LLukas22/scidocs huggingface dataset:
Graph Coloring for class scheduling

The class scheduling problem can be modeled by a graph where the vertices and edges represent the courses and the common students, respectively. The problem is to assign the courses a given number of time slots (colors), where each time slot can be used for a given number of class rooms. The Vertex Coloring (VC) algorithm is a polynomial time algorithm which produces a conflict free solution using the least number of colors [9]. However, the VC solution may not be implementable because it uses a number of time slots that exceed the available ones with unbalanced use of class rooms. We propose a heuristic approach VC* to (1) promote uniform distribution of courses over the colors and to (2) balance course load for each time slot over the available class rooms. The performance function represents the percentage of students in all courses that could not be mapped to time slots or to class rooms. A randomized simulation of registration of four departments with up to 1200 students is used to evaluate the performance of proposed heuristic.
Exact Regenerating Codes for Distributed Storage

Erasure coding techniques are used to increase the reliability of distributed storage systems while minimizing storage overhead. The bandwidth required to repair the system after a node failure also plays a crucial role in the system performance. In [1] authors have shown that a tradeoff exists between storage and repair bandwidth. They also have introduced the scheme of regenerating codes which meet this tradeoff. In this paper, a scheme of Exact Regenerating Codes is introduced, which are regenerating codes with an additional property of regenerating back the same node upon failure. For the minimum bandwidth point, which is suitable for applications like distributed mail servers, explicit construction for exact regenerating codes is provided. A subspace approach is provided, using which the necessary and sufficient conditions for a linear code to be an exact regenerating code are derived. This leads to the uniqueness of our construction. For the minimum storage point which suits applications such as storage in peer-to-peer systems, an explicit construction of regenerating codes for certain suitable parameters is provided. This code supports variable number of nodes and can handle multiple simultaneous node failures. The constructions given for both the points require a low field size and have low complexity.
Environmental Science: A Global Concern, 5th edition

Sat, 16 Feb 2019 08:24:00 GMT environmental science a global concern pdf The environmental movement (sometimes referred to as the ecology movement), also including conservation and green politics, is a diverse scientific, social, and ... Sat, 16 Feb 2019 11:37:00 GMT Environmental movement Wikipedia Environmental Effects of Increased Atmospheric Carbon Dioxide, Links, Authorship, and Address, ABSTRACT, SUMMARY, ATMOSPHE A SURFAC TEMPERATURES, ATMOSPHE CARB ... Tue, 29 Jan 2019 18:32:00 GMT Environmental Effects of Increased Atmospheric Carbon ... This is a glossary of environmental science. Environmental science is the study of interactions among physical, chemical, and biological components of the environment. Sun, 17 Feb 2019 05:59:00 GMT Glossary of environmental science Wikipedia Science information about stratospheric ozone layer protecting humans and earth from ultraviolet (UV) rays Sat, 16 Feb 2019 15:33:00 GMT Ozone Layer Protection | US EPA IPIECA develops, shares and promotes good practice and knowledge to help the oil and gas industry improve its environmental and social performance. Mon, 04 Feb 2019 20:12:00 GMT The global oil and gas industry association for ... National Institute of Environmental Health Sciences | The mission of the NIEHS is to discover how the environment affects people in order to promote healthier lives Sun, 17 Feb 2019 03:58:00 GMT National Institute of Environmental Health Sciences (NIEHS) This website provides easy access to all the pesticide-related information that is contained in various pesticide topical sites. It also includes news and meeting ... Sun, 17 Feb 2019 11:43:00 GMT Pesticides | US EPA Climate and environmental science denial: A review of the scientific literature published in 1990â€“2015 Fri, 15 Feb 2019 16:25:00 GMT Climate and environmental science denial: A review of the ... What is Environmental Security? The relation between the environment and the security of humans and nature has been the object of much research and the subject of ... Thu, 02 Dec 2004 23:59:00 GMT What is Environmental Security Scientific Partnerships for a Healthier World International Life Sciences Institute ILSI is a nonprofit, worldwide organization whose mission is to provide science ... Fri, 08 Feb 2019 05:34:00 GMT ILSI | Global Partnerships for a Healthier World Vital Signs of the Planet: Global Climate Change and Global Warming. Partial list of leading scientific organizations endorsing human-induced climate change, along ... Thu, 14 Feb 2019 22:02:00 GMT Scientific Consensus | Facts â€“ Climate Change: Vital Signs ... We examine whether conservative white males are more likely than are other adults in the U.S. general public to endorse climate change denial. Cool dudes: The denial of climate change among ... Page 3 of 18 Joshi & Ahmed, Cogent Environmental Science (2016), 2: 1139434 http://dx.doi.org/10.1080/23 311843.2016.1139434 2.2. Generation and collection Status and challenges of municipal solid waste management ... -
The effect of fasting on erectile function and sexual desire on men in the month of Ramadan.

