Converse Implication Research Articles

Using conversation analysis to explore feedback on resident performance

Feedback on clinical performance of residents is seen as a fundamental element in postgraduate medical education. Although literature on feedback in medical education is abundant, many supervisors struggle with providing this feedback and residents experience feedback as insufficiently constructive. With a detailed analysis of real-world feedback conversations, this study aims to contribute to the current literature by deepening the understanding of how feedback on residents’ performance is provided, and to formulate recommendations for improvement of feedback practice. Eight evaluation meetings between program directors and residents were recorded in 2015–2016. These meetings were analyzed using conversation analysis. This is an ethno-methodological approach that uses a data-driven, iterative procedure to uncover interactional patterns that structure naturally occurring, spoken interaction. Feedback in our data took two forms: feedback as a unidirectional activity and feedback as a dialogic activity. The unidirectional feedback activities prevailed over the dialogic activities. The two different formats elicit different types of resident responses and have different implications for the progress of the interaction. Both feedback formats concerned positive as well as negative feedback and both were often mitigated by the participants. Unidirectional feedback and mitigating or downplaying feedback is at odds with the aim of feedback in medical education. Dialogic feedback avoids the pitfall of a program director-dominated conversation and gives residents the opportunity to take ownership of their strengths and weaknesses, which increases chances to change resident behavior. On the basis of linguistic analysis of our real-life data we suggest implications for feedback conversations.

Logarithmic means of sequences of fuzzy numbers and a Tauberian theorem

A sequence $$(x_n)$$ of fuzzy numbers is said to be summable to a fuzzy number L by the logarithmic mean method $$(\ell ,2)$$ if $$\begin{aligned} \lim _{n\rightarrow \infty }\frac{1}{\ell _n^{(2)}}\sum _{k=1}^{n}\frac{x_k}{k\ell _k}=L \end{aligned}$$where $$\begin{aligned} \ell _n^{(2)}=\sum _{k=1}^{n}\frac{1}{k\ell _k}\sim \log (\log n). \end{aligned}$$We prove that the ordinary convergence of $$(x_n)$$ implies its $$(\ell ,2)$$ summability. The converse implication is not necessarily true. Namely, the $$(\ell ,2)$$ summability of $$(x_n)$$ may not imply the convergence of $$(x_n)$$. However, under certain additional conditions the converse may hold. Such conditions are called Tauberian conditions, and the resulting theorem is said to be a Tauberian theorem. In this paper, we provide necessary and sufficient Tauberian conditions to transform $$(\ell ,2)$$ summable sequences of fuzzy numbers into convergent sequences of fuzzy numbers with preserving the limit.

Reliability Indicators for 2-Dimensional Shear Wave Elastography.

Ultrasound (US) shear wave technology providers have either point shear wave elastography (SWE) or 2-dimensional SWE available on their US systems. With 2-dimensional SWE, larger regions of interest can be interrogated, with both the main acoustic radiation pulses and the resultant shear waves potentially being affected by US artifacts. Some providers assist the operator with elastographic maps indicating the reliability or precision of the shear wave propagation. This Technical Innovation explores the importance of the consideration of the precision maps and standard deviation output available on some devices and the implications for conversion of shear wave speed to pressure.

Classifying matchbox manifolds

Matchbox manifolds are foliated spaces with totally disconnected transversals. Two matchbox manifolds which are homeomorphic have return equivalent dynamics, so that invariants of return equivalence can be applied to distinguish non-homeomorphic matchbox manifolds. In this work we study the problem of showing the converse implication: when does return equivalence imply homeomorphism? For the class of weak solenoidal matchbox manifolds, we show that if the base manifolds satisfy a strong form of the Borel Conjecture, then return equivalence for the dynamics of their foliations implies the total spaces are homeomorphic. In particular, we show that two equicontinuous $\mT^n$--like matchbox manifolds of the same dimension are homeomorphic if and only if their corresponding restricted pseudogroups are return equivalent. At the same time, we show that these results cannot be extended to include the "\emph{adic}-surfaces", which are a class of weak solenoids fibering over a closed surface of genus 2.

