An additional deep-water mass in Drake Passage as revealed by 3He data

We present 3He data froma repeat section across Drake Passage, fromthree sections off the South American continent in the Pacific, at 28?S, 35?S, and 43?S, and fromthree sections in the Atlantic, eastward of the Malvinas, close to 35?W, and near the Greenwich Meridian. In Drake Passage, a distinct high-3He signal is observed that is centered just above the boundary of the Lower and the Upper Circumpolar Deep Water (LCDW, UCDW), and is concentrated towards the northern continental slope. 3He concentrations in the Antarctic Circumpolar Current (ACC) upstream of Drake Passage (World Ocean Circulation Experiment section P19 at 88?W) are markedly lower than those found in Drake Passage, and a regional source of primordial helium in the path of the ACC that might cause the high-3He feature can be ruled out. We explain the feature by addition of high-3He waters present at the 43?S Pacific section. This supports a previous, similar interpretation of a low-salinity anomaly in Drake Passage (Naveira Garabato et al., Deep- Sea Research I 49 (2002) 681), that is strongly related to the high-3He feature. Employing multiparameter water mass analysis (including 3He as a parameter), we find that deep waters as met at the 43?S Pacific section, flowing south along the South American continental slope, contribute substantially to the ACC waters in Drake Passage (fractions exceed 50% locally). Lesser, but laterally more extended contributions are found east of the Malvinas, and still smaller ones are present at 35?W and at the Greenwich Meridian. Using velocity measurements from one of the two Drake Passage sections, we estimate the volume transport of these waters to be 7.071.2 Sv, but the average transport may be somewhat lower as the other realization had a less pronounced signal. The enhanced 3He signature in Drake Passage is essentially confined north of the Polar Front. Further downstreamthe signature crosses this front, to the extent that at 35?W the contributions south and north of it are of similar magnitude. At the same time, the 3He levels north of the front are reduced due to a substantial admixture of low-3He North Atlantic Deep Water, such that 3He becomes highest south of the front. The flow of Southeast Pacific deep slope waters entering the ACC constitutes the predominant exit pathway of the primordial helium released in the deep Pacific, and represents a considerable fraction of the deep water return flow fromthe Pacific into the ACC. Therefore and also because the density range of the added deep slope waters is intermediate between those of UCDW and LCDW, they must be considered a distinct water mass. r 2003 Elsevier Ltd. All rights reserved

Increased Incidence of Congenital Syphilis

Background: Congenital syphilis occurs when a pregnant mother passes the syphilis infection to their child during pregnancy. This treatable sexually transmitted infection (STI) is the leading cause of stillbirths and neonatal deaths (Trivedi et al., 2020). According to the CDC (2021), the incidence of congenital syphilis increased 254% from 2016 to 2020. The key factors include decreased funding for STI education, decreased access to care, limited resources such as transportation and health insurance, stigma that is associated with diagnosis and treatment and legal issues that may be present such as undocumented migrants (Contraceptive Technology Update, 2022). Objective: Increase the education for STI prevention and treatment to decrease the incidence of congenital syphilis. Methods: Through the research design Plan/Do/Study/Act increased education will help to bring awareness of prevention and treatment to women of childbearing ages. Inclusion of community resources such as community centers, rural health clinics, health departments and schools will assist in capturing a more diverse population as well as a greater number of patients. Education will occur as a standard at child appointments, prenatal screenings, during health classes and at community centers. Comparison of congenital syphilis diagnosis from pre- and post- education implementation will provide data to indicate significance. Conclusion: Through implementation of extended education points the healthcare team can reach a greater number of patients and ensure swift and adequate treatment. Syphilis is a treatable infection and when detected and treated in a timely manner will lessen the risk to the unborn child. Utilizing healthcare and community services can provide the necessary education for eliminating poor outcomes for neonates

Population potential in Metropolitan areas

Thesis (M.C.P.) Massachusetts Institute of Technology. Dept. of City and Regional Planning, 1949.Bibliography: leaf 20.by Richard Wellborn Roether.M.C.P

