1,032 research outputs found
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Cuba: An Economic Primer
This report provides an overview of the Cuban economy. Recent congressional interest in Cuba has centered on the partial lifting of trade sanctions on agricultural products and medicine. The 107th Congress may consider further easing of sanctions or other alterations to the trade embargo in effect since 1962. The paper first presents a brief historical overview of the Cuban economy. This history is characterized by dependence on major powers: first Spain, then the United States, and then the Soviet Union. The report then charts the different, and often conflicting, economic policy courses that Fidel Castro has pursued since his rise to power in 1959
Behavioral Evaluation of Modafinil and The Abuse-related Effects of Cocaine in Rhesus Monkeys
This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.Modafinil is a central nervous system stimulant used to promote wakefulness, and it is being evaluated clinically as an agonist-based medication to treat stimulant abuse. This is the first report of the effects of modafinil on the abuse-related effects of cocaine in nonhuman primates. Three studies were conducted to examine the behavioral effects of modafinil. In the first study, the discriminative stimulus effects of modafinil were evaluated in monkeys trained to discriminate either low (0.18 mg/kg, IM) or high (0.4 mg/kg, IM) doses of cocaine from saline. Modafinil dose-dependently substituted for cocaine in 6/7 monkeys. In the second study, the effects of chronically administered modafinil (32-56 mg/kg/day, IV) on food- and cocaine-maintained operant responding were examined. Modafinil was administered 3 times/hr for 23 hr/day to ensure stable drug levels. Chronic treatment with 32 mg/kg/day modafinil selectively reduced responding maintained by intermediate (0.003 mg/kg/inj) and peak (0.01 mg/kg/inj) reinforcing doses of cocaine, but responding maintained by higher doses of cocaine was unaffected. Food-maintained behavior did not change during chronic treatment with modafinil. In a third study, after extinction of cocaine self-administration, modafinil (32 and 56 mg/kg/day, IV) significantly increased saline self-administration on the first day of treatment. These findings indicate that modafinil shares discriminative stimulus effects with cocaine and selectively reduces responding maintained by reinforcing doses of cocaine. These data are generally consistent with clinical findings and provide new evidence that these preclinical models may be useful for predicting the effectiveness of novel medications for drug abuse treatment
Early Quadriceps Strength Loss After Total Knee Arthroplasty : The Contributions of Muscle Atrophy and Failure of Voluntary Muscle Activation
While total knee arthroplasty reduces pain and provides a functional range of motion of the knee, quadriceps weakness and reduced functional capacity typically are still present one year after surgery. The purpose of the present investigation was to determine the role of failure of voluntary muscle activation and muscle atrophy in theearly loss of quadriceps strength after surgery
Total Knee Arthroplasty Assessments Should Include Strength and Performance-Based Functional Tests to Complement Range-of-Motion and Patient-Reported Outcome Measures
Range of motion (ROM) and pain often define successful recovery after total knee arthroplasty (TKA), but these routine clinical outcomes correlate poorly or not at all to functional capacity after TKA. The purpose of this Perspective is to underscore the importance of muscle strength and performance-based functional tests in addition to knee ROM and patient-reported outcome (PRO) measures to evaluate outcomes after TKA. Specifically: (1) muscle strength is the rate-limiting step for recovery of function after TKA; (2) progressive rehabilitation targeting early quadriceps muscle strengthening improves outcomes and does not compromise ROM after TKA; (3) ROM and PROs fail to fully capture functional limitations after TKA; and (4) performance-based functional tests are critical to evaluate function objectively after TKA. This Perspective also addresses studies that question the need for or benefit of physical therapy after TKA because their conclusions focus only on ROM and PRO measures. Future research is needed to determine the optimal timing, delivery, intensity, and content of physical therapy
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Operation Enduring Freedom: Foreign Pledges of Military and Intelligence Support
Gait Mechanics are Influenced by Quadriceps Strength, Age, and Sex after Total Knee Arthroplasty
