Low Figure Research Articles

Design and implementation of a broad-band high gain low noise amplifier for 3G/4G applications

The main aim of the paper is designing and implementing a broadband low-noise-amplifier (LNA) based on compensated matching network techniquein order to get high stable gain, low noise figure, low cost and smaller sizefor 3G/4G communication system applications at 2 GHz with bandwidth 600MHz. The Advanced Design System simulates the proposed circuit (ADS).The implementation was done with a class A bias circuit and a low noise transistor BFU 730F with a lower Noise Figure (NFmin) 0.62 dB. Collectorcurrent is measured to be 5.8mA and base current is 19.1μA with a supply voltage of 2.25V. The new design proposed a (NFmin) of 0.62 dB with a 17.8dB high stable amplifier gain. The microstrip lines (MSL) and compensated matching network techniques were used to improve the LNA’s stability and achieve a good result. The LNA board is implemented and assembled on the FR4 botton layer material. The results are virtually non existence equivalent between the simulated and the measured results.

Study of BC14N-bilayer graphene: Effects of atomic spacing and interatomic interaction between B and N atoms

We study the effects of an attractive interaction between the boron (B) and the nitrogen (N) atoms doped in a bilayer graphene (BLG), BC 14 N, on the electronic, the thermal and the optical properties for two different types of a doping process: First, both the B and the N atoms are doped in the same layer while the other layer is undoped. Second, the B and N atoms are doped in both layers. An attractive interaction between the B and N atoms does not influence the interlayer interaction in the first case, while it does in the second case. We find that the strong B-N attractive interaction in one layer induces metallic behavior due to the crossing of the valence band and the Fermi energy, while the strong attractive interaction between both layers induces a semiconductor property arising from the emergence a bandgap. We therefore confirm that the metallic-like BLG is not a good material for thermal devices because it has a low figure of merit, while we notice that the semiconductor-like BLG has a high Seebeck coefficient and figure of merit as well as a low thermal conductivity . The strong attractive interaction of the B-N atoms between the layers gives rise to a prominent peak to appear in dielectric function, the excitation and the absorption spectra in the low energy, visible range, while a very weak peak is seen in the case of a strong attractive interaction between the B and N doped in one layer. Last, the ferromagnetic and anti-ferromagnetic phases of the BN-codoped structures are also discussed. Controlling the B and N atomic configurations in the BLG may help to improve the material for use in both thermoelectric and optoelectronic devices . • Attractive interaction between BN dopant atoms decreases interlayer spacing of BLG. • Attractive interaction induce a pronounced bandgap. • Dielectric function, the excitation and the absorption spectra in the low energy, visible range, are enhanced. • Thermoelectric efficiency is enhanced due to presence of attractive interaction.

How many men work in the English early years sector? Why is the low figure so ‘stubbornly resistant to change’?

AbstractThis study draws on data from the GenderEYE project, research conducted in England between 2018 and 2020, which aimed to examine the recruitment, support and retention of male teachers within early years education (EYE) with a view of developing a more gender diverse workforce in this sector. Data collection was by means of a survey, 9 case studies with early years settings and interviews with key stakeholders. In this study, we examine a key finding about the persistently low numbers of male EYE professionals, linking this to another finding concerning a lack of specific strategy to recruit and support men.

Prospective study of the incidence density of multi-resistant microorganisms and Clostridioides difficile during the period 2012- 2019 in the Canary Islands

