard, the estimated bridge design discharge was compared with the latest estimate of the same flood event. The results showed that as the basins get larger, the estimated discharges are more reliable. It was also concluded that bridges built before 1980s are more prone to experience an increase in their estimated discharges. Floods and resulting scour are responsible for about half of bridge failures in the United States. Catastrophic consequences of bridge failures along with guidelines from the Federal Highway Administration (FHWA) motivated the development of scour assessment tools. HYRISK is one of the available tools for network-level scour analysis and is developed by the FHWA for prioritizing bridges based on their expected scour risk. This study proposed three major modifications to improve and customize HYRISK estimations for Iowa. Soil erodibility was incorporated into the HYRISK along with a modified failure cost calculation accounting for scour countermeasure installation cost rather than bridge reconstruction that was originally being considered. The modified HYRISK was used to estimate the annual cost of scour risk for Iowa DOT bridge network and also the damage to the affected bridges by the 2008 flood in Upper Mississippi River basin. The results were significantly different from original HYRISK estimations and were in line with the actual annual expenditure on scour maintenance program and also the reported damage from the 2008 flood

A Portable RT-LAMP/CRISPR Machine for Rapid COVID-19 Screening.

The COVID-19 pandemic has changed people's lives and has brought society to a sudden standstill, with lockdowns and social distancing as the preferred preventative measures. To lift these measurements and reduce society's burden, developing an easy-to-use, rapid, and portable system to detect SARS-CoV-2 is mandatory. To this end, we developed a portable and semi-automated device for SARS-CoV-2 detection based on reverse transcription loop-mediated isothermal amplification followed by a CRISPR/Cas12a reaction. The device contains a heater element mounted on a printed circuit board, a cooler fan, a proportional integral derivative controller to control the temperature, and designated areas for 0.2 mL Eppendorf® PCR tubes. Our system has a limit of detection of 35 copies of the virus per microliter, which is significant and has the capability of being used in crisis centers, mobile laboratories, remote locations, or airports to diagnose individuals infected with SARS-CoV-2. We believe the current methodology that we have implemented in this article is beneficial for the early screening of infectious diseases, in which fast screening with high accuracy is necessary

Effects of intermittent feeding on compensatory growth, feed intake and body composition in Asian sea bass (Lates calcarifer)

This experiment was conducted to investigate the effects of various starvation and refeeding periods on growth, feed utilization and body composition in Asian sea bass (Lates calcarifer) with an average initial weight of 30.26±1.4 g (mean±SE). The fish were exposed to three different regimes: the control group fed twice daily to apparent satiation throughout the experiment (C), the first group starved for 4 days and refed for 16 days, this cycle was repeated two times (T1) and the second group starved for 8 days and refed for 32 days (T2). At the end of experiment, there were not any significant differences in growth and feeding performance among different treatments (p>0.05). Daily feed intake was significantly higher in the deprived fish than in the control fish (p0.05). Starvation had a significant effect on protein content on one sampling date during the experimental period; protein content in T2 on day 8 was significantly lower compared to the control (p<0.05). Sea bass showed complete compensation indicating a high ability of the deprived fish to grow sufficiently to fully compensate for weight loss during starvation. The results suggested that the feeding schedule involving starvation-refeeding cycles could be a promising feed management option for the culture of this species

Effects of dietary probiotic (Lactobacillus plantarum) on body composition, serum biochemical parameters and liver enzymes of Asian sea bass (Lates calcalifer, Bloch 1790)

In the current study, the effects of different levels of probiotics, Lactobacillus plantarum in the diet of Asian sea bass, Lates calcarifer on body composition, serum biochemical parameters (glucose, cholesterol, triglyceride and albumin) and liver enzymes (lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase) were investigated. This experiment was carried out with three treatments and a control group for a period of four weeks. The treatments were included 0, 1×106, 2×106, 3×106 colony forming unit (CFU) gram probiotic in each gram of basic diet. Fish with an average weight of 50.26 ±0.89 grams were randomly distributed in tanks and in each tank stocked 20 pieces of fish. Feeding was done twice a day. The obtained results indicated that the use of different levels of probiotic in diet of Asian sea bass had no significant effects on serum biochemical parameters and liver enzymes. The different levels of probiotic did not affect protein, ash and moisture values between the treatments and the control group (P> 0.05). Moreover, fat value in the fish T2 and T3 was significantly higher (P< 0.05) than the fish control and T1. Also, nitrogen free extract (NFE) value varied significantly (P < 0/05) between the control and the fish T3. Overall, this study indicated that this probiotic had no significant effect on some blood biochemical parameters and liver enzyme, but at the high level can positively influence on body composition of Asian sea bass

Meta-Analysis of Biofilm Formation, Antibiotic Resistance Pattern, and Biofilm-Related Genes in Pseudomonas aeruginosa Isolated from Clinical Samples

