Some Remarks on the Model Theory of Epistemic Plausibility Models

Classical logics of knowledge and belief are usually interpreted on Kripke models, for which a mathematically well-developed model theory is available. However, such models are inadequate to capture dynamic phenomena. Therefore, epistemic plausibility models have been introduced. Because these are much richer structures than Kripke models, they do not straightforwardly inherit the model-theoretical results of modal logic. Therefore, while epistemic plausibility structures are well-suited for modeling purposes, an extensive investigation of their model theory has been lacking so far. The aim of the present paper is to fill exactly this gap, by initiating a systematic exploration of the model theory of epistemic plausibility models. Like in 'ordinary' modal logic, the focus will be on the notion of bisimulation. We define various notions of bisimulations (parametrized by a language L) and show that L-bisimilarity implies L-equivalence. We prove a Hennesy-Milner type result, and also two undefinability results. However, our main point is a negative one, viz. that bisimulations cannot straightforwardly be generalized to epistemic plausibility models if conditional belief is taken into account. We present two ways of coping with this issue: (i) adding a modality to the language, and (ii) putting extra constraints on the models. Finally, we make some remarks about the interaction between bisimulation and dynamic model changes.Comment: 19 pages, 3 figure

Surgical management of multirelapsed inguinal hernias

USMF “N. Testemițanu”, mun. Chişinău, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Dilema tacticii şi tratamentul herniilor recidivante rămîn pînă acum nerezolvate şi necesită elaborarea metodei mai efective în tratamentul modificării şi restabilirea structurii anatomo-funcționale a regiunii inghinale.Cercetările actuale urmăresc scopul şi demonstrează actualitatea problemei herniilor multirecidivante inghinale şi accentuează avantajul autodermoplastiei în comparație cu alte metode tradiționale în hernioplastie. Material şi metode: Au fost analizați 803 pacienți timp de 10 ani, ce au suportat intervenții a herniilor inghinale, din ei 56 au fost operați pentru hernii inghinale recidivante şi multirecidivante, ce constitue 6,75%. Din lotul bolnavilor examinați şi operați majoritatea constitue bărbații- 96,43%. Statistica ne arată că picul maladiei se află la vîrsta 60-69 ani (37,5%). Rezultate: Recidive nu s-au constatat. Rezultatele acestor operații s-au supravegheat timp de 5 ani după operație. Concluzii: În rezultatul tratamentului chirurgical fenomenul de tensionare a țesutului este absent. Pielea compensează deficitul țesuturilor locale şi permite întărirea pereților posteriori ai canalului inghinal şi formarea inelului inghinal intern. În afară de aceasta apare posibilitatea de a crea un ligament inghinal artificial prin suturarea pielei la lig. Jimbernati şi suprapubian, plus spina iliacă anterioară superioară. Deoarece pielea reprezintă un țesut autogen, nu are loc reacția de reget a transplantului. Lipsa reacției imunologice preîntâmpină apariția țesuturilor cicatriciale.Dilemma of tactics and management of relapsed hernias still remains unresolved and needs elaboration of more effective method in management of disorders and restoration of anatomical and functional structure of the inguen. Present study aims to show the relevance of the problem of multirelapsed inguinal hernias and accentuates the benefits of auto skin grafting in comparison with other traditional methods of hernioplasty. Material and methods: There were analyzed 803 patients who underwent surgery on the inguinal hernias during the last 10 years, 56 of which were operated on for relapsed and multirelapsed hernias, which is 6,75%.The majority of examined and operated patients were men – 96,43%. Statistics indicate that the peak incidence occurs at age of 60-69 years (37,5%). Results: There were no relapses. We followed the results of these operations within 5 years. Conclusions: As a result, after surgical treatment there is no phenomenon of tissue tension. Skin compensates for the lack of local tissue and helps to strengthen the posterior wall of the inguinal canal, and forms the interior inguinal ring. In addition, there is a possibility to create an artificial inguinal ligament, sewing the skin to the Jimbernati and suprapubic ligaments and to the iliac superior anterior spin. Since the skin is an autologous tissue, there is no rejection reaction. The absence of immunological reaction prevents scar tissue

Previsit Multidomain Psychosocial Screening Tools for Adolescents and Young Adults: A Systematic Review.