RESUMENIntroducciónEl Servicio Canario de Salud implementó a partir de 2012 un nuevo sistema de vigilancia de infecciones nosocomiales causadas por microorganismos multirresistentes y Clostridioides difficile. Este sistema permitirá conocer las tasas de incidencia de estos patógenos, contrastarlas periódicamente para vigilar su tendencia y compararlas con las de otras instituciones sanitarias nacionales y europeas.Pacientes y métodoEstudio observacional, prospectivo de la densidad de incidencia de patógenos multirresistentes y Clostridioides difficile en los centros sanitarios del Servicio Canario de la Salud desde 2012 hasta 2019.ResultadosLa densidad de incidencia de infecciones por Staphylococcus aureus resistente a meticilina para el año 2012 fue de 1,96 casos por 10.000 estancias y disminuyó a 0,80 en 2019, alcanzando la cifra más baja en el periodo de vigilancia. Las infecciones por enterobacterias productoras de carbapenemasas mostraron una tendencia ascendente, 0,47 (2014) y 2,35 (2019). Se ha corregido la ligera tendencia al alza de infecciones por Acinetobacter baumannii resistente a imipenem en las bacteriemias observadas 0,17 (2012) y 0,09 (2019). No se observaron casos de infección por enterococos resistentes a vancomicina. En cuanto a C. difficile, se ha consolidado una tendencia al alza que inició en 2012, produciéndose un incremento de un 216% en el número de casos detectados al final del periodo de estudio.ConclusiónEl problema más importante detectado en la actualidad son las enterobacterias productoras de carbapenemasas. Los datos analizados en este período muestran un cambio evidente en la tendencia de los patógenos multirresistentes estudiados. Este hecho debe confirmarse en el futuro.

Prevalence of Myopia in America

In recent years, prevalence of myopia in the world has increased significantly. The aim of this research work is to consider the combined prevalence of myopia in America, according to the following categories: age, race, gender, and region. Such research will be done also in harmony with the reports found in scientific literature. A systematic review of the literature found in the following databases was carried out: medline, embase, and lilacs. The aim was searching cross-sectional studies containing myopia prevalence information. To find the combined prevalence, the double arc sine method of fixed or random effects by Freeman-Tukey was used. 15 research studies that included 45.349 individuals from the United States, Brazil, and Paraguay, were identified in the literature; studies of subjects aged 0-96 years old. The prevalence of myopia varied from 1,2% to 48% with differences between male and female of 18,4% [95% CI: 13,9-22,8] and 19,8% [95% CI: 18,9-20,7], respectively. The global prevalence of myopia in rural areas was 1,4% [95% CI: 1,3-1,5], and in urban areas 14,3% [95% CI: 13,3-15,2]. At the same time, some differences were identified based on race. In the case of the white race 15,4% [95% CI: 14,4-16,3], Afrodescendants 20,6% [95% CI: 19,6-21,5] and other races (Spanish, non-Spanish, and African American) 2,9% [95% CI: 1,97-3,82]. The lowest figures of myopia prevalence were identified in rural areas in pre-school children (14,1%). There is, probably, a relationship in use and exposure time to electronic items such as screens, in contrast with the development of other indoor activities as outdoor exposure as an environmental factor to slow myopia.

CMOS Realizable and Highly Cascadable Structures of First-Order All-Pass Filters

Two novel resistorless structures of a first-order voltage-mode all-pass filter are presented in the paper. Both the structures employ a fully differential second-generation current conveyor (FDCCII) as the primary active element, in addition to an active resistor. A grounded capacitor is the only passive component used in both the structures. In both the structures, CMOS realization of FDCCII is utilized; hence, these structures are CMOS compatible. Some of the other highly demanded features possessed by the presented all-pass structures are: a simple circuit topology, electronic tunability, high input impedance, constraint-free operation in terms of passive component matching, and low sensitivity figures. The theoretical performances under ideal and non-ideal scenarios are presented in detail. Furthermore, the proposed idea is extended to an Nth-order voltage-mode all-pass filter and a quadrature oscillator to explore some of the possible applications. PSPICE simulation results verify the theoretical claims of the presented all-pass filters.
 HIGHLIGHTS
 
 Two novel resistorless structures of first-order all-pass filters based on fully differential second-generation current conveyor are presented
 Performance of the proposed structures are thoroughly described in ideal and non-ideal scenarios
 Theoretically described details of the proposed structures are verified by carrying simulations on PSPICE using 180 nm CMOS technology
 An Nth-order all-pass filter and a quadrature oscillator are also presented as applications
 
 GRAPHICAL ABSTRACT

COVID-19 pandemic in BRICS countries and its association with socio-economic and demographic characteristics, health vulnerability, resources, and policy response