Some Tauberian theorems for iterations of Hölder integrability method

Let f be a real or complex-valued function on $$[1,\infty )$$ which is continuous over every finite interval [1, x) for $$1<x<\infty $$ . We set $$s(x):=\int _{1}^{x}f(t)dt$$ and define $$\sigma _{k}(s(x))$$ by $$\begin{aligned} \sigma _{k}(s(x))=\left\{ \begin{array}{ll} \displaystyle {\frac{1}{x}\int _{1}^{x}} \sigma _{k-1}(s(t))dt,&{}\quad k\ge 1\\ s(x),&{}\quad k=0 \end{array} \right. \end{aligned}$$ for each nonnegative integer k. An improper integral $$\begin{aligned} \int _{1}^{\infty } f(x)dx \end{aligned}$$ is said to be integrable to a finite number $$\mu $$ by the k-th iteration of Holder or Cesaro mean method of order one, or for short, the (H, k) integrable to $$\mu $$ if $$\begin{aligned} \lim _{x\rightarrow \infty }\sigma _{k}(s(x))=\mu . \end{aligned}$$ In this case, we write $$s(x)\rightarrow \mu \,\,(H,k)$$ . It is clear that the (H, k) integrability method reduces to the ordinary convergence for $$k=0$$ and the (H, 1) integrability method is (C, 1) integrability method. It is known that $$\lim _{x \rightarrow \infty } s(x) =\mu $$ implies $$\lim _{x \rightarrow \infty }\sigma _{k}(s(x)) =\mu $$ . But the converse of this implication is not true in general. In this paper, we obtain some Tauberian conditions for the iterations of Holder integrability method under which the converse implication holds.

Ferroelectric Properties of Perovskite Thin Films and Their Implications for Solar Energy Conversion.

Whether or not methylammonium lead iodide (MAPbI3 ) is a ferroelectric semiconductor has caused controversy in the literature, fueled by many misunderstandings and imprecise definitions. Correlating recent literature reports and generic crystal properties with the authors' experimental evidence, the authors show that MAPbI3 thin-films are indeed semiconducting ferroelectrics and exhibit spontaneous polarization upon transition from the cubic high-temperature phase to the tetragonal phase at room temperature. The polarization is predominantly oriented in-plane and is organized in characteristic domains as probed with piezoresponse force microscopy. Drift-diffusion simulations based on experimental patterns of polarized domains indicate a reduction of the Shockley-Read-Hall recombination of charge carriers within the perovskite grains due to the ferroelectric built-in field and allow reproduction of the electrical solar cell properties.

General Tauberian theorems for the Cesàro integrability of functions

Abstract For a locally integrable function f on [ 0 , ∞ ) {[0,\infty)} , we define F ⁢ ( t ) = ∫ 0 t f ⁢ ( u ) ⁢ d ⁢ u and σ α ⁢ ( t ) = ∫ 0 t ( 1 - u t ) α ⁢ f ⁢ ( u ) ⁢ d ⁢ u F(t)=\int_{0}^{t}f(u)\mathop{}\!du\quad\text{and}\quad\sigma_{\alpha}(t)=\int_% {0}^{t}\biggl{(}1-\frac{u}{t}\biggr{)}^{\alpha}f(u)\mathop{}\!du for t &gt; 0 {t&gt;0} . The improper integral ∫ 0 ∞ f ⁢ ( u ) ⁢ d ⁢ u {\int_{0}^{\infty}f(u)\mathop{}\!du} is said to be ( C , α ) {(C,\alpha)} integrable to L for some α &gt; - 1 {\alpha&gt;-1} if the limit lim x → ∞ ⁡ σ α ⁢ ( t ) = L {\lim_{x\to\infty}\sigma_{\alpha}(t)=L} exists. It is known that lim t → ∞ ⁡ F ⁢ ( t ) = ℓ {\lim_{t\to\infty}F(t)=\ell} implies lim t → ∞ ⁡ σ α ⁢ ( t ) = ℓ {\lim_{t\to\infty}\sigma_{\alpha}(t)=\ell} for α &gt; - 1 {\alpha&gt;-1} , but the converse of this implication is not true in general. In this paper, we introduce the concept of the general control modulo of non-integer order for functions and obtain some Tauberian conditions in terms of this concept for the ( C , α ) {(C,\alpha)} integrability method in order that the converse implication hold true. Our results extend the main theorems in [Ü. Totur and İ. Çanak, Tauberian conditions for the ( C , α ) (C,\alpha) integrability of functions, Positivity 21 2017, 1, 73–83].

Assessment of soil properties and earthworms in organic and conventional farming systems after seven years of dairy farm conversions in New Zealand

ABSTRACTEnvironmental degradation and consumer awareness are raising concerns about the sustainability of conventional farming while increasing interest in organic farming as an alternative food and fiber production. Well-replicated studies during the transition are necessary for testing the causes of observed changes. To test soil property changes following conversion, we collected data from 18 dairy farms (nine converting and nine that remained under conventional methods) in the Waikato, Taranaki, and Manawatu regions of New Zealand. Soil properties on the converting group were compared with matched farms that continued with conventional methods. Converting to organic did not result in increased total carbon or nitrogen, but phosphorus decreased by 42%. Bulk density decreased by 3.5% in converted farms but increased by 9.8% in conventional farms. Earthworm densities were higher in organic farms but there was no significant change in soil microbial parameters. Total nitrogen was lower where microbial respiration was higher but there was no evidence of a link between earthworms and soil nutrient levels. This observation challenges whether the observed changes in studies of farms that have already converted are indeed caused by organic farming methods themselves. Long-term studies are needed before the broader implications of conversion can be fully assessed.

