Книги з теми "Tractor units"

Abstract This book unites recent findings from quantitative and qualitative research from across Africa to illuminate how young men and women engage with the rural economy and imagine their futures, and how development policies and interventions can find traction with these realities. Its 10 chapters are organized around commonly-made foundational claims: that large numbers of young people are leaving rural areas, have no interest in agriculture, cannot access land, can be the engine of rural transformation, are stuck in permanent waithood, and that the rural economy can provide a wealth of opportunity.

This chapter introduces the major philosophical debate about the split-brain phenomenon. Split-brain surgery severs the major white matter fiber tract connecting the two cerebral hemispheres. A number of individuals who underwent this surgery later agreed to act as participants in experiments designed to reveal its psychobehavioral consequences. The basic finding is that, after they are surgically divided in this way, the two hemispheres cannot interact in all the ways they once could: indeed, split-brain subjects sometimes give the impression of having two minds and spheres of consciousness, one associated with each hemisphere. A split-brain subject nonetheless seems to be one of us, at the end of the day. The aim of the book is to reconcile these apparently opposing intuitions by explaining how a split-brain person could have multiple minds.

Urinary tract infections (UTIs) refer to a urine culture yielding a minimum of 100 to 10,000 bacteria units/mm of urine usually from a clean catch midstream sample. This can result from infection of the lower urinary tract involving the bladder (cystitis) or an infection of the upper urinary tract involving the kidneys (pyelonephritis). Uncomplicated UTIs occur in healthy, pre-menopausal, non-pregnant women with a normal urinary tract who have a high likelihood to respond favorably to treatment, but consider local antibiotic resistance patterns. Complicated UTIs occur in women with coexisting pathology, anatomical abnormality, underlying comorbidity, or immunocompromise. Untreated UTIs can progress to pyelonephritis and urosepsis. Asymptomatic bacteriuria for pregnant women can progress very quickly; pyelonephritis carries increased risk of perinatal and neonatal mortality. Pregnant patients should be treated with cephalexin, amoxicillin, or amoxicillin-clavulanic acid (avoiding fluoroquinolones).

♦ Metastatic pathological fractures rarely unite, even if stabilized♦ Never rush to fix a pathological fracture; traction or splintage will suffice while investigations are performed and surgical intervention discussed♦ When surgery is indicated for spinal metastases, both decompression and stabilization are generally required♦ Implants should allow immediate weight-bearing and last the lifetime of the patient♦ Always use a multidisciplinary team.

A urinary tract infection (UTI) is defined as present when urine culture results in the growth of a single organism at greater than 105 colony-forming units/ml of urine. Bowel flora are the commonest cause of UTIs. Escherichia coli accounts for 80% of infections. Klebsiella spp., Proteus mirabilis, Enterococcus faecalis, and Staphylococcal saprophyticus account for most of the remaining 20%. Staphylcoccus aureus culture is usually catheter related or secondary to haematogenous spread. This chapter looks at the symptoms of a UTI, as well as its demographics, complications, diagnosis (including investigations), and treatment. It also discusses prognosis.

The spinal cord and peripheral nerves carry motor and autonomic efferents, as well as sensory afferents connecting the cerebrum with the body. Efferent and afferent fibres form predictable tracts within the spinal cord, forming spinal nerves as they exit the spinal canal. Peripheral nerves are often formed from complicated plexuses of spinal nerves in the cervical, lumbar, and sacral spine. Dermatomes are formed from spinal nerves that innervate specific areas of skin, while myotomes innervate a specific set of muscles. The detailed anatomy of these structures are discussed. Knowledge of the anatomy of these structures is relevant to many clinical situations encountered in the intensive care unit especially with caring for neurological, neurosurgical, orthopaedic, and trauma patients.