BackgroundLittle attention has been paid to the comparison of COVID-19 pandemic responses and related factors in BRICS (Brazil, Russia, India, China, and South Africa) countries. We aimed at evaluating the association of daily new COVID-19 cases with socio-economic and demographic factors, health vulnerability, resources, and policy response in BRICS countries.MethodsWe conducted a cross-sectional study using data on the COVID-19 pandemic and other indicators of BRICS countries from February 26, 2020 to April 30, 2021. We compared COVID-19 epidemic in BRICS countries and analyzed related factors by log-linear Generalized Additive Model (GAM) models.ResultsIn BRICS countries, India had the highest totally of confirmed cases with 18.76 million, followed by Brazil (14.45 million), Russia (4.81 million), and South Africa (1.58 million), while China (0.10 million) had the lowest figure. South Africa had the lowest rate of administered vaccine doses (0.18 million) among BRICS countries as of April 30, 2021. In the GAM model, a 1 unit increase in population density and policy stringency index was associated with a 5.17% and 1.95% growth in daily new COVID-19 cases (P < 0.001), respectively. Exposure–response curves for the effects of policy stringency index on daily new cases showed that there was a rapid surge in number of daily new COVID-19 cases when the index ranged from 0 to 45. The number of infections climbed slowly when the index ranged from 46 to 80, and decreased when the index was above 80 (P < 0.001). In addition, daily new COVID-19 cases (all P < 0.001) were also correlated with life expectancy at birth (-1.61%), extreme poverty (8.95%), human development index (-0.05%), GDP per capita (-0.18%), diabetes prevalence (0.66%), proportion of population aged 60 and above (2.23%), hospital beds per thousand people (-0.08%), proportion of people with access to improved drinking water (-7.40%), prevalence of open defecation (0.69%), and annual tourist/visitor arrivals (0.003%), after controlling other confounders. Different lag structures showed similar results in the sensitivity analysis.ConclusionsStrong policy response is crucial to control the pandemic, such as effective containment and case management. Our findings also highlighted the importance of reducing socio-economic inequalities and strengthening the resilience of health systems to better respond to public health emergencies globally.Graphic abstract

Enhanced physical characteristics of ZnO thin films through Sr and Mg co-doping

ABSTRACT In this study, undoped ZnO, (Sr, Mg) co-doped ZnO (SMZO) thin films were synthetised on heated glass substrates at a temperature of 250°C by using ultrasonic spray technique. Doping strontium (Sr) and magnesium (Mg) into zinc oxide (ZnO) offers an important way to modify various properties. X-ray diffraction (XRD) confirmed that the films exhibited the hexagonal wurtzite structure of ZnO with a favored orientation along (002) plane . Scanning electron microscope (SEM) showed a strong change in the surface morphology while Energy dispersive X-ray spectrometer (EDX) and mapping confirmed the purity of the films . UV-Visible studies demonstrated that the optical transmittance was improved to an average value above 94% and that Mg-doping induces an increase of the band gap indicating high optical quality of the films. From the fabricated films, SMZO3 is the most appropriate for optoelectronic applications where a low resistivity and high figure of merit were obtained.

Enhanced thermoelectric performance and mechanical strength of n-type BiTeSe materials produced via a composite strategy

Zone-melted Bi2Te2.7Se0.3 (ZM BTS) alloys are typical n-type commercial thermoelectric (TE) materials and are utilized for refrigeration and power generation near room temperature. They usually suffer from poor mechanical performance, as well as having a low figure of merit (ZT). In this work, we report an effective composite strategy to improve both the TE and mechanical performance of n-type BTS materials by incorporating carbon microfibers. The introduction of carbon microfibers in BTS effectively reduces the lattice thermal conductivity due to phonon scattering at multi-scale boundaries and due to the large interfacial thermal resistance arising from phonon mismatch between the constituent phases. Simultaneously, it also gives rise to an enhancement of the electrical conductivity, which originates from the increased carrier density without significant limitation on its weighted mobility. Consequently, a high peak ZT of 1.1 at 400 K and an average ZTave value of 0.95 are achieved in the temperature range 300 ~ 550 K, yielding a calculated efficiency of η = 9%. Moreover, the BTS/carbon microfiber composites show superior compressive strength compared to a commercial ZM BTS sample. This improved strength is highly desirable for real-world TE applications. Our results demonstrate a novel way to produce high-performance TE materials, in which interfaces with large thermal resistance are used to achieve low thermal conductivity without significantly degrading the electrical properties of the materials.