PURPOSE
To determine the effect of Ramadan intermittent fasting on erectile function (EF), sexual desire and serum hormone levels.


MATERIALS AND METHODS
Eligible male participants completed the two domains of International Index of Erectile Function (IIEF) questionnaire for EF and sexual desire. They also provided information on any known disease, treatment taking, smoking habits and frequency of sexual intercourse. Frequency of sexual intercourse, two domains of IIEF questionnaire, serum hormone levels, body weight before and four-weeks after the end of month of Ramadan were also recorded.


RESULTS
Overall, 45 men, with a mean age of 37 ± 7.2 years, participated in the study. Frequency of sexual intercourse (P = .046), sexual desire (P = .002), body weight (P = .009) and serum follicle stimulating hormone (FSH) level (P = .016) decreased significantly at the end of month of Ramadan compared to baseline. No statistically significant differences were found on EF (P = .714), serum testosterone (P = .847), luteinizing hormone (P = .876), estradiol (P = .098) and dehydroepiandrosterone sulfate levels (P = .290).


CONCLUSION
Ramadan intermittent fasting might be associated with decrease in sexual desire, frequency of sexual intercourse and serum FSH level.
Tenofovir Gel for the Prevention of Herpes Simplex Virus Type 2 Infection.

BACKGROUND
Globally, herpes simplex virus type 2 (HSV-2) infection is the most common cause of genital ulcer disease. Effective prevention strategies for HSV-2 infection are needed to achieve the goals of the World Health Organization global strategy for the prevention and control of sexually transmitted infections.


METHODS
We assessed the effectiveness of pericoital tenofovir gel, an antiviral microbicide, in preventing HSV-2 acquisition in a subgroup of 422 HSV-2-negative women enrolled in the Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004 study, a double-blind, randomized, placebo-controlled trial. Incident HSV-2 cases were identified by evidence of seroconversion on an HSV-2 IgG enzyme-linked immunosorbent assay between study enrollment and exit. A confirmatory analysis was performed by Western blot testing.


RESULTS
The HSV-2 incidence rate was 10.2 cases per 100 person-years (95% confidence interval [CI], 6.8 to 14.7) among 202 women assigned to tenofovir gel, as compared with 21.0 cases per 100 person-years (95% CI, 16.0 to 27.2) among 222 women assigned to placebo gel (incidence rate ratio, 0.49; 95% CI, 0.30 to 0.77; P=0.003). The HSV-2 incidence rate among the 25 women with vaginal tenofovir concentrations of 10,000 ng per milliliter or more was 5.7 cases per 100 person-years, as compared with 15.5 cases per 100 person-years among the 103 women with no detectable vaginal tenofovir (incidence rate ratio, 0.37; 95% CI, 0.04 to 1.51; P=0.14). As confirmed by Western blot testing, there were 16 HSV-2 seroconversions among women assigned to tenofovir gel as compared with 36 among those assigned to the placebo gel (incidence rate ratio, 0.45; 95% CI, 0.23 to 0.82; P=0.005).


CONCLUSIONS
In this study in South Africa, pericoital application of tenofovir gel reduced HSV-2 acquisition in women. (Funded by the U.S. Agency for International Development and others; ClinicalTrials.gov number, NCT00441298.).
Effects of stimulating hip and trunk muscles on seated stability, posture, and reach after spinal cord injury.

