Age related cataracts are one of the major causes of loss of vision worldwide. Approximately 20 million people in the United States have their vision obstructed by cataracts and 500,000 new cases are diagnosed annually. The treatment for cataract is surgical extraction. The surgery is more than 95% successful in significantly improving vision. Because of continual advancements in cataract surgery, it is almost exclusively performed as an outpatient procedure and involves the administration of local anesthesia. For the most part patients are fully conscious during the procedure and it is imperative that they remain still. In the elderly, fear of loss of vision related to cataract surgery is second only to the fear of death. Although studies have shown that the average cataract patient is not unduly anxious regarding cataract surgery, anxiety is a known entity. An increase in anxiety can cause a patient to be restless, jittery, and agitated, all of which can cause unanticipated movement and hence a deleterious outcome. People are social beings. Interaction with and among other people provides and conveys support, comfort, and reassurance. Touch, specifically hand holding, has been shown to decrease anxiety and stress in multiple situations. It is minimally invasive, safe, reassuring and could allow patients to communicate during procedures where verbal communication, if done without parameters, as in cataract surgery, could be devastating. The findings of this study failed to reveal a significant difference in post op anxiety scores in either the treatment group or the non treatment group. However, subjectively, those people who received hand holding strongly agreed that hand holding helped to decrease anxiety during the procedure. The physician rating for patient compliance did not reveal a significant level of increase with the intervention during surgery. Again, subjectively, the majority of patients strongly agreed that hand holding did help them to be more compliant to the surgeon’s request. None of the participants that received hand holding felt an intrusion of personal space during the treatment. Results strongly suggest, at least subjectively, that hand holding is beneficial in decreasing anxiety, increasing compliance to intraoperative request, and is much welcomed, beneficial nursing intervention. / Thesis / Master

ABSTRACT BACKGROUND. There have been few studies conducted in hospitalized patients in Viet nam on the epidemiology of surgical site infections (SSIs) and the impact of hand hygiene practices. This study aimed to assess the impact of a bedside hand sanitizer program on SSIs in orthopaedic and neurosurgical patients. DESIGN. A prospective quasi-experimental study was conducted with an untreated control group design in neurosurgical patients and before-after design in orthopaedic patients. A cost analysis based on data derived from the results of this study was also performed. SETTING. Cho Ray Hospital, a tertiary university hospital in Ho Chi Minh City, Viet nam. PATIENTS. All patients admitted for operation between 11 July and 15 August 2000 (Before), and 14 July and 18 August 2001 (After) were included, except those who had undergone another operation within one month prior to admission or were admitted because of SSIs. INTERVENTION. Bedside hand sanitizers were introduced into the Orthopaedic ward and one Neurosurgical ward (Ward A) from September 2000. Training on proper use was also provided to ward staff. Another Neurosurgical ward (Ward B) was used as a control group with no intervention conducted. RESULTS. A total of 1368 patients were recruited into the study. After intervention, in Ward A of the neurosurgical department, the SSI rate between the two periods was reduced by 54% (8.3% to 3.8%; p=0.09). Superficial SSIs were eliminated after the intervention (p=0.007). Comparison between Ward A (intervention) and Ward B (control) showed that, before the intervention, there was no difference in incidence of SSI between the two wards (Ward A: 8.3%, Ward B: 7.2%, p=0.7); however, after intervention, the incidence of SSI in Ward A was significantly lower than Ward B (3.8% and 9.2%, p=0.04). For orthopaedic patients, the SSI rate between the two periods was reduced by 34% (14.8% to 9.8%; p=0.07). SSI patients had a median post-operative length of stay of 19 days longer than patients without SSI (p&lt0.001). Costs were 2.5 times higher in patients with in-hospital SSI compared to uninfected patients (p&lt0.001). Mean SSI-attributable costs were conservatively estimated at US$368 in neurosurgical patients and US$207 in the orthopaedic patients in the before period. SSIs were responsible for at least 14 percent of the annual budget before intervention. The savings per SSI prevented were estimated at US$332 in neurosurgical patients and US$157 in orthopaedic patients. Annual cost savings arising from the intervention were estimated at US$11,112 in orthopaedic patients and US$19,320 in neurosurgical patients. CONCLUSIONS. The incidence of SSI in the hospital was high. The use of hand sanitizers reduced SSI rates, particularly impacting on the incidence of superficial SSIs. The hand sanitization program was found to be a dominant intervention being both more effective and cost saving as compared with no intervention in both study departments. The use of bedside hand sanitizers should be encouraged in the hospitals in Viet nam, where there often is a lack of other hand-washing facilities. / PhD Doctorate