Although most patients are satisfied with outcomes after total knee arthroplasty (TKA), many retain preoperative altered gait mechanics. Identifying patient characteristics associated with gait mechanics will improve rehabilitation strategies and enhance our understanding of movement disorders. Therefore, the purpose of this study was to identify which patient characteristics are related to gait mechanics in the surgical limb during walking post-TKA. Patient characteristics included age, body mass, sex, quadriceps strength, self-reported function, and knee pain. General linear regression was used to compare patient characteristics associated with gait mechanics, after controlling for gait speed, functional capacity and time from surgery. We tested 191 patients cross-sectionally at 6–24 months after primary, unilateral TKA. Quadriceps weakness in the surgical limb was associated with less peak vertical ground reaction force (PvGRF) (β = .245, p = .044), knee extension moment (β = .283, p = .049), and knee extension excursion (β = .298, p = .038). Older age (β = .168, p = .050) was associated with less PvGRF. Quadriceps strength in the nonsurgical limb (β = −.357, p = .021) was associated with greater knee extension excursion in the surgical limb. Females with TKA (β = −.276, p = .007) had less knee flexion excursion compared to males. Faster gait speed was also associated with greater PvGRF (β = .585, p \u3c .001), knee extensor moment (β = .481, p \u3c .001), and knee flexion excursion (β = .318, p \u3c .001). Statement of Clinical Significance: This study showed quadriceps weakness, slower gait speed, older age and being female were related to altered gait mechanics post-TKA. These findings will help clinicians better educate patients and develop targeted interventions for improving care in patients post-TKA
Resilience of a tropical sport fish population to a severe cold event varies across five estuaries in southern Florida
For species that are closely managed, understanding population resilience to environmental and anthropogenic disturbances (i.e., recovery trajectories across broad spatial areas) can guide which suite of management actions are available to mitigate any impacts. During January 2010, an extreme cold event in south Florida caused widespread mortality of common snook, Centropomus undecimalis, a popular sport fish. Interpretation of trends using fishery-independent monitoring data in five south Florida estuaries showed that changes in catch rates of adult snook (\u3e500 mm standard length) varied between no effects postevent to large effects and 4-yr recoveries. The reasons for the variation across estuaries are unknown, but are likely related to differences in estuary geomorphology and habitat availability (e.g., extent of deep rivers and canals) and differences in the proportions of behavior contingents (i.e., segments of the population that use divergent movement tactics) that place snook in different areas of the estuary during winter. Emerging awareness of the presence of behavior contingents, identification of overwintering sites, and improvements of abundance indices in remote nursery habitats should provide a better understanding of population resilience to disturbance events for snook. Given that changes in the frequency of short-lived, severe cold events are currently unknown, the findings and management actions described here for a tropical species living at the edge of its distribution should be useful to scientists forecasting the effects of climate change
Early quadriceps strength loss after total knee arthroplasty
Background: While total knee arthroplasty reduces pain and provides a functional range of motion of the knee,
quadriceps weakness and reduced functional capacity typically are still present one year after surgery. The purpose of
the present investigation was to determine the role of failure of voluntary muscle activation and muscle atrophy in the
early loss of quadriceps strength after surgery.
Methods: Twenty patients with unilateral knee osteoarthritis were tested an average of ten days before and twentyseven
days after primary total knee arthroplasty. Quadriceps strength and voluntary muscle activation were measured
with use of a burst-superimposition technique in which a supramaximal burst of electrical stimulation is superimposed
on a maximum voluntary isometric contraction. Maximal quadriceps cross-sectional area was assessed with
use of magnetic resonance imaging.
Results: Postoperatively, quadriceps strength was decreased by 62%, voluntary activation was decreased by 17%,
and maximal cross-sectional area was decreased by 10% in comparison with the preoperative values; these differences
were significant (p < 0.01). Collectively, failure of voluntary muscle activation and atrophy explained 85% of the
loss of quadriceps strength (p < 0.001). Multiple linear regression analysis revealed that failure of voluntary activation
contributed nearly twice as much as atrophy did to the loss of quadriceps strength. The severity of knee pain with
muscle contraction did not change significantly compared with the preoperative level (p = 0.31). Changes in knee
pain during strength-testing did not account for a significant amount of the change in voluntary activation (p = 0.14).