New population estimate for an abundant marine indicator species, Rako or Buller’s Shearwater (Ardenna bulleri)

ABSTRACT Accurate and repeatable population estimates are key to establishing population trends and conservation status. Rako, or Buller’s Shearwater (Ardenna bulleri) is a seabird endemic to New Zealand that breeds only on the Poor Knights Islands, but forages throughout wider areas of the Pacific Ocean during the non-breeding season. The lack of threats on the breeding grounds and the wide foraging range of Buller’s Shearwaters makes them ideal sentinels of ocean health. Although they are commonly seen at sea and the population in the 1980s was thought to be around 2.5 million birds, other rapid land-based surveys suggested a much lower figure (~100,000 pairs on Aorangi), and no thorough population estimate has been undertaken to date. We calculated a population estimate for Buller’s Shearwater based on burrow counts and state of occupancy conducted at the Poor Knights during either the 2016–2017 or the 2017–2018 breeding seasons. We incorporated information on habitat availability and preference in population models. Our estimate of 78,645 (95% confidence interval 67,176–89,178) active burrows, broadly representing breeding pairs, is lower than some previously published assessments. This is a repeatable quantitative study of the Buller’s Shearwater breeding population, including breeding activity, and provides critical baseline data to determine population trends for this potentially important marine indicator species.

High Performance of a Metal Layer-Assisted Guided-Mode Resonance Biosensor Modulated by Double-Grating.

Guided-mode resonance (GMR) sensors are widely used as biosensors with the advantages of simple structure, easy detection schemes, high efficiency, and narrow linewidth. However, their applications are limited by their relatively low sensitivity (<200 nm/RIU) and in turn low figure of merit (FOM, <100 1/RIU). Many efforts have been made to enhance the sensitivity or FOM, separately. To enhance the sensitivity and FOM simultaneously for more sensitive sensing, we proposed a metal layer-assisted double-grating (MADG) structure with the evanescent field extending to the sensing region enabled by the metal reflector layer underneath the double-grating. The influence of structural parameters was systematically investigated. Bulk sensitivity of 550.0 nm/RIU and FOM of 1571.4 1/RIU were obtained after numerical optimization. Compared with a single-grating structure, the surface sensitivity of the double-grating structure for protein adsorption increases by a factor of 2.4 times. The as-proposed MADG has a great potential to be a biosensor with high sensitivity and high accuracy.

Effects of Seasonal Variation on Performance of Conventional Wastewater Treatment System

The study was to determine the seasonal differences of conventional wastewater treatment process. This was done by sampling and analyses of wastewater samples from four different points during the dry and wet seasons of the year 2019. Water samples were taken from influent point, primary effluent, trickling filter effluent and final effluent. Gravimetric method was used in determining Total Suspended Solids (TSS) and Total Dissolved Solids (TDS). The BOD 5 technique was used for determination of Biological Oxygen Demand (BOD) and the digestion method was used for determination Chemical Oxygen Demand (COD). Temperature, pH and conductivity were measured using respective meters. Analysis of Variance showed that there was significant difference (p &lt; 0.05) in all the parameters quantified at all the points of treatment during the two seasons. The results showed that BOD and COD both reduced from one point to the next during the two seasons of study. The TSS levels increased after primary pond effluent undergoing treatment at the trickling filter and the temperature also increased after the trickling filter effluent undergoing treatment at oxidation ponds. The levels of conductivity and TDS decreased from one treatment stage to the next during dry season but during the wet season the levels of these parameters increased from one stage to the next except that the levels reduced after the primary pond effluent underwent treatment at the trickling filter. The various stages of wastewater treatment plant under were effective during the two seasons however, wet season recorded lower figures for most of the parameters. Keywords: effluent, influent, wastewater, seasonal variation, ponds DOI: 10.7176/JEES/11-7-06 Publication date: July 31 st 2021

Development of Foam-Based 3-Dimensional Culture to Investigate Drug Sensitivity in Primary Leukaemia Cells