In 1973, housewives in California launched what would be the last meat boycott of the twentieth century. And, like its predecessors, the 1973 boycott gained national momentum albeit with little political traction now that Peterson had left public life for a job in the private sector as the consumer advisor to the Giant grocery store chain. And in some quarters of the labor movement, activists drew very clear links between the family economy and the stagnation plaguing workers’ wages. The 1973 boycott led to the founding of the National Consumers Congress, a national organization intended to unite consumer organizers. While it was a short-lived organization, it demonstrates the momentum that consumer activism was building. This chapter also reflects on the lost coordinating opportunity between housewives organizing around consumer issues and the women’s movement in the 1970s.

Imaging the urinary tract of patients in the intensive care unit (ICU) may assist identifying the cause of acute kidney injury (AKI). By the nature of their illness patients on ICU will often be clinically unstable and this will restrict the choice of imaging. Ultrasound is the most commonly used non-invasive imaging technique used, and is essential for assessing renal anatomy, determining kidney size and the presence of obstruction. New developments hold much promise and there are a number of centres now using this technology. Doppler ultrasonography has become increasingly popular to assess intrarenal blood flow. CT scanning can be used with or without contrast when ultrasonography is non-diagnostic and is very useful in identifying calcification within the renal tract. However, the patient must be stable enough for transfer to the radiology department. It is important to consider the risk of iodinated contrast-induced AKI (CI-AKI) in critically-ill patients and minimize potential renal injury. Magnetic resonance imaging may be preferred where there is risk of CI-AKI, but the logistics may prove even more demanding. Renal arteriography is rarely performed, but may be required for diagnostic and interventional procedures for renal artery stenosis or sites of active haemorrhage.

Many patients in the intensive care unit (ICU) suffer from health care-associated infections. Age, immunosuppression, neutropenia, or multi-organ failure are preconditions, but health care-associated infections are largely related to the use of medical devices. Breaches of aseptic technique are the most important risk factor. Central line-associated bloodstream infections, ventilator-associated pneumonia, and catheter-associated urinary tract infections represent up to 75% of all health care-associated infections in the ICU. Ease of diagnosis and effective prevention strategies make the central line-associated bloodstream infection a model of how to diagnose, treat, and prevent health care-associated infections. Identification of ventilator-associated pneumonia is less straightforward and suffers from inconsistent definitions, making surveillance and benchmarking difficult. Catheter-associated urinary tract infection is underestimated in the ICU because clinical signs cannot be assessed in sedated patients. Antibiotic overuse in the ICU selects for multidrug-resistant micro-organisms and thus, broad-spectrum antibiotics must be used to offer empiric treatment of health care-associated infections. Accurate microbiology testing aiming at isolating causative micro-organisms is key to de-escalate antibiotic therapy. Health care-associated infections are preventable, many factors. Successful prevention programmes offer a comprehensive protocol, follow a multidisciplinary approach in preparation, and a multimodal training and education programme in implementation.

Necrotizing enterocolitis 46Necrotizing enterocolitis (NEC) is the most common gastroenterological emergency in the neonatal intensive care unit (NICU) and the major cause of death for all newborns undergoing surgery. The mortality is greater than that from all the congenital disorders of the gastrointestinal tract combined. Survivors may be left with short-bowel syndrome as well as other long-term gastrointestinal, growth and neurodevelopmental sequelae. NEC frequently presents as feed intolerance with bile-stained gastric residuals, abdominal distension, blood in the stools, apnoea, and acidosis. It may develop insidiously, or be a rapidly progressive illness culminating in shock followed by death. The characteristic finding on abdominal radiograph is intramural gas (pneumatosis), produced by bacteria that have invaded the bowel wall. Other radiographic findings include portal gas, persistently dilated loops of bowel and pneumoperitoneum. Immediate management involves stopping enteral feeding, and giving intravenous fluids with broad-spectrum antibiotics. Blood and platelet transfusion may be required. Hypotheses regarding aetiology include the possibility that enteric bacteria ferment maldigested carbohyhdrate creating an acidic intraluminal environment that adversely affects mucosal blood flow. Immaturity of gastrointestinal motor function, digestion, immunity, and circulation are all implicated in the pathogenesis....

