Miracle-dz/UniFAR-FTUs huggingface dataset:
Conformational Spread as a Mechanism for Cooperativity in the Bacterial Flagellar Switch

Complex Cooperativity Cooperativity in multisubunit protein complexes is classically understood in terms of either a concerted model, in which all subunits switch conformation simultaneously, or a sequential model, in which a subunit switches conformation whenever a ligand binds. More recently, a “conformational spread” model has suggested that a conformational coupling between subunits and between subunit and ligand is probabilistic. Using high-resolution optical microscopy, Bai et al. (p. 685; see the Perspective by Hilser) observed multistate switching of the bacterial flagellar switch complex that was previously understood in terms of a concerted allosteric model. The conformational spread model gives quantitative agreement with the data. The behavior of the bacterial flagellar switch is modeled by probabilistic conformational coupling of the protein. The bacterial flagellar switch that controls the direction of flagellar rotation during chemotaxis has a highly cooperative response. This has previously been understood in terms of the classic two-state, concerted model of allosteric regulation. Here, we used high-resolution optical microscopy to observe switching of single motors and uncover the stochastic multistate nature of the switch. Our observations are in detailed quantitative agreement with a recent general model of allosteric cooperativity that exhibits conformational spread—the stochastic growth and shrinkage of domains of adjacent subunits sharing a particular conformational state. We expect that conformational spread will be important in explaining cooperativity in other large signaling complexes.
A New Peroneal Tendon Rerouting Method to Treat Recurrent Dislocation of Peroneal Tendons

Background The surgical treatment methods for recurrent dislocation of peroneal tendons are controversial. A simpler and more effective treatment method is valuable for these patients. Hypothesis A new rerouting operation designed by the authors will have satisfactory results and avoid disadvantages of the old rerouting methods. Study Design Case series; Level of evidence, 4. Methods Seventeen consecutive male patients with unilateral recurrent peroneal tendon dislocations were treated by transposition of the calcaneofibular ligament from the tubercle of calcaneofibular ligament with a 1 × 1 × 1 cm3 bone block and elevation of this tubercle with another 1 × 1 × 1 cm3 calcaneal bone block, which were fixed by a 3.5-mm cancellous screw with a washer. All patients received clinical and radiographic follow-up for at least 2 years. The preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scales were used for functional results assessment. Results All bone transposition sites healed radiographically at 6 weeks after surgery. Four patients had transient numbness over the lateral aspect of the injured foot, and 3 patients had swelling and pain involving the operative sites. All complications resolved by 3 to 5 months after the operation. No recurrent dislocation of the peroneal tendons was noted. The mean AOFAS ankle-hindfoot scale improved significantly, from 73.4 ± 5.5 preoperatively to 100 at 2- to 5-year follow-up (P <. 001). Normal ankle stability and no tightening of the lateral side of the injured ankles in the inversion position were noted. Conclusion This method is a simple, reliable, and reproducible operation to treat recurrent dislocation of the peroneal tendons. It allows early return to daily, working, and sports activities with satisfactory results.
Measurement factors model for e-learning systems success

Information Systems (IS) implementation in higher education is a large investment. Such investments are expected to bring increased efficiency and effectiveness, as well as better quality services to stakeholders. E-learning is one of the recent trends and major technological advancements in Information Technology (IT), reshaping the mode of delivery of education in universities. To effectively and efficiently evaluate the success of an e-learning system, success measurement factors must be identified and measured for any university that implements e-learning systems. This study explores and develops measurement factors model for e-learning systems success in Ethiopian higher Level Education Institutes (EHEIs). Both qualitative and quantitative research methodologies are used to perform the study. The study is based on the Information System Success (ISS) model and extends the model to investigate e-learning systems success measurement factors in developing countries such as Ethiopia. Our literature search did not find any study that examines the complete IS success model in order to identify measurement factors of e-learning systems success in Ethiopia that should be of value to higher learning institutions' management, e-learning systems designers and providers, and instructors when planning and implementing e-learning projects.
Stress in Nursing Home Staff: A Review and a Theoretical Model

Although many aspects of occupational stress have been investigated individually, few studies have successfully integrated different characteristics of stress. Moreover, little attention has been focused on staff stress in nursing homes. This article examines the literature on occupational stress in nursing staff and offers a comprehensive model of long-term nursing care stress. The literature review shows that a large number offactors affect occupational stress,from workplace issues such as institutional policies and residents' disabilities to the personal lives of the nursing staff. The stress in turn causes work dissatisfaction, followed by staff intent to leave, resulting in increased turnover. Staff stress also affects the individual worker in many ways. The model encompasses the antecedents, responses, and consequences of stress for individuals in an organization. The outcome variables affect the initial sources of stress and resources both at the job and at the personal levels, producing a cyclic process.
Minimum 10-Year Results after Anterior Cruciate Ligament Reconstruction