Extensive reuse of soda-lime waste glass in fly ash-based geopolymers

The possibility of extensive incorporation of soda-lime waste glass in the synthesis of fly ash-based geopolymers was investigated. Using waste glass as silica supplier avoids the use of water glass solution as chemical activator. The influence of the addition of waste glass on the microstructure and strength of fly ash-based geopolymers was studied through microstructural and mechanical characterization. Leaching analyses were also carried out. The samples were developed changing the SiO2/Al2O3 molar ratio and the molarity of the sodium hydroxide solution used as alkaline activator. The results suggest that increasing the amount of waste glass as well as increasing the molarity of the solution lead to the formation of zeolite crystalline phases and an improvement of the mechanical strength. Leaching results confirmed that the new geopolymers have the capability to immobilize heavy metal ions

Polyaniline based polymers in tissue engineering applications: a review

A number of electrically conducting polymers, such as polyaniline (PANi), as well as functionalized aniline copolymers and composites, which are simultaneously biodegradable and conductive, have been applied for developing electrically conductive scaffolds for tissue engineering (TE) in recent years. The rationale behind these scaffolds is to induce ‘electroactivity’ in scaffolds, as many research works have shown that an intrinsic electrical activity leads to both increased regeneration rates and improved healing of damaged tissues. PANi is the conductive polymer of choice because it is economical and easy to process with a variety of methods. The resultant PANi based biomaterials have shown biocompatibility, conductivity, suitable processability, positive cellular response, as well as an intrinsic antibacterial effect in numerous research studies. The analysis of the literature has revealed that PANi based scaffolds have been investigated for TE applications including skin/wound healing, bone, cartilage, nerve/spinal cord, vascular, skeletal muscle repair and for the treatment of infertility. Although PANi based materials find widespread applications in other sectors, they are still far away from being commercially exploited as scaffolds for TE despite positive research results. This review aims to discuss and critically assess the current state of PANi based TE scaffolds for different applications. A future perspective for utilizing PANi based biomaterials for applications in TE is discussed, including recent considerations about potential cytotoxic effects

Changes in ventilation of the Mediterranean Sea during the past 25 year

Significant changes in the overturning circulation of the Mediterranean Sea has been observed during the last few decades, the most prominent phenomena being the Eastern Mediterranean Transient (EMT) in the early 1990s and the Western Mediterranean Transition (WMT) during the mid-2000s. During both of these events unusually large amounts of deep water were formed, and in the case of the EMT, the deep water formation area shifted from the Adriatic to the Aegean Sea. Here we synthesize a unique collection of transient tracer (CFC-12, SF6 and tritium) data from nine cruises conducted between 1987 and 2011 and use these data to determine temporal variability of Mediterranean ventilation. We also discuss biases and technical problems with transient tracer-based ages arising from their different input histories over time; particularly in the case of time-dependent ventilation. We observe a period of low ventilation in the deep eastern (Levantine) basin after it was ventilated by the EMT so that the age of the deep water is increasing with time. In the Ionian Sea, on the other hand, we see evidence of increased ventilation after year 2001, indicating the restarted deep water formation in the Adriatic Sea. This is also reflected in the increasing age of the Cretan Sea deep water and decreasing age of Adriatic Sea deep water since the end of the 1980s. In the western Mediterranean deep basin we see the massive input of recently ventilated waters during the WMT. This signal is not yet apparent in the Tyrrhenian Sea, where the ventilation seems to be fairly constant since the EMT. Also the western Alboran Sea does not show any temporal trends in ventilation

Functional Analysis of the RNA Polymerase II C-terminal Domain Kinase Ctk1 in the Yeast Saccharomyces cerevisiae