The oligodendrocyte–myelin unit subserves saltatory conduction of the nerve impulse in the healthy central nervous system. At one time, many disease processes were thought exclusively to target the structure and function of myelin. Therefore, they were designated ‘demyelinating diseases’. But recent analyses, based mainly on pathological and imaging studies, (re)emphasize that axons are also directly involved in these disorders during both the acute and chronic phases. Another ambiguity is the extent to which these are inflammatory conditions. Here, distinctions should be made between inflammation, as a generic process, and autoimmunity in which rather a specific set of aetiological and mechanistic conditions pertain. And there are differences between disorders that are driven primarily by immune processes and those in which inflammation occurs in response to pre-existing tissue damage.With these provisos, the pathological processes of demyelination and associated axonal dysfunction often account for episodic neurological symptoms and signs referable to white matter tracts of the brain, optic nerves, or spinal cord when these occur in young people. This is the clinical context in which the possibility of ‘demyelinating disease’ is usually considered by physicians and, increasingly, the informed patient. Neurologists will, with appropriate cautions, also be prepared to diagnose demyelinating disease in older patients presenting with progressive symptoms implicating these same pathways even when there is no suggestive past history. Both in its typical and atypical forms multiple sclerosis remains by far the commonest demyelinating disease. But acute disseminated encephalomyelitis, the leucodystrophies, and central pontine myelinolysis also need to be considered in particular circumstances; and multiple sclerosis itself has a differential diagnosis in which the relapsing-remitting course is mimicked by conditions not associated with direct injury to the axon–glial unit. Since our understanding of the cause, pathogenesis and features of demyelinating disease remains incomplete, classification combines aspects of the aetiology, clinical features, pathology, and laboratory components. Whether the designation ‘multiple sclerosis’ encapsulates one or more conditions is now much debated. We anticipate that a major part of future studies in demyelinating disease will be further to resolve this question of disease heterogeneity leading to a new taxonomy based on mechanisms rather than clinical empiricism. But, for now, the variable ages of onset, unpredictable clinical course, protean clinical manifestations, and non-specific laboratory investigations continue to make demyelinating disease one of the more challenging diagnostic areas in clinical neurology.

The largest fiber tract in the human brain is the corpus callosum, which connects the two cerebral hemispheres. A number of surgeries severing this structure were performed on adults in the United States in the second half of the twentieth century. After they are surgically separated from each other in this way, a “split-brain” subject’s hemispheres begin to operate unusually independently of each other in the realms of perception, cognition, and the control of action—almost as if each had a mind of its own. But can a mere hemisphere really see? Speak? Feel? Know what it has done? The split-brain cases raise questions of psychological identity: How many subjects of experience are there within a split-brain subject? How many persons? How many minds? Under experimental conditions, split-brain subjects often act as though they were animated by two distinct conscious beings, evoking the duality intuition. On the other hand, a split-brain subject seems like one of us—not like two of us sharing one body. Split-brain subjects thus also evoke the unity intuition.This book is devoted to reconciling these two apparently opposing intuitions. The key to doing so are facts about the way self-consciousness operates in split-brain subjects. A split-brain subject is composed of two conscious psychological beings that fail to recognize each other’s existence and indeed cannot distinguish themselves from each other. Instead, each must first-personally identify with the split-brain subject as a whole, and in so doing, the two make themselves into one person.