In this report, a method for exploiting the redundancy of a hand-arm mechanical system for manipulation tasks is illustrated. The basic idea is to try to exploit the different intrinsic capabilities of the arm and hand subsystems. The Jacobian transpose technique is at the core of the method: different behaviors of the two subsystems are obtained by means of constraints in Null(J) generated by non-orthogonal projectors. Comments about the computation of the constraints are reported in the memo, as well as a description of some preliminary experiments on a robotic system at the A.I. Lab., M.I.T.

The Psittacidae is one of the most endangered families of birds in the world. Knowledge of its nutrition is important for understanding their survival and productivity in the wild, as well as for their adequate husbandry in captivity. Hand-rearing is a common practice for this group. However, research on their requirements is limited. Analysis of the crop content of chicks can provide new insights into psittacine nutrition, but it is limited by the small sizes of samples which can be obtained. We sampled the crops from free-living chicks of scarlet macaws and red-and-green macaws from southeastern Peru, Cuban parrots from the Bahamas, lilac-crowned parrots from northwestern Mexico, and thick-billed parrots from northern Mexico. The predicted metabolizable energy, protein, fat, minerals, profile of essential amino acids and profile of fatty acids of the crop samples, as well as from 15 commercial hand-rearing formulas, were analyzed and contrasted. Near Infrared Spectroscopy was shown to be a valid technique for the nondestructive, low cost prediction of a variety of nutritional attributes of crop samples as small as 0.5 g dry weight, expanding the possibilities of wild animal nutrition research. The diets of the five studied species presented remarkable similarities and common patterns. The predicted dietary metabolizable energy and fat concentrations were particularly similar among species, the thick-billed parrot being the one with the most unique nutrient profile. The fatty acid profile of the crop contents differed markedly among genera, with the thick-billed parrot closer to the macaws than to the parrots. In comparison with the crop samples, the hand feeding formulas presented lower fat, Mg, arginine, and valine concentrations. The wide variation in nutrients suggests that there is not yet a consensus among manufacturers concerning the correct nutrition for growing psittacines. It is suggested that a single formulation could be used to hand-rear macaws and parrots from half its nesting time to fledging, and further research should focus on their nutrition during the first half. Our results suggest that manufacturers should evaluate if increasing the concentrations of crude fat, Mg, arginine, and valine in commercial formulas enhances psittacine chick growth and health.