Conclusions: Patients who are managed with total knee arthroplasty have profound impairment of quadriceps
strength one month after surgery. This impairment is predominantly due to failure of voluntary muscle activation, and
it is also influenced, to a lesser degree, by muscle atrophy. Knee pain with muscle contraction played a surprisingly
small role in the reduction of muscle activation
Prospective Telehealth Analysis of Functional Performance, Frailty, Quality of Life, and Mental Health after COVID-19 hospitalization
Background
COVID-19 is a global pandemic with poorly understood long-term consequences. Determining the trajectory of recovery following COVID-19 hospitalization is critical for prioritizing care, allocating resources, facilitating prognosis, and informing rehabilitation. The purpose of this study was to prospectively evaluate recovery following COVID-19 hospitalization. Methods
Participants age 18 years or older who were hospitalized for ≥24 h due to COVID-19 completed phone/video call virtual assessments (including the 10-time chair rise test) and survey forms at three time points (2–6, 12, and 18 weeks) after hospital discharge. Univariate logistic and linear regression models assessed the associations of the outcomes with primary predictors (categorical age, sex, race/ethnicity group, and categorical pre-hospitalization frailty) at baseline; the same were used to assess differences in change from week 2–6 (continuous outcomes) or outcome persistence/worsening (categorical) at last contact. Results
One hundred nine adults (age 53.0 [standard deviation 13.1]; 53% female) participated including 43 (39%) age 60 or greater; 59% identified as an ethnic and/or racial minority. Over 18 weeks, the mean time to complete the 10-time chair rise test decreased (i.e., improved) by 6.0 s (95% CI: 4.1, 7.9 s; p \u3c 0.001); this change did not differ by pre-hospital frailty, race/ethnicity group, or sex, but those age ≥ 60 had greater improvement. At weeks 2–6, 67% of participants reported a worse Clinical Frailty Scale category compared to their pre-hospitalization level, whereas 42% reported a worse frailty score at 18 weeks. Participants who did not return to pre-hospitalization levels were more likely to be female, younger, and report a pre-hospitalization category of ‘very fit’ or ‘well’. Conclusions
We found that functional performance improved from weeks 2–6 to 18 weeks of follow-up; that incident clinical frailty developed in some individuals following COVID-19; and that age, sex, race/ethnicity, and pre-hospitalization frailty status may impact recovery from COVID-19. Notably, individuals age 60 and older were more likely than those under age 45 years to return to their pre-hospitalization status and to make greater improvements in functional performance. The results of the present study provide insight into the trajectory of recovery among a representative cohort of individuals hospitalized due to COVID-19. Background
Coronavirus disease (COVID)-19 is a global pandemic with poorly understood long-term consequences. Recent data suggest that even mild cases of COVID-19 can result in significant long-term morbidity [1]. Determining the trajectory of recovery in patients following COVID-19 hospitalization is critical for prioritizing care, allocating resources, facilitating prognosis, and informing rehabilitation
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Measuring the quality of inpatient specialist consultation in the intensive care unit: Nursing and family experiences of communication
Rationale: Critically ill patients in the intensive care unit (ICU) often require the care of specialist physicians for clinical or procedural expertise. The current state of communication between specialist physicians and families and nurses has not been explored. Objectives: To document the receipt of communication by nurses and family members regarding consultations performed on their patient or loved one, and to quantify how this impacts their overall perceptions of the quality of specialty care. Methods: Prospective survey of 60 adult family members and 90 nurses of 189 ICU patients who received a specialist consultation between March and October of 2015 in a single academic medical center in the United States. Surveys measured the prevalence of direct communication—defined as communication conducted in person, via telephone, or via text-page in which the specialist team gathered information about the patient from the nurse/family member and/or shared recommendations for care—and perceived quality of care. Results: In about two-thirds of family surveys (40/60) and one-half of nurse surveys (75/160), respondents had no direct communication with the specialist team that performed the consultation. Compared to nurses who had no direct communication with the specialists, those who did were 1.5 times more likely to rate the consultation as “excellent” (RR 1.48, 95% CI 1.2–1.8, p Conclusions: Most ICU families and nurses have no interaction with specialist providers. Nurses’ frequent exclusion from conversations about specialty care may pose safety risks and increase the likelihood of mixed messages for patients and families, most of whom desire some interaction with specialists. Future research is needed to identify effective mechanisms for information sharing that keep nurses and families aware of consultation requests, delivery, and outcomes without increasing the risk of mixed messages.</p
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