Presented reasearch aimed to develop and analyse the suitability of the CART models for prediction of the extent and probability of occurrence of damage to outer soil layers caused by timber harvesting performed under varied conditions. Having employed these models, the author identified certain methods of logging works and conditions, under which they should be performed to minimise the risk of damaging forest soils. The analyses presented in this work covered the condition of soils upon completion of logging works, which was investigated in 48 stands located in central and south-eastern Poland. In the stands selected for these studies a few felling treatments were carried out, including early thinning, late thinning and final felling. Logging works were performed with use of the most popular technologies in Poland. Trees were cut down with chainsaws and timber was extracted by means of various skidding methods: with horses, semi-suspended skidding with the use of cable yarding systems, farm tractors equipped with cable winches or tractors of a skidder type, and forwarding employing farm tractors with trailers loaded mechanically by cranes or manually. The analyses also included mechanised forest operation with the use of a harvester and a forwarder. The information about the extent of damage to soil, in a form of wheel-ruts and furrows, gathered in the course of soil condition inventory served for construction of regression tree models using the CART method (Classification and Regression Trees), based on which the area, depth and the volume of soil damage under analysis, wheel-ruts and furrows, were determined, and the total degree of all soil disturbances was assessed. The CART classification trees were used for modelling the probability of occurrence of wheel-ruts and furrows, or any other type of soil damage. Qualitative independent variables assumed by the author for developing the models included several characteristics describing the conditions under which the logging works were performed, mensuration data of the stands and the treatments conducted there. These characteristics covered in particular: the season of the year when logging works were performed, the system of timber harvesting employed, the manner of timber skidding, the means engaged in the process of timber harvesting and skidding, habitat type, crown closure, and cutting category. Moreover, the author took into consideration an impact of the quantitative independent variables on the extent and probability of occurrence of soil disturbance. These variables included the following: the measuring row number specifying a distance between the particular soil damage and communication tracks, the age of a stand, the soil moisture content, the intensity of a particular cutting treatment expressed by units of harvested timber volume per one hectare of the stand, and the mean angle of terrain inclination. The CART models developed in these studies not only allowed the author to identify the conditions, under which the soil damage of a given degree is most likely to emerge, or determine the probability of its occurrence, but also, thanks to a graphical presentation of the nature and strength of relationships between the variables employed in the model construction, they facilitated a recognition of rules and relationships between these variables and the area, depth, volume and probability of occurrence of forest soil damage of a particular type. Moreover, the CART trees served for developing the so-called decision-making rules, which are especially useful in organising logging works. These rules allow the organisers of timber harvest to plan the management-related actions and operations with the use of available technical means and under conditions enabling their execution in such manner as to minimise the harm to forest soils. Furthermore, employing the CART trees for modelling soil disturbance made it possible to evaluate particular independent variables in terms of their impact on the values of dependent variables describing the recorded disturbance to outer soil layers. Thanks to this the author was able to identify, amongst the variables used in modelling the properties of soil damage, these particular ones that had the greatest impact on values of these properties, and determine the strength of this impact. Detailed results depended on the form of soil disturbance and the particular characteristics subject to analysis, however the variables with the strongest influence on the extent and probability of occurrence of soil damage, under the conditions encountered in the investigated stands, enclosed the following: the season of the year when logging works were performed, the volume-based cutting intensity of the felling treatments conducted, technical means used for completion of logging works, the soil moisture content during timber harvest, the manner of timber skidding, dragged, semi-suspended or forwarding, and finally a distance between the soil damage and transportation ducts. The CART models proved to be very useful in designing timber harvesting technologies that could minimise the risk of forest soil damage in terms of both, the extent of factual disturbance and the probability of its occurrence. Another valuable advantage of this kind of modelling is an opportunity to evaluate an impact of particular variables on the extent and probability of occurrence of damage to outer soil layers. This allows the investigator to identify, amongst all of the variables describing timber harvesting processes, those crucial ones, from which any optimisation process should start, in order to minimise the negative impact of forest management practices on soil condition.