Essential metals like Ca2+ and Zn2+ play critical roles in biological processes through protein interactions. Conversely, non-essential metals (e.g., Gd3+ and Pb2+) also interact with proteins, often with toxic effects. Molecular metal toxicity is assumed to be due to ionic displacement, and studies have demonstrated that Pb2+ replaces Zn2+, Ca2+ and other essential metals in proteins. The focus of this work was to compare protein Ca2+ and Pb2+ -binding sites and to investigate a mechanism of Pb2+ toxicity in Ca2+-binding proteins, particularly the intracellular trigger protein calmodulin (CaM) which binds four Ca2+ ions and interacts with numerous molecular targets via Ca2+-induced conformational change. A statistical analysis of PDB structural data for Pb2+ and Ca2+-binding (EF-hand and non-EF-hand) proteins revealed fewer binding ligands in Pb2+ sites (4 ± 2), than non-EF-Hand (6 ± 2) and EF-Hand (7 ± 1) Ca2+-binding sites. Pb2+ binds predominantly with sidechain Glu (38.4%), which is less prevalent in both non-EF-Hand (10.4%) and EF-Hand (26.6%) sites. Interestingly, analyses of proteins where Pb2+ replaces Ca2+ (calmodulin) or Zn2+ (5-aminolaevulinic acid dehydratase) revealed structural changes presumably unrelated to ionic displacement. These results suggested that Pb2+ adopts diverse binding geometries and that opportunistic binding outside of known Ca2+-binding sites may play a role in molecular metal toxicity. Ca2+-binding affinities (Kd) using phenylalanine and tyrosine fluorescence were found to be 1.15 ± 0.68 X 10-5 M and 2.04 ± 0.02 X 10-6 M for the N- and C-terminal domains, respectively. The Kd for Pb2+-binding in the N-terminal domain, 1.40 ± 0.30 X 10-6 M, was 8-fold higher than Ca2+. Binding of Pb2+ in the C-terminal domain produced a biphasic response with Kd values 7.34 ± 0.95 X 10-7 M and 1.93 ± 0.32 X 10-6 M, suggesting a single higher affinity Pb2+-binding site in the C-terminal domain with nearly equivalent affinity for the remaining sites. Competitive effects of Pb2+ added to Ca2+-loaded CaM were examined using multiple NMR techniques. Pb2+ was found to displace Ca2+ only in the N-terminal domain, however structural/dynamic changes were observed in the central helix apparently due to Pb2+-binding in secondary sites. These data supported our hypothesis that CaM structure and function is altered by opportunistic Pb2+-binding.

Job rotation is recommended to prevent musculoskeletal disorders (MSD). The premise is by involving different tissues a “working rest” for other tissues is created. The possible health benefits from this relief have not been investigated with regards to different grips in hand intensive jobs. The purpose of this study is to investigate hand intensive tasks and determine whether rotating between the power grip and lateral pinch grip can provide a benefit. A psychophysical load adjustment protocol was used. To investigate the effect of rotation, three different trials were collected. These included: power grip only, lateral pinch only, and alternating the two grips. Each trial was 60 minutes in duration, with a 12second cycle time, and 25% duty cycle. Fourteen subjects were recruited and pre-screened for any upper extremity disorders. Subjects were instructed to “work as hard as you can without straining your hand, wrist or forearm”; by adjusting their resistance settings to achieve a maximum acceptable force (MAF). Grip forces were exerted on an adjustable system using a hand grip dynamometer. Ratings of perceived discomfort were reported every 10minutes. Electromyography (EMG) was collected on eight forearm muscles during the combination trial. The demand for both lateral pinch and power grip tasks were at self selected levels and no fatigue was reported within MAF, EMG recordings, and discomfort reports. The rotation between lateral pinch and power grip had no apparent effect on MAF. However, EMG data hinted that there was a rotation of activation between first dorsal interossei and the forearm flexors (not statistically significant). Less discomfort was reported within the combination trial than the single grip (not significant). The study found no measurable difference in MAF when rotating between the power grip and lateral pinch. Considering there was no increase in demand, there is potential benefit to rotation, with trends to rotating activation between muscles, less discomfort being reported, and a general preference for the rotation. Given the high rates of MSD, and rotation being an effective tool to lower exposure, further investigations are required to understand relationships between similar muscles groups within hand intensive work environments.