Background Few long-term studies exist that evaluate how the loss of normal knee range of motion affects results after anterior cruciate ligament reconstruction. Hypothesis Patients with normal knee motion will have higher subjective scores than patients with less than normal motion. Study Design Cohort study; Level of evidence, 2. Methods Patients were prospectively evaluated at > 10 years after anterior cruciate ligament reconstruction according to International Knee Documentation Committee criteria. Normal knee motion was within 2° of extension (including hyperextension) and 5° of flexion compared with the uninvolved knee. Regression analysis was performed to determine what factors affected subjective scores. Results Objective follow-up was obtained on 502 patients at a mean of 14.1 years postoperatively. Regression analysis showed that the most statistically significant factor related to lower subjective scores was lack of normal knee extension; loss of normal flexion was also significant. Patients who had meniscectomy or articular cartilage damage had statistically significantly lower subjective scores if they also had less than normal motion. Ninety-eight percent of patients with intact menisci, normal articular cartilage, and normal knee motion had normal radiographs; 29% of patients with normal motion had less than normal radiographs versus 71% of patients who had less than normal motion. The overall International Knee Documentation Committee objective grade was normal in 48%, nearly normal in 42%, abnormal in 9%, and severely abnormal in 0.5%. Conclusion The loss of 3° to 5° of knee extension, to include loss of hyperextension, adversely affected the subjective and objective results after surgery, especially when coupled with meniscectomy and articular cartilage damage.
Histopatologia da leishmaniose tegumentar por Leishmania braziliensis braziliensis: 4. Classificação histopatológica

The Authors have analysed the histopathological alterations observed in 162 cases of Mucocutaneous Leishmaniasis from Tres Bracos, Bahia, of whom 131 (80,9%) had purely cutaneous lesions and 31 (19,1%) had only mucosal lesions. The clinical behavior of 5 histopathological forms was documented in relation to treatment. The best prognosis was associated with the exudative granulomatous histopathology, a phase where the a host mechanism to use the parasite is evident leading to necrosis and granuloma formation as a residual sign. Therapy in this phase merely hastened the process. In a further large group the lesions were classified as exudative cellular reaction (cutaneous forms), an exudative necrotic reaction and an exudative necrotic gra- nulomatous reaction. In these cases the mechanisms of host defense are still being developed and the effect of therapy is to reduce the time to healing. Cutaneous cases with an exudative tuberculoid reaction had a worse prognosis, although there was a favourable response to treatment if the patient was young, the lesion was of short duration and the intradermal leishmanin test was not exaggerated Lastly are a group of mucosal cases with an exudative cellular reaction where this infiltrate may be a manifestation of auto agression. These cases, also classified as exudative tuberculoid, occur in adult patients with longstanding lesions and an exaggerated leishmanin skin test. They have a poor prognosis. This study develops suggestions for a classification based on the histopathological picture which could be valuable in predicting prognosis and influencing the choice of treatment. This classification is strictly morphological and is easy for the pathologist to apply. It appears to, correspond to the clinical course of the illness and could aid the clinician in the initial case evaluation.
Sports and Recreation Activity of Patients with Femoroacetabular Impingement before and after Arthroscopic Osteoplasty

Background Hip arthroscopy represents a new and minimally invasive method of treating patients with femoroacetabular impingement (FAI). However, participation in popular sports after this procedure has not yet been analyzed. Hypotheses Arthroscopic treatment of FAI increases the level of popular sports activities, and this level of activity correlates with the clinical outcome in terms of pain and function. Study Design Case series; Level of evidence, 4. Methods Fifty-three patients (41 male, 12 female) were evaluated preoperatively and after a mean follow-up of 2.4 years (range, 2-3.2 years) after arthroscopic osteoplasty for cam and mixed FAI. Evaluation included the type and level of sports activities (sports frequency score [SFS]) as well as clinical outcome in terms of pain (VAS) and function (nonarthritic hip score [NAHS]). Results Forty-five of the 53 patients had regularly participated in popular sports until the first occurrence of FAI symptoms. Preoperatively, only 4 of these 45 patients had maintained their accustomed level of activity. At the final follow-up, 31 patients had returned to their full accustomed level of activity. None of the patients who had not been active in sports before the first occurrence of symptoms of FAI (n = 8) had begun participation in sports after arthroscopic osteoplasty. The SFS significantly increased from 0.78 to 1.84 (P < .001), and the mean VAS pain score significantly improved from 5.7 (range, 1-9) to 1.5 (range, 0-6) points (P < .001). The NAHS improved from 54.4 (range, 28.75-92.5) to 85.7 (range, 47.5-100) (P < .001). There was no significant correlation between SFS and NAHS (r = .051, P = .35), as well as between SFS and VAS pain score (r = .159, P = .140) preoperatively, but a significant correlation was seen at the time of the last postoperative follow-up (SFS/NAHS: r = .392, P = .003; SFS/VAS: r = .242, P = .049). The 3 most frequent sports activities postoperatively were biking, hiking, and fitness. Conclusion Arthroscopic osteoplasty can significantly improve the rate and level of popular sports activities in patients with FAI. The level of postoperative sports activity directly correlates with the clinical outcome in terms of pain and function.
MIT OpenCourseWare: Unlocking Knowledge, Empowering Minds