Anaesthesia induces changes in many organ systems within the body, though clearly none more so than the central nervous system. The physiology of the normal central nervous system is complex and the addition of chronic pathology and polypharmacy creates a significant challenge for the anaesthetist. This chapter demonstrates a common approach for the anaesthetist and specific considerations for a wide range of neurological conditions. Detailed preoperative assessment is essential to gain understanding of the current symptomatology and neurological deficit, including at times restrictions on movement and position. Some conditions may pose challenges relating to communication, capacity, and consent. As part of the consent process, patients may worry that an anaesthetic may aggravate or worsen their neurological disease. There is little evidence to support this understandable concern; however, the risks and benefits must be considered on an individual patient basis. The conduct of anaesthesia may involve a preference for general or regional anaesthesia and requires careful consideration of the pharmacological and physiological impact on the patient and their disease. Interactions between regular medications and anaesthetic drugs are common. Chronically denervated muscle may induce hyperkalaemia after administration of succinylcholine. Other patients may have an altered response to non-depolarizing agents, such as those suffering from myasthenia gravis. The most common neurological condition encountered is epilepsy. This requires consideration of the patient’s antiepileptic drugs, often relating to hepatic enzyme induction or less commonly inhibition and competition for protein binding, and the effect of the anaesthetic technique and drugs on the patient’s seizure risk. Postoperative care may need to take place in a high dependency unit, especially in those with limited preoperative reserve or markers of frailty, and where the gastrointestinal tract has been compromised, alternative routes of drug delivery need to be considered. Overall, patients with chronic neurological conditions require careful assessment and preparation, a considered technique with attention to detail, and often higher levels of care during their immediate postoperative period.