Resistant microorganisms such as Pseudomonas aeruginosa grow by developing biofilms in hospitals. We aimed to investigate the biofilm formation and the frequencies of biofilm-related genes and their associations with antibiotic resistance pattern in P. aeruginosa isolated from Iranians' clinical samples. This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We conducted a systematic literature search in scientific databases using medical subject heading terms, including "Pseudomonas aeruginosa,""biofilm formation,""biofilm-related genes,""antibiotic resistance,"and "prevalence,"to obtain related articles published from 1st January, 2000, to 30th March, 2019. The studies reporting the prevalence of biofilm formation, the frequencies of biofilm-related genes, and the antibiotic resistance pattern in P. aeruginosa retrieved from Iranian patients were included. Meta-analysis was performed using the Comprehensive Meta-Analysis software. The pooled rate of biofilm formation was calculated as 86.5 (95 confidence interval CI: 79-91.6). The combined frequencies of strong, moderate, and weak biofilms were 51% (95% CI: 37.4-64.4), 29.2% (95% CI: 20.9-39.1), and 25.4% (95% CI: 11.5-47.2), respectively. The pooled prevalence of laslR, algD, algU, ppyR, and pelF genes were 93.6% (95% CI: 88.1-96.6), 91.4% (95% CI: 80.8-96.4), 89.3% (95% CI: 85.2-92.3), 98.7% (95% CI: 96.5-99.6), and 93% (95% CI: 82.7-97.3), respectively. The highest combined antibiotic resistance rates of P. aeruginosa isolates were against piperacillin/tazobactam (90%). This study showed that biofilm formation was higher in multidrug-resistant (MDR) P. aeruginosa than non-MDRs. A significant correlation was observed between biofilm formation and antibiotic resistance in 50% of studies included in this review. © Copyright 2020, Mary Ann Liebert, Inc., publishers 2020

Clear-cell carcinoma originating from cesarean section scar: two case reports

Background: Clear-cell carcinoma arising from the surgical cesarean section scar is very infrequent. The present study reports two patients with clear-cell carcinoma arising from an abdominal wall scar 20 and 23 years after their last cesarean section. Case presentation: Both Iranian patients had prior cesarean sections nearly 20 years earlier. Patients 1 and 2 had transverse and vertical abdominal incisions, respectively. The initial clinical presentation was a huge lower abdominal mass at the site of the previous cesarean section scar. Both patients underwent abdominal wall mass biopsy. The histological analysis revealed the presence of malignancy. Both patients underwent full-thickness resection of the abdominal wall mass. All surgical margins were tumor-free; however, patient 1 had a very narrow tumor-free margin near the pubic symphysis. As the imaging report of patient 2 revealed the presence of a pelvic mass, the exploration of the intraperitoneal space, simple total abdominal hysterectomy (TAH), bilateral salpingo-oophorectomy (BSO), and the excision of enlarged pelvic lymph nodes were performed during the surgery. Six cycles of paclitaxel and carboplatin every 3 weeks as adjuvant chemotherapy was administered for both patients after the surgery. One of the patients had disease recurrence 5 months after the termination of chemotherapy, and the other is still disease-free. These two patients had similar pathology and received a similar initial adjuvant treatment; however, they were different in terms of the direction of tumor spread, tumor distance from the pubic symphysis, status of tumor margins, and surgical procedures. Conclusions: We encountered distinct prognoses in the clear-cell carcinoma of cesarean section scars presented herein. The researchers can recommend complete surgical excision of the abdominal wall mass with wide tumor-free margins, exploration of the abdominopelvic space, TAH, and BSO during the first surgery. © 2021, The Author(s)

Out of pocket payment by inpatients after health sector evolution plan and its effecting factors: A report of Iran

Background: The health transformation plan (HTP) was implemented in April 2014 in university hospitals to provide equitable access to healthcare, improve the quality of care, and protect patients against high costs of hospitals. Objectives: The present study aimed to investigate out of pocket (OOP) payment by inpatients after the health sector evolution plan (HSEP) and its effective factors in hospitals affiliated with Iran University of Medical Science. Methods: In this study, descriptive and cross-sectional research design was utilized. 277 patients at 5 hospitals affiliated with Iran University of Medical Sciences were selected via simple random approach. Checklists and hospital bills were used to collect data. Then the data were analyzed by SPSS 19.0. Results: The results indicated that OOP was 18.71 of the total hospitals expenditure. There was a significant relationship among insurance status, location, and OOP (P < 0.05). Conclusions: The OOP rate of hospitalized patients was not in accordance with the goal set in the HSEP. Thus, policymakers and managers should take serious measures to decrease out-of-pocket payments. © 2020, Author(s)

Exceptionally large two- and three-photon absorption cross-sections by OPV organometalation

Oligo(p-phenylenevinylene)s (OPVs) containing up to 8 PV units and end-functionalized by ruthenium alkynyl groups have been prepared and their nonlinear absorption properties assessed using the Z-scan technique and employing low repetition rate femtosecond pulses. Exceptionally large two-photon absorption (ca. 12 500 GM at 725 nm) and three-photon absorption cross sections (ca. 1.6 × 10⁻⁷⁶ cm⁶s² at 1100 nm) are found for the 8PV-containing example, highlighting the potential of an “organometalation” approach to NLO-efficient organic materialsWe thank the Australian Research Council (ARC), the National Natural Science Foundation of China (51432006), the Chinese Government Ministry of Education, the Chinese Government State Administration of Foreign Experts Affairs (111 Project: B13025), and the National Science Centre of Poland (grant 2013/10/A/ST4/00114) for financial support. M. P. C. thanks the ARC for an Australian Research Fellowship and C. Q. thanks CONICYT (Chile) for a Chile PhD Scholarship Abroad