A collection of more than 2000 course syllabi, lecture notes, assignments, and exams is provided free of charge. As the global economy increasingly demands an educated workforce, school systems in the United States and abroad find themselves overwhelmed by student demand. Particularly in the developing world, there are not enough seats in classrooms with qualified teachers to make high-quality education opportunities available to every student. In places ranging from China to India to Turkey, only a small percentage of qualified students are accepted into university programs, especially those in science and technology fields. Existing institutions are under enormous pressure, and the needs of talented and motivated learners are not being met. Making headway against these formidable challenges will require rethinking traditional educational approaches and will call for the use of innovative technologies to scale up global capacity for providing high-quality education.
Slip in the 1857 and Earlier Large Earthquakes Along the Carrizo Plain, San Andreas Fault

Slip, Tripped, and Faulted Earthquake risk assessment can be improved if we were able to quantify the recurrence and magnitude of slip events. Until recently though, a lack of sophisticated seismometers has forced us to rely on anecdotal evidence from those who survived major earthquakes or to look for clues in the landscape. Zielke et al. (p. 1119, published online 21 January; see the Perspective by Scharer) analyzed high-resolution images of the San Andreas Fault in southern California. The data showed that major surface ruptures, such as the 1857 Fort Tejon earthquake, resulted from slips of only about 5 meters; much less than previously thought. In a study that lends support to this discovery, Grant Ludwig et al. (p. 1117, published online 21 January; see the Perspective by Scharer) suggest from analysis of the geomorphic features of this region that several smaller earthquakes have occurred during recent centuries rather than infrequent but larger movements. The Perspective by Scharer (p. 1089) discusses how paleoseismological studies like these may be valuable for feeding data into earthquake prediction. The historical behavior of the San Andreas Fault may have been dominated by smaller, more frequent slip events. The moment magnitude (Mw) 7.9 Fort Tejon earthquake of 1857, with a ~350-kilometer-long surface rupture, was the most recent major earthquake along the south-central San Andreas Fault, California. Based on previous measurements of its surface slip distribution, rupture along the ~60-kilometer-long Carrizo segment was thought to control the recurrence of 1857-like earthquakes. New high-resolution topographic data show that the average slip along the Carrizo segment during the 1857 event was 5.3 ± 1.4 meters, eliminating the core assumption for a linkage between Carrizo segment rupture and recurrence of major earthquakes along the south-central San Andreas Fault. Earthquake slip along the Carrizo segment may recur in earthquake clusters with cumulative slip of ~5 meters.
Valuing Common Species

Ecologically common species play key roles in terrestrial and marine ecosystems, yet are also the main victims of habitat loss, ecosystem degradation, and overexploitation. Aldo Leopold's dictum that “To keep every cog and wheel is the first precaution of intelligent tinkering” (1) has been oft repeated in the context of environmental management. The argument is beguilingly simple. In the absence of a detailed understanding of what each species does in an ecosystem, it would be foolish to allow the loss of any one of them. It is the precautionary principle writ large and, given its enormous ramifications for the ways in which people interact with the natural world, ecologists have spent much intellectual energy, time, and resources in determining whether it has a strong empirical basis (2). Indeed, some of the best-known recent ecological experiments have examined the consequences of varying the numbers of species in a small area on ecosystem function. This focus assumes that the importance of retaining Leopold's cogs and wheels lies mostly in the differences between them. However, a growing body of work on common species underlines that having sufficient copies of some key pieces may be equally, and perhaps often more, important.
Marginal Notes on Amethodical Requirements Engineering:  What Experts Learned from Experience

Requirements engineers with many years of experience have a distinct perspective on the field. To sample this knowledge, we interviewed 34 requirements researchers and practitioners, each with up to 42 years of experience. We used open-ended, structured interviews in which we asked them to reflect on their experiences and professional development as requirements engineers over their careers. Several themes emerged: requirements engineers act as bridges between different worlds, good communication is key, good process can help but isn't everything, shorter requirements documents can be better, and good requirements are driven by customer value not technical elegance. All of these pertain to amethodical requirements engineering. Amethodical concepts are not rejections of method, but rather those concepts that are marginalized and left out of prescriptive methods for carrying out a procedure. We discuss these results and their implications.
The effect of alcoholism on secretor status of blood groups A and B individuals in Jos – Nigeria

