Thoracic Outlet Syndrome

CLINICAL PRESENTATION & EXAM: Thoracic Outlet Syndrome (TOS), a term first coined by Peet in 1956, is a controversial condition that is difficult to diagnose. Commonly characterized by neck and shoulder pain, TOS occurs due to complex mechanisms involving muscular dysfunction and neurovascular compression. Extremely rare in children, TOS affects young women more than men. Patients with a history of trauma around the thoracic outlet area, as well as people who engage in repetitive muscular activity such as competitive baseball pitchers and swimmers, are at an increased risk of TOS. Cases of TOS are classified as vascular (arterial or venous) or neurogenic. In cases of vascular TOS, symptoms can include ischemia in the digits, claudication in the arm, discoloration, pain, and swelling or muscle atrophy. However, about 90-95% of total TOS cases are of the neurogenic type. Patients with this condition may experience numbness, paresthesia, grip weakness, and radiating pain down the arm or to the ear, face, and occiput. ANATOMY & PATHOLOGY: The thoracic outlet is a passageway from the lower neck to the armpit through which veins, arteries, and nerves pass. In TOS, abnormal compression of this area between the clavicle and the first rib results in irritation of the nerves and blood vessels. Most often, muscular dysfunction and imbalance in the cervicoscapular region creates intermittent nerve compression and/or tension on the brachial plexus, resulting in pain and discomfort. TOS can be the result of congenital abnormalities, trauma or injury to the thoracic region, functional acquired causes, and other unidentified sources. DIAGNOSTIC TESTING & CONSIDERATIONS: Due to the diversity of possible symptoms and the variability displayed in patients, TOS presents a diagnostic dilemma to the physician. Diagnosis is based on proper history, physical examination, direct observation and provocation tests, such as Adson’s, Roos’, and Elvy’s maneuvers. These tests consist of manipulating the limbs to add stress onto the thoracic outlet region, thereby eliciting TOS symptoms in less than one minute and assisting in making a diagnosis. Different imaging techniques, such as X-rays and MRIs of the neck and shoulder areas, may be used to reveal a structural abnormality or to locate the site of vascular compression. Nerve conduction tests and an EMG can also be used to detect nerve damage. An arteriography or venography may be performed to inspect vascular functioning. TREATMENT & RETURN TO ACTIVITY: Preventative measures can be taken to correct or eliminate risk factors in regards to the workplace or home ergonomics. If diagnosed early, a conservative approach to treatment consisting of physical therapy can be effective. Exercises that focus on improving posture, increasing range of motion, and stretch muscles around the thoracic outlet can alleviate the symptoms. Non- surgical treatment may also include anesthetic agents, steroids, and botulinum toxin type A (BTX-A) injections. If conservative treatment is ineffective (2-12 months), surgery may be recommended. Typically, the first rib is surgically removed to create more space in the thoracic outlet and alleviate compression on the vessels and nerves. Depending on the severity of the syndrome and the surgeon’s approach to either total or partial removal of the rib and adjacent muscles, outcomes are usually good but a minority of patients may experience a recurrence of symptoms

A Framework for the Flexible Integration of a Class of Decision Procedures into Theorem Provers

The role of decision procedures is often essential in theorem proving. Decision procedures can reduce the search space of heuristic components of a prover and increase its abilities. However, in some applications only a small number of conjectures fall within the scope of the available decision procedures. Some of these conjectures could in an informal sense fall ‘just outside’ that scope. In these situations a problem arises because lemmas have to be invoked or the decision procedure has to communicate with the heuristic component of a theorem prover. This problem is also related to the general problem of how to exibly integrate decision procedures into heuristic theorem provers. In this paper we address such problems and describe a framework for the exible integration of decision procedures into other proof methods. The proposed framework can be used in different theorem provers, for different theories and for different decision procedures. New decision procedures can be simply ‘plugged-in’ to the system. As an illustration, we describe an instantiation of this framework within the Clam proof-planning system, to which it is well suited. We report on some results using this implementation