IntroductionDevelopment of assays for evaluating leukaemia cells' sensitivity to antileukaemia agents is emerging to be an important aspect of personalized medicine. The conventional cell cultures lack the three-dimensional (3D) structure of the bone marrow (BM), the extracellular matrix and stromal components which are crucial for the growth and survival of leukaemia stem cells. To accurately predict the sensitivity of the leukaemia cells in an in vitro assay a culturing system containing the essential components of bone marrow is required. Various 3D cultures have been developed so far for studying leukaemia cells (Aljitawi et al . 2014). We hypothesize that a scaffold containing the spongious structure of the BM by providing the niche like spaces recapitulates the resistance to targeted therapy observed in a subset of leukaemia cells in vivo .Materials & MethodsA V-junction microfluidic device was used for bubble preparation. Calcium alginate foam-based scaffold were produced using sodium alginate solution (Ahmad et al. 2011) followed by adding Hydroxyapatite. Alginate microbubbles were collected in calcium chloride to cross-link the bubbles' shell. K562, AR230 and HL60 cell lines were cultured in RPMI medium supplemented with FBS, L-glutamine and penicillin/streptomycin. Cell proliferation and viability was measured by MTS assay. Primary normal CD34+ and acute myeloid leukaemia cells were cultured in StemSpan medium supplemented with CC100. Immunophenotype was determined using 8-color Euroflow AML/MDS antibody panel (CD16 FITC, CD13 PE, CD34 PerCP-Cy5.5, CD117 PE-Cy7, CD11b APC, CD10 APC-H7, HLA-DR V450, CD45 V500) for investigation of myeloid differentiation in normal CD34+ cells and myeloblasts from two AML patients. Data was acquired in a FACSCanto II flow cytometer (BD) and analysed with Infinicyt software (Cytognos).Results and conclusionK562 and HL60 leukemia cell lines were cultured in the porous alginate foam-based scaffold (Scanning Electron Microscopy image, top left figure) followed by evaluating their sensitivity to antileukaemia agents through measuring cell proliferation. Similar to BM niches, micro-cavities in the scaffold accommodated leukaemia cells (top right figure). Foam-based scaffold reduced the sensitivity of K562 and HL60 cells to inhibitory effect of imatinib and doxorubicin respectively compared to 2D culture (low left and right figures). Combination of foam-based scaffold with BM-derived stromal HS-5 cell line further reduced the leukaemia cells' sensitivity to antileukaemia agents. Foam-based 3D culture increased the differentiation of the haematopoietic cells compared to 2D culture as normal CD34+ precursors in the scaffold showed stronger and more homogenous expression of the myeloid associated antigens CD117 and CD13. Similarly, myeloblasts from AML patients in foam-based 3D culture showed a profound monocytic differentiation compared to 2D culture after 3 days. Similar to cell lines, primary CML CD34+ and primary AML blast cells showed increased resistance to imatinib and doxorubicin respectively in foam-based 3D compared to 2D culture (Figure). The conventional 2D culture is not a highly reliable system for drug sensitivity investigations as the in vitro drug sensitivity of leukaemia cells in 2D culture is different from what is observed in vivo (Edmondson et al . 2014). Our foam-based 3D culture reduced the leukaemia cells' sensitivity to antileukaemia agents and further induced the differentiation of the normal and leukaemia cells compared to 2D culture. These differences might be attributed to microcavities mimicking bone marrow niches in foam-based scaffold. We propose to apply this foam-based 3D culture for drug sensitivity investigations and therapeutic target discoveries. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