An analysis of the existing literature on the issue of damage to regeneration caused by timber harvesting, revealed that a great majority of results reported in those publications was obtained through laborious and time-consuming field research conducted in two stages. Field research methods for gathering data, employed by various authors, differed in terms of the manner of establishing trial plots, the accuracy of counting and evaluating the number of saplings growing on the investigated sites, classification systems used for distinguishing particular groups of regeneration based on quantitative (diameter at breast height, tree height) and qualitative features (biosocial position within the certain layer and the entire stand), classification systems used for identifying types of damage caused by cutting and felling, as well as transporting operations, and finally the duration of observation intervals and time spent on gathering data on the response of damaged saplings from both, the individual and collective perspectives. Obviously, the most reliable manner of gathering such data would be to count all damaged elements of the environment being a subject of interest of particular investigators at the certain point of time. However, due to time and work consumption of this approach, which is besides very costly, any research should be designed in such a manner as to reduce the above-mentioned factors. This paper aimed to (1) analyse the probability of occurrence of damage to regeneration depending on the form of timber assortments dragged from the felling site to the skidding routes, and timber harvesting technology employed in logging works, and (2) identify a method ensuring that gathered data is sufficient for performing reliable evaluation of share of damage to regeneration at acceptable accuracy level, without necessity to establish trial plots before commencing harvesting works. The scope of these studies enclosed a comparison between two motor-manual methods of timber harvesting in thinned stands, with dragging of timber in the first stage of skidding from the stand to landings. According to one of these methods, a classical one, operations of felling and delimbing of trees were carried out by sawmen at the felling site. Timber obtained using different methods was skidded by carters and horses, and operators of a light-duty cable winch, driven by the chainsaw’s engine, as well as operators of cable winches combined with farm tractors. In the latter, alternative method, sawmen performed only cutting and felling of trees. Delimbing and cross-cutting of trunks, dragged from the felling sites, was carried out by operators of processors combined with farm tractors, worked on skidding routes. The research was conducted in the years 2002–2010 in stands within the age classes II–IV mostly, located in the territories of Regional Directorates of State Forests in Krakow and Katowice, and in the Forest Experimental Unit in Krynica-Zdrój. In the course of a preliminary stage of investigations 102 trial plots were established in stands within early and late tinning treatments. As a result of the field research carried out in two stages, more than 3.25 thsd. circular sites were established and marked, on the surface of which over 25 thsd. saplings constituting the regeneration layer were inventoried. Based on the results of investigations and analyses it was revealed that regardless of the category of thinning treatment, the highest probability of occurrence of destroying P(ZN) to regeneration (0.24–0.44) should be expected when the first stage of timber skidding is performed using cable winches. Slightly lower values of probability (0.17–0.33) should be expected in stands where timber is skidded by horses, while in respect to processor-based skidding technology the probability of destroying occurrence oscillates between 0.12 and 0.27, depending on the particular layer of regeneration. P(ZN) values, very close to those of skidding technology engaging processors, were recorded for skidding performed using the light-duty cable winch driven by the chainsaw’s engine (0.16–0.27). The highest probability of damage P(USZK) to regeneration (0.16–0.31) can be expected when processors are used in the first stage of timber skidding. Slightly lower values of probability (0.14–0.23) were obtained when skidding was performed with the use of cable winches, whereas engaging horses for hauling of trunks results in probability of damage occnrrence oscillating between 0.05–0.20, depending on the particular layer of regeneration. With regard to the probability of occurrence of both, destroying and damage P(ZNUSZK) to regeneration (0.33–0.54), the highest values can be expected when cable winches are engaged in the first stage of skidding. Little lower (0.30–0.43) was the probability of their occurrence if processor-based technology of skidding was employed, while in respect to horse skidding these values oscillated between 0.27–0.41, depending on the layer of regeneration. The lowest values of probability of occurrence of damage P(USZK), and destroying and damage treated collectively P(ZNUSZK), within all layers of regeneration, were recorded in stands where thinning treatments were performed using the light-duty cable winch driven by the chainsaw’s engine. The models evaluated and respective equations, developed based on those models, for evaluating the number of destroyed saplings ZNha (tab. 40, 42, 44, 46, 48) could be used for determining the share of damage expressed as a percentage, upon conducting only one field research at the investigated felling sites, once the timber harvesting and skidding would have been completed. As revealed by the results of analyses, evaluation of statistically significant regression models was possible for all layers of regeneration (tab. 39, 41, 43, 45, 47). Nevertheless, the smallest part of these models that could be considered positively verified, were those for the natural young regeneration, although almost a half of them revealed to be significant. Within the medium-sized regeneration over three-fourths of all models could be considered positively verified, four of which explained more than 50% of variability. Within the high-sized regeneration almost two-thirds of evaluated regression models were statistically significant, five of which were verified positively, moreover, one of them explained more than 50% of variability. The most promising results were those obtained for the advance growth. Nearly 90% of the evaluated models revealed to be statistically significant, ten of which could be considered positively verified. Furthermore, four statistically significant models explained over 50% of general variability. With regard to the entire regeneration more than 80% of evaluated models were statistically significant. However, due to insignificant coefficients of regression, eight of them could be considered positively verified. At this point it should be stressed that in respect to logging technology employing the light-duty cable winch FKS it was impossible to evaluate statistically significant models of regression. Whereas, in the case of processor-based logging technology, firstly regarding the advance growth, and then the entire regeneration, all of the evaluated statistically significant models could be considered positively verified, in terms of both, all of the stands, and particular categories of thinning treatments individually. This latter case also revealed the highest degree of matching of evaluated models (R2 popr 0.73–0.76 for advance growth and 0.78–0.94 for the entire regeneration). A significant impact of the kind of form of hauled timber on the probability of damage occurrence P(USZK), mainly in early thinning treatments, could have been reflected in the results obtained for all stands (early and late thinning treated collectively). Moreover, due to an insignificant impact of the form of hauled timber and logging technology employed, on the probability of occurrence of damage in late thinned stands, and a significant impact of the above-mentioned variables on early thinned stands, it should be assumed that for performing an evaluation of destroying and damage caused by timber harvesting the both thinning treatment categories should be analysed separately. Furthermore, when evaluating the probability of occurrence of destroying and damage caused by timber harvesting, the layers of natural young regeneration and advance growth should be analysed separately. As proved by the results presented in this paper, varying values of probability computed for each of the layers of regeneration seem to indicate that when investigating damage to regeneration caused by timber harvesting, it would be reasonable and recommended to perform a separate analysis of damage to the highest saplings as well, namely individuals with diameter at breast height close to 7 cm. In respect to studies on damage to regeneration caused by logging technologies mentioned above, the evaluation of number of destroyed saplings within the advance growth can be carried out using the proportions of damaged and undamaged saplings per 1 ha of the stand. The numbers evaluated in this manner can be used to calculate the damage share expressed in relative values (percentage of damaged saplings compared with the entire number of saplings before commencing the logging works). However, one should keep in mind that this is true only if the field research have been carried out based on the methodology described in this paper.