OBJECTIVE
To determine the stimulated strength of the paralyzed gluteal and paraspinal muscles and their effects on the seated function of individuals with paralysis.


DESIGN
Case series with subjects acting as their own concurrent controls.


SETTING
Hospital-based clinical biomechanics laboratory.


PARTICIPANTS
Users (N=8) of implanted neuroprostheses for lower extremity function with low-cervical or thoracic level injuries.


INTERVENTIONS
Dynamometry and digital motion capture both with and without stimulation to the hip and trunk muscles.


MAIN OUTCOME MEASURES
Isometric trunk extension moment at 0°, 15°, and 30° of flexion; seated stability in terms of simulated isokinetic rowing; pelvic tilt, shoulder height, loaded and unloaded bimanual reaching to different heights, and subjective ratings of difficulty during unsupported sitting.


RESULTS
Stimulation produced significant increases in mean trunk extension moment (9.2±9.5Nm, P<.001) and rowing force (27.4±23.1N, P<.012) over baseline volitional values. Similarly, stimulation induced positive changes in average pelvic tilt (16.7±15.7°) and shoulder height (2.2±2.5cm) during quiet sitting and bimanual reaching, and increased mean reach distance (5.5±6.6cm) over all subjects, target heights, and loading conditions. Subjects consistently rated tasks with stimulation easier than voluntary effort alone.


CONCLUSIONS
In spite of considerable intersubject variability, stabilizing the paralyzed trunk with electrical stimulation can positively impact seated posture, extend forward reach, and allow exertion of larger forces on objects in the environment.
Telephone counseling and attendance in a national mammography-screening program a randomized controlled trial.

BACKGROUND
In Germany, a mammography-screening program (MSP) was implemented on a national level. It complies with all criteria of the European guidelines for quality assurance in screening mammography; however, the attendance rate is 54%, falling short of the target attendance rate of 70%. The aim of this study was to investigate whether additional telephone counseling improves attendance among nonresponders and the level of satisfaction with telephone counseling.


DESIGN
In a prospective RCT, women identified as nonresponders in the MSP were randomized to a control group that received written reminders or to an intervention group that additionally received telephone counseling. In a follow-up, a subset of the intervention group was contacted by telephone regarding their satisfaction with telephone counseling.


SETTING/PARTICIPANTS
In 2008, a total of 5477 women aged 50-69 years who were eligible for the German MSP but had not participated up to 6 weeks after the first invitation were included in the study.


INTERVENTIONS
Individual telephone counseling consisted of scripted calls from a trained counselor who provided information on MSP and answered the woman's questions.


MAIN OUTCOME MEASURES
Report of mammography use provided by the screening unit 3 months after the reminder was sent.


RESULTS
Analysis was conducted in 2009. Comparison of screening attendance revealed a significantly higher attendance rate in the intervention group compared with controls (29.7% vs 26.1%, p=0.0035). When only women for whom telephone numbers were available were analyzed, attendance was even better (35.5% vs 29.7%, p=0.0004). In the follow-up, 278 of 404 women were actually surveyed. Of those, 33% stated that telephone counseling had influenced their decision, 56% stated that they had undergone screening mammography, and 77% agreed that personal telephone counseling should be used routinely to encourage nonresponders to go for screening.


CONCLUSIONS
Individual telephone counseling for nonresponders to a national program for breast cancer screening was well accepted by participants and effective.


TRIAL REGISTRATION
This study is registered at the Australian New Zealand Clinical Trials Registry ACTRN12611000645954.
Rigid versus flexible dentine-like endodontic posts--clinical testing of a biomechanical concept: seven-year results of a randomized controlled clinical pilot trial on endodontically treated abutment teeth with severe hard tissue loss.

INTRODUCTION
This is the first clinical long-term pilot study that tested the biomimetic concept of using more flexible, dentine-like (low Young modulus) glass fiber-reinforced epoxy resin posts (GFREPs) compared with rather rigid, stiff (higher Young modulus) titanium posts (TPs) in order to improve the survival rate of severely damaged endodontically treated teeth.