American Unemployment: Past, Present, and Future

One can scarcely imagine a more timely and thought-provoking volume than Stricker’s survey of American unemployment, its stubborn persistence, and its menacing prospects. When Stricker sent his book to press, he could not have foreseen that two months before its publication COVID-19 would trigger a massive surge of unemployment to levels not seen since the Great Depression. Yet this book seems to have anticipated the circumstances in which we now find ourselves, and Stricker’s scholarship prepares us well to understand one of the most pressing problems with which we will likely struggle as a result of the pandemic—persisting unemployment—by setting that problem in deep historical perspective.The book is organized in two parts. Part I draws upon both history and economics to provide an overview of U.S. unemployment from the panic and depression of 1873 through 2018 and the Trump administration’s early years. That history is replete with the erroneous, unfounded, yet enduring assumptions of employers and elites that the unemployed bear a large share of the blame for their unemployment; that many, if not most of them, would shirk work if they could; that we need unemployment to keep inflation in check; and that the quest for full employment is at best a pipe dream and at worst a recipe for economic calamity. Over time, those in power have consistently clung to such beliefs even when the facts repeatedly contradicted them. Just as late nineteenth-century elites denied the reality of “involuntary unemployment” (17)—even as their cities filled with jobless people during the depressions of the 1870s and 1890s—late twentieth-century economists kept insisting that efforts to achieve full employment would transgress their fabricated Maginot line—the Non-Accelerating Inflation Rate of Unemployment (nairu)—and trigger explosive, growth-destroying inflation. They clung to that flawed theory even as contradictory evidence mounted and record low unemployment figures were reached just prior to the COVID-19 pandemic with little to no inflationary impact.Two aspects of this historical survey stand out. One is policymakers’ apparent ambivalence about accurately measuring unemployment. Stricker informs us that the first attempt to take accurate measurements of unemployment in the United States during the 1930s and 1940s followed more than a half-century of experience with bouts of mass unemployment. For a time, these early figures seemed reliable. Since the 1970s, however, standard measures appear consistently to understate unemployment, with no hint of a revision in the works as yet. The rationale seems to be that what is unknown cannot do any political harm.A second outstanding feature of Stricker’s treatment is his analysis of the huge ideological, economic, and policy reorientation that took place between 1975 and 2000, which he pithily summarizes as “a shift from the War on Poverty to the War on the Poor” (87). The ideas of neoliberal economist Milton Freidman, the monetary policies of Federal Reserve chair Alan Greenspan, and the compromises forged by business-oriented Democrats with free-market Republicans produced a policy consensus that rejected government intervention in the economy as a means of promoting full employment. Yet, while twenty-first-century policymakers apparently gave up on full employment as a worthy aspiration, the Obama–Trump recovery from 2011 to 2019 brought us closer to that goal than at any point since World War II, all without triggering the inflation that the nairu mavens had long predicted.Part II of this book steps out of history to discuss debates about the measurement of unemployment and to ask why the world’s strongest and most developed economy has suffered so much unemployment and what it might finally do to achieve full employment. Particularly pertinent in his concluding chapter is Stricker’s insistence that Americans can afford a massive jobs program. In the past, it was “not lack of money but class interests and political opportunism” that blocked such a program (187). These words are worth remembering as we contemplate how to create a good-jobs-generating economy that can rebuild the nation in response to COVID-19. We owe Stricker a debt of gratitude for this well-crafted and timely work.

Consumers' knowledge and perceptions of endangered livestock breeds: How wording influences conservation efforts

Although consumer demand plays a key role in the conservation of endangered livestock breeds (also referred to as old, local, rare or heritage breeds), consumer research so far has made only a minor contribution to such conservation. Based on a qualitative consumer study using think-aloud-protocols, this article sheds light on consumers' knowledge and perceptions regarding endangered livestock breeds and provides recommendations to improve product communication. The findings include that only half of the participants were aware of the endangerment of livestock breed diversity. While brochures used as stimuli succeeded to motivate the informed participants to support breed conservation through their consumption, the uninformed participants exhibited difficulties in understanding the concept of endangered farm animal breeds. Many misattributed the cause of endangerment to consumer demand for the products of these breeds, influenced by a false analogy with wildlife extinction. These participants objected to the idea of consuming products from any endangered animal and thus were unwilling to support the conservation of rare farm animal breeds through their consumption behaviour. As a result, neither the endangerment nor their currently low population figures should be presented in consumer communication. To support product sales, the exceptional taste of these heritage breeds should be emphasised.