Complexity of short Presburger arithmetic

We study complexity of short sentences in Presburger arithmetic (Short-PA). Here by "short" we mean sentences with a bounded number of variables, quantifiers, inequalities and Boolean operations; the input consists only of the integers involved in the inequalities. We prove that assuming Kannan's partition can be found in polynomial time, the satisfiability of Short-PA sentences can be decided in polynomial time. Furthermore, under the same assumption, we show that the numbers of satisfying assignments of short Presburger sentences can also be computed in polynomial time

Subclasses of Presburger Arithmetic and the Weak EXP Hierarchy

It is shown that for any fixed $i>0$, the $\Sigma_{i+1}$-fragment of Presburger arithmetic, i.e., its restriction to $i+1$ quantifier alternations beginning with an existential quantifier, is complete for $\mathsf{\Sigma}^{\mathsf{EXP}}_{i}$, the $i$-th level of the weak EXP hierarchy, an analogue to the polynomial-time hierarchy residing between $\mathsf{NEXP}$ and $\mathsf{EXPSPACE}$. This result completes the computational complexity landscape for Presburger arithmetic, a line of research which dates back to the seminal work by Fischer & Rabin in 1974. Moreover, we apply some of the techniques developed in the proof of the lower bound in order to establish bounds on sets of naturals definable in the $\Sigma_1$-fragment of Presburger arithmetic: given a $\Sigma_1$-formula $\Phi(x)$, it is shown that the set of non-negative solutions is an ultimately periodic set whose period is at most doubly-exponential and that this bound is tight.Comment: 10 pages, 2 figure

Television without Frontiers: Opportunity and Debate Created by the New European Community Directive

This Article explores the Directive, passed by the European Council on October 3, 1989, designed to coordinate the various television broadcasting laws of the Member States within the European Community. While the Directive, popularly called Television Without Frontiers, certainly opens up internal frontiers hindering trans-European broadcasting, it contains a controversial local content provision requiring a majority of airtime for European Works which many have argued raises an external barrier to American television programs. This Article explains how the Directive harmonizes the divergent national laws of the Member States and describes in detail the controversy surrounding the local content requirement. In regard to the latter, the Article presents the United States and the Community\u27s positions and outlines the potential responses to the Directive by the United States and its television and film industry

The influence of heat treatment and finishing on the mechanical properties of laminar composites

The aim of this investigation was to define the optimum conditions of obtaining glass fabric - epoxy resin laminar composites with appropriate mechanical properties that satisfy the quality needed for production of printed circuit boards for microelectronics. Commercial materials: domestic glass woven fabric, different types of silane finish and epoxy resin were starting materials in obtaining composites. The conditions needed for the thermal removal of the original size from glass fabric were investigated. The optimal heat treatment should be performed on temperatures less than 550C, while cooling rate should be as slow as possible. In this manner the fabric has less than 0.1% of residual size, and the mechanical properties remain satisfactory. Two most commonly used silane based finishes were applied on heat-treated glass fabric. Tensile strength of the composite material made of thermally and chemically treated glass fabric and epoxy resin was investigated. The possibility of using domestic glass fabric in production of printed circuit boards for microelectronics has been confirmed. Finish with amino functional group and lower heat treatment temperature should be used for obtaining glass-fabric epoxy resin laminar composites with desirable mechanical properties

Influence of hemp particle size and mass ratio of components on mechanical properties of hemp blocks

The aim of the present study is to investigate the performances of hemp block made of hemp shives and CaO binder (lime). In order to improve the performances of cono block, a selection of particle size from 1 mm to 40 mm of hemp shiv was made. The optimization of the mass ratios of the components was also done. The results show that there is a positive effect of reducing the dimensions of the hemp shiv particles on the mechanical properties of the formed cono block. Also, there is a significant influence of the mass ratio of the components on the mechanical properties of the obtained cono blocks.The FirstInternational Conference on Sustainable Environment and Technologies “Creating Sustainable CommUNiTy”, September 24-25 2021, Belgrade, Serbi