Adolescence and young adulthood constitute a period when exploratory behaviors can evolve into risky behaviors. Most causes of adolescent ill health are preventable; therefore, it is a priority to detect them early before they turn into health problems. Previsit multidomain psychosocial screening tools are used by professionals to detect and prioritize potentially problematic issues. In conjunction with appropriate clinician training, these tools have improved clinician screening rates in several areas of adolescent health. This article reviews existing multidomain previsit psychosocial screening tools developed in the 21st century and describes their characteristics using a systematic methodology. We reviewed 10,623 records to identify 15 different tools in use since 2000 and described their characteristics. Results show that all tools were developed in high-income countries. The tools provide sufficient coverage of many psychosocial domains relevant to young people's health. However, some psychosocial domains such as screen use and strengths are seldomly addressed. Furthermore, the tools rarely focus on young adults as a target population. Future research should assess the effectiveness, acceptability, and psychometric properties of validated psychosocial screening tools and examine how to expand their use in low- and middle-income countries

On the electromagnetic shielding properties of carbon fiber materials

Introduction. Due to the good electrical and thermal properties of carbon, carbon-based materials represent a major trend is various applications, including electromagnetic compatibility. Among carbon-based materials, graphite-impregnated woven fabrics represent a new trend in the field of electromagnetic shielding, with the perspective of being used for protective clothing. The novelty of the proposed work consists in the exhaustive comparative analysis of various carbon-based sample shields by employing both simulation and experimental methods. The selected configurations included a simple graphite plate, a graphite powder strip network, and a graphite-impregnated fabric with 2´2 twill weave. Purpose. The main scope of the analysis is to prove the efficiency of the graphite-impregnated twill woven fabric in the field of electromagnetic shielding. Methods. Two main research methods were employed: simulation and experiment, both following the same protocol: the shield placed in the middle, with the excitation (transmitting antenna) on one side and the measurement / receiving antenna on the other. The experimental stage was thorough, being performed in two different laboratories and by applying the double transverse electromagnetic (TEM) cell method and the shielded box method. Results. A significant difference yielded from the comparison of the simulation and experimental results for the shielding effectiveness, probably due to the fact that the virtual model is an idealized version of the physical one, not taking into account its imperfections. The virtual analysis yielded the graphite plate shield as the most efficient, followed closely by the twill fabric. The graphite strip network had significantly poorer performance compared to the other two shields, probably due to the electrical contact imperfections between the graphite strips and the optical transparency of the shield. The main focus of the analysis was the twill woven graphite-impregnated fabric; therefore, its shielding effectiveness was determined through simulation and experiment. The experimental analysis was performed in two stages in two different electromagnetic compatibility laboratories, by employing the double TEM cell method and the shielded box method, respectively, both methods providing similar results and classifying the shielding performance as good. Practical value. The paper provides an accurate analysis of the graphite-impregnated 2´2 twill woven fabric in terms of electromagnetic shielding effectiveness, by employing both simulation and experimental methods, and comparing its performance to the one other graphite-based shields.Вступ. Завдяки хорошим електричним і тепловим властивостям вуглецю, вуглецевмісні матеріали являють собою основні напрямки у різних застосуваннях, у тому числі в області електромагнітної сумісності, завдяки хорошим екрануючим властивостям. Серед матеріалів на основі вуглецю просочені графітом тканини є новою тенденцією в області електромагнітного екранування з перспективою використання для захисного одягу. Новизна запропонованої роботи полягає у вичерпному порівняльному аналізі різних зразків екранів на основі вуглецю з використанням як моделювання, так і експериментального методів. Вибрані конфігурації включали просту графітову пластину, сітку зі смуг з графітового порошку і просочену графітом тканину з переплетенням саржею 2´2. Ціль. Основною метою аналізу є доказ ефективності саржевого полотна, просоченого графітом, у галузі електромагнітного екранування. Методи. Використовувалися два основних методи дослідження: моделювання та експеримент, обидва слідували одному й тому ж протоколу: екран розташовувався посередині, з збуджуванням (передаючою антеною) з одного боку і вимірювальною/приймальною антеною з іншого. Експериментальний етап був ретельним і проводився у двох різних лабораторіях із застосуванням методу подвійної поперечної електромагнітної (ПЕМ) комірки та методу екранованої скриньки. Результати. Порівняння результатів моделювання та експериментів стосовно ефективності екранування демонструє суттєву відмінність, ймовірно, через те, що віртуальна модель є ідеалізованою версією фізичної, не враховуючи її недосконалості. Віртуальний аналіз показав, що екран із графітових пластин є найбільш ефективним, за ним близько слідує саржева тканина. Мережа з графітових смуг мала значно гірші характеристики порівняно з двома іншими екранами, ймовірно, через недосконалість електричного контакту між графітовими смужками та оптичною прозорістю екрана. Основним предметом аналізу була тканина саржевого переплетення, просочена графітом; тому її ефективність екранування визначалася шляхом моделювання та експерименту. Експериментальний аналіз був виконаний у два етапи у двох різних лабораторіях електромагнітної сумісності з використанням методу подвійної ПЕМ комірки та методу екранованої скриньки, відповідно, обидва методи дали аналогічні результати та визначили характеристики екранування як хороші. Практична цінність. У статті наведено точний аналіз просоченої графітом саржевої тканини 2´2 з точки зору ефективності електромагнітного екранування з використанням як моделювання, так і експериментальних методів, а також порівняння її характеристик з іншими екранами на основі графіту