Considerations for Reducing Aviation’s with Aircraft Electric Propulsion

The reduction of aviation’s emissions is a major objective of the aviation industry. About 98% of the world’s aviation is produced by aircraft with gross takeoff mass above 25 metric tonnes, referred to herein as airliners. Propulsion of such aircraft can require power and energy levels of tens of megawatts and hundreds of thousands of kilowatt hours per flight. The challenges to electrically powering these airliners are examined in the context of reduction. Additional possible benefits such as noise and cost reduction are explored. All electric (battery), hybrid, and turboelectric approaches are considered. Technical issues including weight, efficiency, and heat rejection are examined. In addition, economic and policy implications of an industry conversion to electric propulsion are discussed. The conclusion of this study is that electric propulsion is not a promising path to significant reduction of aviation’s in the first half of the 21st century.

Ball characterizations in spaces of constant curvature

High proved the following theorem. If the intersections of any two congruent copies of a plane convex body are centrally symmetric, then this body is a circle. In our paper we extend the theorem of High to spherical, Euclidean and hyperbolic spaces, under some regularity assumptions. Suppose that in any of these spaces there is a pair of closed convex sets of class C+2 with interior points, different from the whole space, and the intersections of any congruent copies of these sets are centrally symmetric (provided they have non-empty interiors). Then our sets are congruent balls. Under the same hypotheses, but if we require only central symmetry of small intersections, then our sets are either congruent balls, or paraballs, or have as connected components of their boundaries congruent hyperspheres (and the converse implication also holds). Under the same hypotheses, if we require central symmetry of all compact intersections, then either our sets are congruent balls or paraballs, or have as connected components of their boundaries congruent hyperspheres, and either d ≥ 3, or d = 2 and one of the sets is bounded by one hypercycle, or both sets are congruent parallel domains of straight lines, or there are no more compact intersections than those bounded by two finite hypercycle arcs (and the converse implication also holds). We also prove a dual theorem. If in any of these spaces there is a pair of smooth closed convex sets, such that both of them have supporting spheres at any of their boundary points Sd for Sd of radius less than π/2- and the closed convex hulls of any congruent copies of these sets are centrally symmetric, then our sets are congruent balls.

Using Landweber iteration to quantify source conditions – a numerical study

Abstract Source conditions of the type x † ∈ ℛ ⁢ ( ( A ∗ ⁢ A ) μ ) {x^{\dagger}\in\mathcal{R}((A^{\ast}A)^{\mu})} are a standard assumption in the theory of inverse problems to show convergence rates of regularized solutions as the noise in the data goes to zero. Unfortunately, it is rarely possible to verify these conditions in practice, rendering data-independent parameter choice rules unfeasible. In this paper we show that such a source condition implies a Kurdyka–Łojasiewicz inequality with certain parameters depending on μ. While the converse implication is unclear from a theoretical point of view, we propose an algorithm which represents a first attempt that allows to approximate the value of μ numerically. It is based on combining the Landweber iteration with the Kurdyka–Łojasiewicz inequality. We conduct several numerical experiments to demonstrate the potential and limitations of the current method. We also show that the source condition implies a lower bound on the convergence rate which is of optimal order and observable without the knowledge of μ.

Long-Term Implications of Unplanned Conversion During Laparoscopic Liver Resection for Hepatocellular Carcinoma.