The ability to secrete blood group A and B substances in the saliva of individuals has been studied in alcoholics. Individuals who secrete their corresponding ABH substances in body fluids are known as secretors, while those who do not secrete these substances are non-secretors. Three hundred people were tested. One hundred and fifty were alcoholics and one hundred and fifty non-alcoholics served as controls. In the alcoholic group, seventy five were blood group B while seventy five were blood group A. Fifty out of the seventy five (67%) group A alcoholics were secretors, while 25 (33%) were non-secretors. Fourty two out of the seventy five (56%) blood group B alcoholics were secretors, while thirty three (44%) were non-secretors. In the non-alcoholic group, seventy five were of blood group A while the other seventy five had blood group B. Fifty eight out of the seventy five (77%) group A non-alcoholics were secretors while seventeen (23%) were non-secretors. Sixty three out of the seventy five (84%) blood group B non-alcoholics were secretors while 12 (16%) were non-secretors. The results show that the non-secretor status among the alcoholics (39%) was higher than the 19% for non-alcoholics. This would suggest that alcohol drastically alters ABH secretor blood group status of individuals. There was a significant difference (P Keywords : alcoholism, secretor status, blood group Journal of Medicine in the Tropics Vol. 7(2) 2005: 8-12
A 7-Year Prospective, Randomized, Clinical, and Radiographic Study After Arthroscopic Bankart Reconstruction Using 2 Different Types of Absorbable Tack

Background Recent studies have shown that techniques for arthroscopic Bankart reconstruction using suture anchors or tacks can equal the results after an open procedure in the treatment of posttraumatic, recurrent, unidirectional shoulder instability. Which kind of technique and which implants to be used still need further study. Purpose The aim of this study was to compare the clinical and radiographic results after arthroscopic Bankart reconstruction using 2 different types of absorbable implants. Study Design Randomized controlled trial; Level of evidence, 1. Methods A randomized series of 40 patients who had recurrent shoulder instability underwent reconstruction involving either polygluconate-B polymer or self-reinforced poly-L-lactic acid polymer tack implants. The patients underwent radiographic and clinical assessments preoperatively and at 7 years. Blood levels of C-reactive protein were analyzed preoperatively and postoperatively. Results The radiographic visibility of the drill holes was significantly (P = .0001) greater in the poly-L-lactic acid polymer group than in the polygluconate-B polymer group. The failure rate in terms of stability was 5 of 36 (14%) after 7 years and, as previously reported by Magnusson et al, 2 of 40 (5%) after 2 years. Analyses preoperatively and postoperatively of C-reactive protein revealed no significant difference between the groups. No significant differences were found between the groups in terms of strength in abduction, range of motion, and Rowe or Constant scores. Conclusion Seven years after Bankart repair using either implant, the overall clinical results were satisfactory. The visibility of the drill holes was significantly greater after using poly-L-lactic acid polymer implants.
Activity Level and Graft Type as Risk Factors for Anterior Cruciate Ligament Graft Failure

Background Anterior cruciate ligament (ACL) graft failure is an uncommon but devastating event after reconstruction, and risk factors for graft failure are not well understood. Hypothesis Returning to a high activity level after ACL reconstruction and use of an allograft are risk factors for ACL graft failure. Study Design Case-control study; Level of evidence, 3. Methods Twenty-one patients with ACL graft failure were identified over a 2-year period. Forty-two age- and sex-matched controls were identified over the same period. A 1:2 matched case-control design was used to evaluate activity level after reconstruction and graft type as risk factors for ACL graft failure. Logistic regression analysis was used to determine odds ratios for activity level after reconstruction and for graft type among cases and controls. Association (interaction) between activity level after reconstruction and graft type was evaluated comparing stratum-specific odds ratios. Results Univariate logistic regression models showed an increased odds of ACL graft failure for those with high activity level compared with low activity level (odds ratio [OR], 5.53; 95% confidence interval [CI], 1.18–28.61; P = .03) and for allografts compared with autografts (OR, 5.56; 95% CI 1.55–19.98; P = .009). A bivariate logistic regression model showed a 35% change in the odds ratio for activity level (OR, 4.33; 95% CI, 0.89–21.16; P = .07) and a 13% change in the odds ratio for allograft compared with autograft (OR, 4.93; 95% CI, 1.34–18.20; P = .02). Stratum-specific odds ratios between activity level and graft type show a multiplicative interaction between higher activity level and allograft for much greater odds of ACL graft failure. Conclusion Higher activity level after reconstruction and allograft use for reconstruction are risk factors for ACL graft failure. Stratum-specific odds ratios show a multiplicative interaction between higher activity level after ACL reconstruction and allograft use, greatly increasing the odds for ACL graft failure.