METHODS
Ninety-one subjects in need of postendodontic restorations in teeth with 2 or less remaining cavity walls were randomly assigned to receive either a tapered TP (n = 46) or a tapered GFREP (n = 45). The posts were adhesively luted using self-adhesive resin cement. The composite core build-ups were prepared ensuring a circumferential 2-mm ferrule. The primary endpoint was a loss of restoration for any reason. To study group differences, the log-rank test was calculated (P < .05). Hazard plots were constructed.


RESULTS
After 84 months of observation (mean = 71.2 months), 7 restorations failed (ie, 4 GFREPs and 3 TPs). The failure modes were as follows: GFREP:root fracture (n = 3), core fracture (n = 1) and TP:endodontic failure (n = 3). No statistical difference was found between the survival rates (GFREPs = 90.2%, TPs = 93.5%, P = .642). The probability of no failure was comparable for both post materials (risk ratio; 95% confidence interval, 0.965-0.851/1.095).


CONCLUSIONS
When using self-adhesive luted prefabricated posts in severely destroyed abutment teeth with 2 or less cavity walls and a 2-mm ferrule, postendodontic restorations achieved high long-term survival rates irrespective of the post material used (ie, glass fiber vs titanium).
Open Universes from Bubbles: An Introduction and Update

An introduction to models of open universes originating from bubbles, including a summary of recent theoretical results for the power spectrum. To appear in the proceedings of the XXXIth Moriond meeting, "Microwave Background Anisotropies."
Changes in the small bowel of symptomatic kidney transplant recipients converted from mycophenolate mofetil to enteric-coated mycophenolate sodium.

BACKGROUND/AIMS
Gastrointestinal (GI) symptoms in renal transplant recipients may be caused due to mycophenolic acid (MPA) toxicity. Using small bowel capsule endoscopy (SBCE) we examined the impact of conversion from Mycophenolate Mofetil (MMF) to enteric-coated formulation of Mycophenolate Sodium (EC-MPS) given to treat GI mucosal lesions.


METHODS
Adult kidney-only recipients at least 30 days after transplant, presenting with GI symptoms while receiving MMF completed a Gastrointestinal Symptom Rating Scale (GSRS) questionnaire, underwent SBCE, and had MMF substituted by EC-MPS. After 30 days, GSRS and SBCE were repeated and findings were compared to baseline values. Patients who were still on EC-MPS 6-24 months post-conversion were contacted for completing a follow-up GSRS questionnaire and SBCE.


RESULTS
Eighteen out of 23 subjects completed the first part of the study. Subjects' median ages and post-transplant time were 47.5 years old and 4.5 months, respectively. Tacrolimus, MMF and prednisone was the main regimen (94%), with a median MMF dose of 750 mg BID. The average baseline GSRS was 2.99 ± 0.81; it significantly decreased to 2.19 ± 0.8 at 30 days post-conversion. At baseline, 50 had gastric and 89% had small bowel lesions. At 30 days, 29 and 62% of the SBCE were still showing gastric and small bowel lesions, respectively. Of 5 patients in the study extension, 4 had abnormal SBCE findings but have been reporting improvement in their symptoms.


CONCLUSION
Stomach and small bowel mucosal lesions are common in kidney recipients with GI symptoms when treated with MMF. Conversion to EC-MPS for 30 days significantly alleviated the GI symptoms; however, no evident correlation with SBCE findings was found.
Physico-chemical properties and heavy metal content of water sources in Ife North Local Government Area of Osun State, Nigeria