Laparoscopic liver resection (LLR) is increasingly utilized for patients with hepatocellular carcinoma (HCC). However, long-term outcomes for patients requiring conversion to an open procedure during LLR have not been examined. Patients undergoing attempted LLR for HCC were identified within the National Cancer Database. Patients undergoing successful LLR were compared with those who required unplanned conversion with regard to perioperative outcomes and overall survival (OS). Those experiencing conversion were further compared with patients who underwent planned open resection after propensity score matching. Unplanned conversion occurred in 228 (18.0%) of 1270 patients undergoing LLR. Compared with successful LLR, conversion was associated with greater length of stay (6 vs. 4days, p < 0.001), higher readmission rates (7.8% vs. 2.6%, p = 0.001), and reduced OS (55.1 vs. 67.6months, p = 0.074). Unplanned conversion during major hepatectomy was associated with significantly worse OS (median 35.7months) compared with successful major and minor LLR (median not reached and 67.6months, respectively, p = 0.004). Compared with planned open resection, similar results were noted as conversion during major LLR was associated with worse OS (median 27.3months) compared with open major hepatectomy (median not reached; p = 0.002). Unplanned conversion was independently associated with increased mortality (hazard ratio 1.38) after adjustment in a multivariable model. Tumor size was the strongest predictor of conversion on logistic regression analysis. Unplanned conversion during LLR for HCC is associated with inferior OS. This difference is most pronounced for major hepatectomy. LLR should be considered cautiously in patients with larger, more advanced tumors likely to require major resection.

Statistical sparsity

The main contribution of this paper is a mathematical definition of statistical sparsity, which is expressed as a limiting property of a sequence of probability distributions. The limit is characterized by an exceedance measure~$H$ and a rate parameter~$\rho > 0$, both of which are unrelated to sample size. The definition is sufficient to encompass all sparsity models that have been suggested in the signal-detection literature. Sparsity implies that $\rho$~is small, and a sparse approximation is asymptotic in the rate parameter, typically with error $o(\rho)$ in the sparse limit $\rho \to 0$. To first order in sparsity, the sparse signal plus Gaussian noise convolution depends on the signal distribution only through its rate parameter and exceedance measure. This is one of several asymptotic approximations implied by the definition, each of which is most conveniently expressed in terms of the zeta-transformation of the exceedance measure. One implication is that two sparse families having the same exceedance measure are inferentially equivalent, and cannot be distinguished to first order. A converse implication for methodological strategy is that it may be more fruitful to focus on the exceedance measure, ignoring aspects of the signal distribution that have negligible effect on observables and on inferences. From this point of view, scale models and inverse-power measures seem particularly attractive.

Nuclear frames in the Irish media: Implications for conversations on nuclear power generation in the age of climate change

Keeping within the temperature limits set by the Paris Agreement on climate action will be a significant challenge. Nuclear power generation may contribute to achieving these targets, however, there are significant environmental, economic and health risks attached. Using qualitative and quantitative methods, this paper explores how nuclear power generation is framed in the Irish print media, and discusses the implications of these frames for how nuclear power is perceived within the context of climate change mitigation in Ireland. Two Irish broadsheet papers, the Irish Times and the Irish Independent were selected for data collection, focusing on Chernobyl and Fukushima incidents. The prevalence of informational and balanced articles suggest that to some extent, an open debate on nuclear is already occurring. Nevertheless, significantly more articles take an anti-nuclear stance (34% in 1986 and 27.5% in 2011) than pro-nuclear (2.1% in 1986 and 3.3% in 2011), reflecting the lack of public appetite for nuclear power. This may limit the potential for a wider debate to occur within the context of reducing domestic emissions. Considering the urgency of addressing climate change, a full and balanced societal debate on how nuclear power, other energy alternatives (e.g. wind) and the energy sector more generally, can contribute to national climate policy targets may be necessary.

Noddings’ “Critical Lessons” May be Particularly Critical at the Elementary Level

This article explores Nel Noddings’ conception of pedagogical neutrality and its meanings and implications for classroom conversations, particularly at the elementary grade levels. It examines the selection of issues for classroom discourse and the importance of teachers purposefully exposing students to arguments and data with which they may be less familiar, especially in more polarized settings. The piece also discusses the extent to which younger students can grapple with controversial issues, and the arguments for and against elementary teachers sharing their views with their students. The piece concludes with examples of, and guidelines for, facilitating effective discussions of controversial issues at the primary and intermediate elementary levels.

A Range Condition for Polyconvex Variational Regularization

In the context of convex variational regularization, it is a known result that, under suitable differentiability assumptions, source conditions in the form of variational inequalities imply range conditions, while the converse implication only holds under an additional restriction on the operator. In this article, we prove the analogous result for polyconvex regularization. More precisely, we show that the variational inequality derived by the authors in 2017 implies that the derivative of the regularization functional must lie in the range of the dual-adjoint of the derivative of the operator. In addition, we show how to adapt the restriction on the operator in order to obtain the converse implication.