High-resolution esophageal manometry in patients with achalasia

Introduction. At present, high-resolution esophageal manometry is the «gold standard» for the diagnosis of esophageal achalasia, based on the determination of the integrated relaxation pressure of the lower esophageal sphincter, the value of which in the case of achalasia must exceed 15 mm Hg (MMS System). However, in some patients with clinically and radiologically confirmed achalasia, this value is normal. There is no unified view of the cause of this phenomenon. We assumed that low pressure figures may be affected by incorrect installation of the manometric catheter.Methods and materials. This research included 149 patients (61 by retrospective estimating the patients data and 88 new patients) with achalasia established during the period from January 2017 to March 2020. When it was impossible to localize the lower esophageal sphincter and take correct measurements during high-resolution manometry in new patients, the X-rays or upper endoscopy was performed to control the manometric catheter placement. If its’ placement was incorrect and the integrated relaxation pressure level was lower than 15 mmHg, repeated high-resolution manometry was performed with the over-the-guidewire manometric catheter placing.Results. In 36 patients of both groups (24.2 %), the manometric data did not correspond to esophageal achalasia; in the prospective group, 12 out of the 19 patients had incorrect manometric data due to inability to visualize lower esophageal sphincter. In the prospective group, the manometric catheter was reinstalled by a guidewire, which allowed visualizing the signs of the lower esophageal sphincter in all cases, and in 15 out of 19 patients (79 %), the integrated relaxation pressure of the lower esophageal sphincter was more than 15 mm Hg.Conclusions. In some cases, the over-the-guidewire installing makes it possible to pass catheter through the lower esophageal sphincter correctly, visualize the lower esophageal sphincter during the high-resolution manometry examination and obtain true pressure values.

PRODUCTIVITY FORMATION OF MEADOW CLOVER DEPENDING ON INTENSIFICATION FACTORS

In the first year of life of meadow clover, except for uncovered sowing also carry out sowing under the cover of oatmeal mixture for green forage and spring barley on grain. It was noted that for the period of slanting ripeness of the harvest of leaf masses the oatmeal mixture was 24.8 t / ha without fertilizer with an output of 2.7 t / ha of feed units, on the variant with the addition of P 60 K 90 - 36.4 t / ha and 3.9 t / ha, respectively, while for foliar feeding micro-fertilizers "Quantum Beans" - 38.2 t / ha and 4.1 t / ha respectively. The maximum yield of meadow clover dry matter in the first year of life was noted when applying mineral fertilizers in a dose of P 60 K 90 and performing foliar feeding with Quantum Beans. Thus, in the variant without a cover it was 6.5 t / ha, in the variant with a cover is ovs - 3.5 t / ha, with a cover barley yarn - 3.2 t / ha. In the second year of the meadow clover's life two full crops of leaf-steel mass were received. It was noted that the productivity of the herbage was high in uncovered crops. Thus, in the option without fertilizers yielded 23.9 tons / ha, with the application of potassium phosphate fertilizers - 32.2 tons / ha. When applying foliar fertilizer on the potassium phosphate background, the yield was 36.4 t/ha. The high dry solids yield was distinguished by the application of potash and phosphate fertilizers and rootless chelate treatment. Under these conditions, 6.9 tons per hectare of dry matter were obtained from coverless crops. A slightly lower figure was obtained in the undercut variants. Thus, after the cover of oatmeal mixture was formed 6.7 t / ha of dry matter, and after spring barley on grain - 6.4 t / ha. In total for two years of vegetation of meadow clover, in versions without cover, the yield of digestible protein was within 1.17-1.71 tons / ha, feed units - 9.20-13.54 tons / ha, feed units - 10 46-15.32 tons / ha.

Boosting the thermoelectric performance of n-type Bi2S3 by hierarchical structure manipulation and carrier density optimization