Dilemma of tactics and management of voluminous ventral hernias in patients with obesity and pendulous abdomen

USMF “N. Testemițanu”, mun. Chişinău, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Herniile ventrale voluminoase pe fond de obezitate şi abdomen ptozat rămân şi astăzi o problemă. Am hotărât să privim această patologie chirurgicală din punct de vedere al arhitectonicii şi a dinamicii, în dependență de raportul presiunilor parțiale ale cavității toracice şi cavității abdominale în ortostatism.Materiale şi metode: În perioada 1990 şi 2010 în clinică au fost operați 209 de bolnavi cu hernie ventrală voluminoasă pe fond de obezitate şi abdomen ptozat. La pacienții cu obezitate riscul apariției recidivelor creşte de 1,5 ori.Factorii, predispozanți eventrațiilor: hiperlordoza patologică în ortostatism; dereglările cardio-pulmonare pe fond de schimbări a presiunii cavității abdominale; contractura muşchilor antero-ventrali cu deplasarea organelor abdominale în sacul hernial, atrofia şi scăderea tonusului muşchilor drepți abdominali. Intervențiile efectuate – herniotomie cu lichidarea abdomenului ptozat şi modificarea peretelui anteroventral. Ultimilor 20 pacienți au fost efectuate spirometria şi măsurarea tensiunii arteriale pînă şi după intervenției.Rezultate: Luînd în considerare particularități de eventrație la pacienții cu obezitate, am reuşit să dezvoltăm o strategie de tratament, ceea ce a dus la efectuarea intervențiilor plastice selective la pacienții cu hernie pe linia media superior, medie, şi inferior folosind autodermoplastica cu grefă liberă (unu, doi, trei straturi), aplicată cu scufundarea în defect.Concluzii: Restabilirea abdomenului ptozat prin suturarea transversiană bilateral de la plastie; de la teaca muşchilor drepți şi aponevroza muşchilor oblici externi, a dus la scăderea întinderii în regiunea plastiei şi diminuarea apariției recidivelor.Voluminous ventral hernias in obesity and pendulous abdomen are still the problem now. We decided to consider the surgical pathology in terms of architectonics and dynamics, depending on the partial pressure in the chest and abdominal cavity in orthostatic position. Material and methods: 209 patients with ventral hernias in obesity and pendulous abdomen were operated in our clinics during 1990 – 2010. In patients with obesity, risk of recurrence is higher in 1,5 times. Factors that predispose to eventration are pathological hyperlordosis in orthostatic position; cardio-pulmonary disturbances on the background of changes in abdominal pressure; contracture of the anterior abdominal muscles with displacement of the abdominal organs in the hernial sac; atrophy and decreased muscle tone of direct abdominal muscles. The last 20 patients underwent spirometry and measurement of blood pressure before and after the surgery.Results: Taking into account the peculiarities of eventration in obese patients, we were able to develop a treatment strategy that led to the implementation of selective plastic surgery in patients with hernia in the superior, medial and inferior portions of the media line using the auto dermepenthesis with the free flap (one, two, and three layers), used with the immersion into the defect.Conclusions: Restoring the pendulous abdomen by transversal bilateral suturing to the straight muscle sheath and external oblique muscle aponeurosis led to decrease the extent of the region and reduced the occurrence of relapses