Gene expression encompasses a multitude of different steps, starting with transcription in the nucleus, co-transcriptional processing and packaging of the mRNA into a mature mRNP, export of the mRNP through the nuclear pore and finally the translation of the message in the cytoplasm. The central coordinator for coupling of the nuclear events is the differentially phosphorylated C-terminal domain (CTD) of RNA polymerase II (RNAP II). The phosphorylation pattern of the CTD not only dictates the progression through the transcription cycle but also the recruitment of mRNA processing machineries. Coupling of transcription to mRNA export is achieved by the TREX complex, which consists in the yeast S. cerevisiae of the heterotetrameric THO complex important for transcription elongation, the SR-like proteins Gbp2 and Hrb1, and Tex1 and the mRNA export factors Sub2 and Yra1. By direct interaction with Yra1, the mRNA export receptor Mex67-Mtr2 is then recruited to the mRNP and transports the mRNP through the nuclear pore complex to the cytoplasm. In a genetic screen for factors that are crucial for TREX complex function in the living cell, Ctk1, a cyclin dependent kinase (CDK) that phosphorylates the C-terminal domain (CTD) of RNAP II during transcription elongation, was identified (Hurt et al. 2004). Surprisingly, besides the TREX components Gbp2 and Hrb1, Ctk1 co-purified ribosomal proteins and translation factors. Using sucrose density centrifugation, it could be shown that Ctk1 indeed associates with translating ribosomes in vivo, suggesting a novel function of this protein in translation. This assumption was confirmed by in vitro translation assays: loss of Ctk1 function leads to a reduction in translational activity. More specifically, Ctk1 is important for efficient translation elongation and contributes to the accurate decoding of the message. Cells depleted for Ctk1 are more sensitive towards drugs that impair translational accuracy and show an increase in the frequency of miscoding in vivo. The function of Ctk1 during decoding of the message is most likely direct, as in extracts of cells depleted for Ctk1 the defect in correct decoding of the message can be restored to wild type levels by addition of purified CTDK-I complex. An explanation for the molecular mechanism of Ctk1’s function is provided by the identification of Rps2 as a novel substrate of Ctk1. Rps2 is a protein of the small ribosomal subunit, located at the mRNA entry tunnel and known to be essential for translational accuracy. Importantly, Rps2 is phosphorylated on serine 238 by Ctk1, and cells containing an rps2-S238A mutation show an increased sensitivity towards drugs that affect translational accuracy and an increase in miscoding as determined by in vitro translation extracts. The role of Ctk1 in translation is probably conserved as CDK9, the mammalian homologue of Ctk1, also associates with polysomes. Since Ctk1 interacts with the TREX complex, which functions at the interface of transcription and mRNA export, Ctk1 might bind to the mRNP during transcription and accompany the mRNP to the ribosomes, where Ctk1 enhances efficient and accurate translation of the mRNA. This study could be an example of a novel layer of control in gene expression: the composition of the mRNP determines its translational fate, including efficiency and accuracy of translation

Interbasin deep water exchange in the western Mediterranean

Owing to its nearly enclosed nature, the Tyrrhenian Sea at first sight is expected to have a small impact on the distribution and characteristics of water masses in the other basins of the western Mediterranean, The first evidence that the Tyrrhenian Sea might, in fact, play an important role in the deep and intermediate water circulation of the entire western Mediterranean was put forward by Hopkins [1988]. There, an outflow of water from the Tyrrhenian Sea into the Algero Provencal Basin was postulated in the depth range 700-1000 m, to compensate for an observed inflow of deeper water into the Tyrrhenian Sea. However, this outflow, the Tyrrhenian Deep Water (TDW), was undetectable since it would have hydrographic characteristics that could also be produced within the Algero-Provencal Basin. A new data set of hydrographic, tracer, lowered Acoustic Doppler Current Profiler (LADCP), and deep float observations presented here allows us now to identify and track the TDW in the Algero-Provencal Basin and to demonstrate the presence and huge extent of this water mass throughout the western Mediterranean. It extends from 600 m to 1600-1900 m depth and thus occupies much of the deep water regime. The outflow from the Tyrrhenian is estimated to be of the order of 0.4 Sv (Sv=10(6) m(3) s(-1)), based on the tracer balances. This transport has the same order of magnitude as the deep water formation rate in the Gulf of Lions. The Tyrrhenian Sea effectively removes convectively generated deep water (Western Mediterranean Deep Water (WMDW)) from the Algero-Provencal Basin, mixes it with Levantine Intermediate water (LIW) above, and reinjects the product into the Algero-Provencal Basin at a level between the WMDW and LIW, thus smoothing the temperature and salinity gradients between these water masses. The tracer characteristics of the TDW and the lowered ADCP and deep float observations document the expected but weak cyclonic circulation and larger flows in a vigorous eddy regime in the basin interio