Idag räcker det sällan med att shopping och konsumtion fyller ett praktiskt behov; det ska helst också vara roligt och lustfyllt. Att dagens konsumenter ställer högre krav gör att spelreglerna på marknaden har förändrats. Mossberg (2003) och Hultén, Broweus och van Dijk (2008) konstaterar att en ny typ av marknadsföring håller på att växa fram, där fokus flyttas från produkten och dess egenskaper till att produkten och inköpet ska ses som en upplevelse. Ett sätt att öka kundernas upplevelse i butik är att skapa en tilltalande butiksatmosfär. Dessvärre saknar många svenska butikschefer kunskaper om hur det arbetet kan gå till. Uppsatsens syfte är att lyfta fram frågan om butiksatmosfärens betydelse, och då framförallt för butiker inom second hand-branschen. Jag vill genom undersökningen ta reda på varför second hand-butiker i större utsträckning än andra butiker uppvisar brister i butiksatmosfärens utformning. I undersökningen framkommer att butiksatmosfärens utformning till stor del beror på butikens ekonomiska förutsättningar. Den undersökta butiken drivs av en välgörenhetsorganisation, och därmed har butikschefen stor press att hålla nere kostnaderna så mycket som möjligt. Undersökningen visar dessutom att kunderna i second hand-butiker inte värdesätter en tilltalande butiksatmosfär särskilt högt. Andra faktorer såsom låga priser, ett unikt sortiment och möjlighet att handla miljövänligt värdesätts mer. Kunderna uppger dock att vissa förändringar i butiksatmosfären skulle kunna göra deras besök enklare och trevligare. Ett utökat kundutrymme, mindre varor i butiken samt bättre belysning är förändringar som välkomnas av den undersökta butikens kunder. För second hand-butikers icke-kunder har butiksatmosfären också betydelse då den till viss del ligger bakom deras undvikande beteende. Att de upplever butiken som rörig och ofräsch tycks ha en avskräckande effekt. För att omvandla icke-kunderna till kunder krävs dock mer än en förändring i butiksatmosfären då de har en allmänt negativ inställning till att handla begagnade varor. Butiksatmosfärens utformning bör av den anledningen istället utgå från de befintliga kundernas åsikter och önskemål.

Job rotation is recommended to prevent musculoskeletal disorders (MSD). The premise is by involving different tissues a “working rest” for other tissues is created. The possible health benefits from this relief have not been investigated with regards to different grips in hand intensive jobs. The purpose of this study is to investigate hand intensive tasks and determine whether rotating between the power grip and lateral pinch grip can provide a benefit. A psychophysical load adjustment protocol was used. To investigate the effect of rotation, three different trials were collected. These included: power grip only, lateral pinch only, and alternating the two grips. Each trial was 60 minutes in duration, with a 12second cycle time, and 25% duty cycle. Fourteen subjects were recruited and pre-screened for any upper extremity disorders. Subjects were instructed to “work as hard as you can without straining your hand, wrist or forearm”; by adjusting their resistance settings to achieve a maximum acceptable force (MAF). Grip forces were exerted on an adjustable system using a hand grip dynamometer. Ratings of perceived discomfort were reported every 10minutes. Electromyography (EMG) was collected on eight forearm muscles during the combination trial. The demand for both lateral pinch and power grip tasks were at self selected levels and no fatigue was reported within MAF, EMG recordings, and discomfort reports. The rotation between lateral pinch and power grip had no apparent effect on MAF. However, EMG data hinted that there was a rotation of activation between first dorsal interossei and the forearm flexors (not statistically significant). Less discomfort was reported within the combination trial than the single grip (not significant). The study found no measurable difference in MAF when rotating between the power grip and lateral pinch. Considering there was no increase in demand, there is potential benefit to rotation, with trends to rotating activation between muscles, less discomfort being reported, and a general preference for the rotation. Given the high rates of MSD, and rotation being an effective tool to lower exposure, further investigations are required to understand relationships between similar muscles groups within hand intensive work environments.