Preconception care: advancing from 'important to do and can be done' to 'is being done and is making a difference'

There is a growing evidence base for preconception care--the provision of biomedical, behavioral and social interventions to women and couples before conception occurs. Firstly, there is evidence that health problems, problem behaviours and individual and environmental risks contribute to poor maternal and child health outcomes. Secondly, there are biomedical, behavioural and social interventions that when delivered beforeconception occurs, effectively address many of these health problems, problem behaviours and risk factors.And thirdly, there is emerging experience of how to deliver these interventions in low and middle income countries (LMIC).The preconception care interventions delivered and whom they are delivered to, will need to be tailored to local realities. The package of preconception care interventions delivered in a particular setting will depend on the local epidemiology, the interventions already being delivered, and the resources in place to deliver additionalinterventions. Although a range of population groups could benefit from preconception care, prioritization based on need and feasibility will be needed.There are both potential benefits and risks associated with preconception care. Preconception care could result in large health and social benefits in LMIC. It could also be misused to limit the autonomy of women and reinforce the notion that the focus of all efforts to improve the health of girls and women should be at improving maternal and child health outcomes rather than at improving the health of girls and women as individuals in their own right.There are challenges in delivering preconception care. While the potential benefits of preconception care programmes could be substantial, extending the traditional Maternal and Child Health package will be both a logistic and financial challenge.We need to help countries set and achieve pragmatic and meaningful short term goals. While our longterm goal for preconception care should be for a full package of health and social interventions to be delivered to all women and couples of reproductive age everywhere, our short-term goals must be pragmatic. This is because countries that need preconception care most are the ones least likely to be able to afford them and deliver them.If we want these countries to take on the additional challenge of providing preconception care while they struggle to increase the coverage of prenatal care, skilled care at birth etc., we must help them identify and deliver a small number of effective interventions based on epidemiology and feasibility.Elizabeth Mason, Venkatraman Chandra-Mouli, Valentina Baltag, Charlotte Christiansen, Zohra S Lassi, Zulfiqar A Bhutt

Speakable in Quantum Mechanics

At the 1927 Como conference Bohr spoke the now famous words "It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature." However, if the Copenhagen interpretation really holds on to this motto, why then is there this feeling of conflict when comparing it with realist interpretations? Surely what one can say about nature should in a certain sense be interpretation independent. In this paper I take Bohr's motto seriously and develop a quantum logic that avoids assuming any form of realism as much as possible. To illustrate the non-triviality of this motto a similar result is first derived for classical mechanics. It turns out that the logic for classical mechanics is a special case of the derived quantum logic. Finally, some hints are provided in how these logics are to be used in practical situations and I discuss how some realist interpretations relate to these logics