Tauberian theorems for iterations of weighted mean summable integrals

Let p be a positive weight function on $$A:=[1, \infty )$$ which is integrable in Lebesgue’s sense over every finite interval (1, x) for $$1<x<\infty $$ , in symbol: $$p \in L^{1}_{loc} (A)$$ such that $$P(x)=\int _{1}^{x} p(t) dt\ne 0$$ for each $$x>1$$ , $$P(1)=0$$ and $$P(x) \rightarrow \infty $$ as $$x \rightarrow \infty $$ . For a real-valued function $$f \in L^{1}_{loc} (A)$$ , we set $$s(x):=\int _{1}^{x}f(t)dt$$ and denote $$\begin{aligned} \sigma ^{(0)}_p(x):=s(x), \sigma ^{(k)}_p(x):=\frac{1}{P(x)}\int _1^x \sigma ^{(k-1)}_p(t) p(t)dt\,\,\, (x>1, k=1,2,\ldots ), \end{aligned}$$ provided that $$P(x)>0$$ . If $$\begin{aligned} \lim _{x\rightarrow \infty }\sigma ^{(k)}_p(x)=L, \end{aligned}$$ we say that $$\int _{1}^{\infty }f(x)dx$$ is summable to L by the k-th iteration of weighted mean method determined by the function p(x), or for short, $$({\overline{N}},p,k)$$ integrable to a finite number L and we write $$s(x)\rightarrow L({\overline{N}},p,k)$$ . It is well-known that the existence of the limit $$\lim _{x \rightarrow \infty } s(x)=L$$ implies that of $$\lim _{x \rightarrow \infty } \sigma ^{(k)}_p(x)=L$$ . But the converse of this implication is not true in general. In this paper, we obtain some Tauberian theorems for the weighted mean method of integrals in order that the converse implication holds true. Our results extend and generalize some classical type Tauberian theorems given for Cesaro and logarithmic summability methods of integrals.

Equivalence after extension and Schur coupling coincide for inessential operators

In recent years the coincidence of the operator relations equivalence after extension (EAE) and Schur coupling (SC) was settled for the Hilbert space case. For Banach space operators, it is known that SC implies EAE, but the converse implication is only known for special classes of operators, such as Fredholm operators with index zero and operators that can in norm be approximated by invertible operators. In this paper we prove that the implication EAE ⇒ SC also holds for inessential Banach space operators. The inessential operators were introduced as a generalization of the compact operators, and include, besides the compact operators, also the strictly singular and strictly co-singular operators; in fact they form the largest ideal such that the invertible elements in the associated quotient algebra coincide with (the equivalence classes of) the Fredholm operators.

"I Am Uncertain About What My Uncertainty Even Is": Men's Uncertainty and Information Management of Their BRCA-Related Cancer Risks.

Men with a germline pathogenic BRCA1 or BRCA2 variant have increased risks for developing breast, pancreatic, prostate, and melanoma cancers, but little is known about how they understand and manage their cancer risks. This study examines how men with BRCA-related cancer risks manage uncertainty and information about their risks. Twenty-five men who were either a BRCA carrier or have a BRCA-positive first-degree family member that put the participant at 50% chance of also being a BRCA carrier were interviewed for this study. Using uncertainty management theory as a theoretical framework, this study demonstrates that men manage uncertainty by seeking information from female family members, websites, and healthcare providers, and are under-informed about their cancer risks. Further, in handling their information, men prefer information about cancer risk percentages and screening recommendations in the form of lists presented to them via websites, printed literature, proactive healthcare providers, and an identifiable male spokesperson. Finally, men used BRCA-related cancer risk information to make decisions about whether or not to engage in screening and prevention, manage their BRCA-related cancer risks, and overall family well-being-yet often at the expense of their own individual risks. Implications for genetic counseling and family conversations are discussed.

KONVERSI AGAMA MIGRAN TORAJA: Motivasi dan Implikasinya terhadap Hubungan Etnik-Religi Toraja di Kota Bontang, Kalimantan Timur

The aim of this paper is to reveal and understand the motives behind and implications of religious conversion among Torajan Muslim converts from migrant community in the City of Bontang, East Kalimantan Province. Applying qualitative-fenomenological method, this research finds out that the main motives behind religious conversion among Torajan Muslim converts is practical and pragmatic benefits such as to perform marriage. However, the combination of Hidayah (spiritual guidance) from Allah, support from other family members, and influence from social environment are also believed to be other significant reasen behind religious conversion among Torajan Muslim converts in Bontang. Despite facing a number of socio-economic problems, post-conversion politics, and inter-ethnic family disputes resulting from the practice of conversion, family relation among Torajan Christians who convert to Islam and those who remain Cristian are well maintained. In the broader context, religious conversion for practical and pragmatical reasons is not always lead to disruptions in terms of inter-religious relations among migrant community of Torajan people despite the fact that those converts are still marginalized in the area of political economy competition. Keywords : Conversion, muallaf, ethnic-religion, Toraja