Maximum voluntary forces and psychophysically acceptable forces are often used to set force guidelines for exertions as a means to protect against overexertion injuries in the workplace. The focus of this dissertation was the exploration of the roles of whole body balance, shoe-floor friction and joint strength in limiting the capacity of a person to produce maximum voluntary hand forces and psychophysically acceptable hand forces. The underlying goal was to advance knowledge regarding how physical exertion capacity is biomechanically governed, then to use this information to develop models to predict capability based on these governing principles. The hypothesis underscoring this work was that maximum voluntary hand force capability is governed by whole body balance, shoe-floor friction and joint strength; and consequently, psychophysically acceptable forces would be chosen proportionally to this maximum voluntary force capability, where the magnitude of the proportionality was dependent on the limiting factor, or ‘weakest link’. To investigate this hypothesis, both experimental and mathematical modeling paradigms were used. Initially, an experimental study was used to investigate how biomechanical factors governed maximum hand force capability across a range of exertions. It revealed that each governing factor differentially limited maximum force capability. Moreover, this study identified how foot placement, handle height, distance from the handle, friction, and body posture all influence the underlying biomechanical weakest link, and ultimately force producing capability. Data gathered in the experimental study was next used to evaluate a mathematical model that was developed to predict maximum force capability, given information on posture and direction of force application. In addition, the model also predicted population variability in maximum capacity based on the inclusion of a novel approach to probabilistically represent population variability. The evaluation demonstrated that the model underestimated maximum hand force capability compared to measured hand forces by approximately 18, 26, and 41% during medial, pulling and downward exertions respectively. However, it appeared that the ‘weakest link’ principle for predicting maximum force capacity was plausible, as evidenced by significant rank ordered correlations between the measured and predicted hand forces. Further research investigated if psychophysically acceptable forces were selected as a proportion of task specific maximum voluntary force capability, where the proportionality was related to the biomechanical weakest link. Using an experimental design, psychophysically acceptable forces and corresponding maximum forces were measured. Participants chose psychophysically acceptable forces that were 4/5ths of their task specific maximum voluntary force capability when capability was limited by balance. Additionally, they choose psychophysically acceptable forces that were 2/3rds of their maximum voluntary force capability when capability was limited by joint strength. The identification and confirmation of a weakest link proportionality principle represents an important contribution to the field of occupational biomechanics. The weakest link proportionality principle was integrated into the model to allow prediction of: maximum voluntary hand force capability, the limiting factor, and psychophysically acceptable hand force capability. The updated model underestimated empirically measured psychophysically acceptable forces by 24% and 43% during downward and pulling exertions respectively. However, the original model underestimated the maximum hand force capacity by 23% and 34% during the same exertions, without the proportional relationships. This underestimation may be a result of the underlying assumption that joint strength is independent, resulting in an underestimation of maximum joint strength capacity and a corresponding underestimation of maximum hand force capacity. The underestimation may also be due to differences in strength capacities between the participants tested during this thesis compared to those tested in past research used to determine the maximum strength indices reported in the literature. This body of work supported the hypothesis that psychophysically acceptable forces are selected as a proportion of the maximum voluntary hand force, where the proportionality depends on the underlying biomechanical weakest link. The model is a promising first step towards predicting maximum and psychophysically acceptable occupational force threshold limits.

Functional recovery of the upper limb after stroke is influenced by many factors, one being amount of affected arm and hand use following stroke. In the healthy population, amount of hand use is influenced by degree of hand dominance. Depending on side of stroke and previous hand dominance, these preferences may be altered, consequently affecting the amount of upper limb use. Determining hand preference in patients after stroke, when measured, is commonly assessed with questionnaires; however, these reports are subjective and patients may have difficulty recalling from memory which hand they use for the numerous activities on the questionnaire. A preferential reaching task has been shown to correlate with the degree of hand dominance as determined by the Waterloo Handedness Questionnaire, providing an objective performance-based method to assess the continuum of hand dominance in healthy subjects. A modified version of this preferential reaching task, with varying degrees of proximal to distal control, was used to investigate the influence of impairment, pre-stroke dominance and task difficulty on affected arm reach percentage. Results of the study revealed that it is feasible to administer a modified preferential reaching task in the stroke population, as the test could be completed in less than 10 minutes with no adverse effects reported from the patients. Heterogeneity made it difficult to detect statistical effects of task difficulty and pre-stroke dominance on post-stroke preference; however, there were trends observed indicating that patients with their dominant arm affected may have greater preference for the affected arm compared to those with their non-dominant arm affected. This was despite similar impairment levels between these patient groups. Preference for the dominant arm (whether affected or unaffected) was stronger when the task was at midline or in contralateral space, and when tasks required the greatest degree of distal control. In future, the degree of hand preference measured with this tool will have important implications for identifying areas in therapy requiring greater focus as well as identifying individuals who would most benefit from therapies that promote affected arm use, such as constraint induced movement therapy