The water quality examination in Ife–North Local Government of Osun State Nigeria was conducted by determining the physico–chemical parameters of 40 samples. Surface water, bore holes, wells and pipe borne water samples were collected from major towns in the Local Government Area and analyzed. Results showed temperature range of 26.5 to 33.0°C, pH (6.53 to 8.90), conductivity (63.0 to 1039.0 μS/cm), resistivity (0.00 to 0.02m .cm), salinity (300.00 to 700.00 mg/L), total solids (90.00 to 1175.00 mg/L), total dissolved solids (37.80–622.50mg/l), suspended solids (34.50 to 794.00 mg/L),dissolved oxygen (4.48 to 9.48 mg/L), Biological Oxygen Demand (BOD5) (0.69 to 6.74 mg/L), chloride (3.64 to 184.04mg/L), Nitrate (1.08 to 53.03 mg/L), phosphate (4.99 to 23.07 mg/L) and sulphate (6.02 to 28.95 mg/L). Results of Atomic Absorption spectrophotometric analysis (AAS) of samples for dissolved trace metals; (Cd, Pb, Mn, Zn, Cu, Cr and Fe), showed mean metal concentration to vary widely depending on the source of the water sample as follows: Pb (0.29 ± 0.05 to 6.69 ± 0.53 mg/L), Cd (0.77 ± 0.06 to 2.24 ± 0.08 mg/L), Zn (0.03 ± 2.15 to 0.22 ± 4.64 mg/L), Cu ( 0.18 ± 16.34 to 0.41 ± 5.00 mg/L), Fe (6.00 ± 0.21 to 31.75 ± 0.80mg/L) and Mn (0.14 ± 6.12 to 0.23 ± 99.11 mg/L). The results obtained for the physical parameters agreed with the limits set by both national and international bodies for drinking and domestic water with few exceptions.
SOFTWARE CONSIDERATIONS IN AIRBORNE SYSTEMS AND EQUIPMENT CERTIFICATION

R euse has been defined variously: Definitions range from " the systematic practice of developing software from a stock of building blocks, so that similarities in requirements and/or architecture between applications can be exploited to achieve substantial benefits in productivity , quality, and business performance " [1] to " the process of creating software systems from predefined software components " [2]. The first definition is seemingly more complete, but the second definition is less restrictive and more useful. Too often in literature, a purist attitude is taken toward reuse. For example, often the term reuse is applied to only those elements that can be used without change or to only those elements that have been designed and configured for reuse. For this article, therefore , reuse is defined simply as using previously existing software artifacts. Artifacts include all products of a certification development process and include plan-Reuse Factors Functional Alignment Two aspects of functional alignment can affect the reuse strategy adopted. The first aspect, applicability, is a determination of how well the existing require-ments/functionality align with the requirements of the target application. Do the artifacts serve the intended pur-pose? How much must the artifacts be modified to accommodate any new func-tionality? The second aspect also concerns the alignment of new functionality to existing functionality, although in the opposite respect. Does the existing configuration contain more functionality than is needed for the targeted application? What must be done to accommodate this additional functionality? The issues surrounding extra func-tionality are prevalent with design-for-reuse component libraries. These libraries are designed to include all possible future functionality needs and, by their very nature, include additional func-tionality. These existing configurations typically contain more functionality than is needed for the targeted application. How, then, must this additional functionality be accommodated in a certifiable software system? A variety of strategies are available to handle extra functionality. Seemingly, the most simple is to strip the unnecessary functionality from the configuration (from requirements through verification arti-facts). Conceptually, this is the simplest approach, but this may not be the most cost-effective approach. Additional unused functionality may be retained in the code as long as the mechanism by which such code could be inadvertently executed is prevented, isolated , or eliminated [3] is verified. In other words, although the code is present, its non-availability within a specific application must be demonstrated. Typically, this means that the unused functional interface must be …
Retrospective survival analysis of 110 lithium disilicate crowns with feather-edge marginal preparation.

PURPOSE
To evaluate the clinical performance of lithium disilicate (LiDiSi) crowns with a feather-edge finish line margin over a 9-year period.


MATERIALS AND METHODS
In total, 110 lithium disilicate crowns, 40 anterior (36.3%) and 70 posterior (63.7%), were cemented with resin cement after fluoridric acid and silane surface treatment and observed by a different clinician. The data were analyzed using the Kaplan-Meier method. The clinical evaluation used the California Dental Association (CDA) modified criteria after recalling all patients between January and April 2013.


RESULTS
Two crowns had failed and were replaced due to core fractures. One chipping occurred on a first molar and the ceramic surface was polished. The overall survival probability was 96.1% up to 9 years, with a failure rate of 1.8%.


CONCLUSION
In this retrospective analysis, lithium disilicate with a vertical finish line used in single-crown restorations had a low clinical failure rate up to 9 years.