Te-free Bi 2 S 3 -based thermoelectric materials show great potential for eco-friendly and industrial scale-up applications because of their high-abundance, low-cost, low-toxicity, and low-thermal-conductivity features. However, their low figure of merit, ZT limits their further applications. In this work, we report a high ZT of ~0.8 at ~760 K in n-type polycrystalline Bi 2 S 3 by a combination of hierarchical structure manipulation and carrier density optimization. A step-by-step fabrication by using mechanical alloying, high-pressure and high-temperature treatment, spark plasma sintering, and annealing leads to unique micro/nanostructures in polycrystalline Bi 2 S 3 including refined grains, high-density Bi-rich nanoprecipitates, significant lattice distortions, and nanopores that confirmed by comprehensive characterizations, which contribute to significantly suppressed lattice thermal conductivity of 0.41 W m −1 K −1 at ~760 K. A further 0.5 mol% CuCl 2 -doping triggers impurity band in the electronic structure of Bi 2 S 3 and narrows the bandgap for optimizing the carrier concentration at ~1 × 10 20 cm −3 , confirmed by both experimental results and first-principles density functional theory calculations. The optimized carrier concentration and maintained low lattice thermal conductivity give rise to a high power factor of ~5.3 μW cm −1 K −2 and high ZT that ranks as a top value. This work provides a new route to achieve high thermoelectric performance in n-type polycrystalline Bi 2 S 3 . • A record-high ZT of ~0.8 at 760 K is achieved in n-type polycrystalline Bi 2 S 3 . • CuCl 2 -doping triggers impurity band of Bi 2 S 3 and narrows its bandgap. • An optimized n e of ~1 × 10 20 cm −3 leads to a high S 2 σ of ~5.3 μW cm −1 K −2 at 760 K. • Unique micro/nanostructures significantly suppress κ l to 0.41 W m −1 K −1 at 760 K.

Chronic obstructive pulmonary disease and lung cancer: access to palliative care, emergency room visits and hospital deaths

BackgroundDespite the severe symptoms experienced by dying COPD patients, specialized palliative care (SPC) services focus mainly on cancer patients. We aimed to study the access to SPC that COPD and lung cancer (LC) patients receive and how that access affects the need for acute hospital care.MethodsA descriptive regional registry study using data acquired through VAL, the Stockholm Regional Council’s central data warehouse, which covers nearly all healthcare use in the county of Stockholm. All the patients who died of COPD or LC from 2015 to 2019 were included. T-tests, chi-2 tests, and univariable and multivariable logistic regression analyses were performed on the accumulated data.ResultsIn total, 6479 patients, (2917 with COPD and 3562 with LC) were studied. The patients with LC had more access to SPC during the last three months of life than did those with COPD (77% vs. 18%, respectively; p < .0001), whereas patients with COPD were more likely to be residents of nursing homes than those with LC (32% vs. 9%, respectively; p < .0001). Higher socioeconomic status (SES) (p < .01) and patient age < 80 years (p < .001) were associated with increased access to SPC for LC patients. Access to SPC correlated with fewer emergency room visits (p < .0001 for both COPD and LC patients) and fewer admissions to acute hospitals during the last month of life (p < .0001 for both groups). More COPD patients died in acute hospitals than lung cancer patients, (39% vs. 20%; χ2 = 287, p < .0001), with significantly lower figures for those who had access to SPC (p < .0001).ConclusionsCompared to dying COPD patients, LC patients have more access to SPC. Access to SPC reduces the need for emergency room visits and admissions to acute hospitals.

Significantly Enhanced Thermoelectric Performance of Graphene through Atomic-Scale Defect Engineering via Mobile Hot-Wire Chemical Vapor Deposition Systems.

Over the years, numerous studies have attempted to develop two-dimensional (2D) materials for improving both the applicability and performance of thermoelectric devices. Among the 2D materials, graphene is one of the promising candidates for thermoelectric materials owing to its extraordinary electrical properties, flexibility, and nontoxicity. However, graphene synthesized through traditional methods suffers from a low Seebeck coefficient and high thermal conductivity, resulting in an extremely low thermoelectric figure of merit (ZT). Here, we present an atomic-scale defect engineering strategy to improve the thermoelectric properties of graphene using embedded high-angle tilt boundary (HATB) domains in graphene films. These HATB domains serve as both energy filtering sites to filter out lower-energy charge carriers and scattering sites for phonons. Compared to the conventionally grown chemical vapor deposited graphene, the graphene with HATB domains shows an improved Seebeck coefficient (50.1 vs 21.1 μV K-1) and reduced thermal conductivity (382 vs 952 W m-1K-1), resulting in a ZT value that is ∼7 times greater at 350 K. This defect engineering strategy is promising not only for graphene-based materials but also for 2D materials, in general, where further research and optimization could overcome the limitations of conventional bulk thermoelectric materials in energy-harvesting systems.