cssi/SciSciGPT-SciSciNet huggingface dataset:
NOT ALL CEMENTLESS STEMS ARE CREATED EQUAL: A SELECTION ALGORITHM

Three basic design concepts of cementless femoral fixation have emerged. They include: anatomic designs, straight stem designs, and tapered designs. In addition, there have been modular designs. The most successful have been designs that have a metaphyseal sleeve with a tapered stem. A more recent newer concept has been the double taper neck designs which have not performed well in general. Anatomic Stem Designs: The rationale for an anatomic stem design was to design a component that matched the sagittal plane bow of the femur. The APR (Centerpulse, Austin, Texas) and the PCA (Howmedica, Rutherford, New Jersey) were the initial designs. Although these designs provided excellent micromotion stability, they are not used in their present length today because they could not fit in to all femurs. Straight Stem Designs: The concept of a straight stem design was to machine the femur to accept the prosthesis. This was done with diaphyseal reaming, proximal broaching, and preparing a proximal triangle to accommodate the proximal metaphyseal portion of the stem. These had previously, and still do, come in proximally coated and distally coated designs. They have proven to be durable long term. The AML fully coated stem (DePuy, Warsaw, Indiana) was and still is the prototype device. Tapered Stem Designs: The most popular designs today are the tapered stems. They are inserted either by a broach only, or ream and broach technique. Some only taper in the ML plane and are flat in the AP plane. These are called ML taper or blade devices (Taperloc and Trilock). These are usually inserted broach only. Some have a double taper with proximal fill and include the Zweymuller stem (Zimmer, Warsaw, Indiana), the Omnifit stem (Stryker, Mahwah, New Jersey), the Summit stem, and the Corail stem (both DePuy, Warsaw, Indiana). Some are hydroxyapatite coated (Omnifit and Corail), some are porous coated (Summit), and some are only grit blasted (Zweymuller). Some are broach only including the Zweymuller and Corail, and some are broach and ream including the Omnifit and Summit. Some are tapered throughout, one of which is a Wagner type design, Trilogy (Zimmer, Warsaw, Indiana). These Wagner type devices are useful in abnormal anatomy (CDH and Perthes). Modular Stem and Dual Modular Neck Designs: Metaphyseal sleeve modular stem designs are extremely versatile and can be inserted press fit into just about any femoral anatomy. They are most commonly utilised in cases of hip dysplasia with marked femoral anteversion. The S-ROM device is the prototype design. The long term concern with these as well as the double neck tapered devices is fretting and corrosion at the extra modular junctions. Short Stem Designs: Short stem designs were developed to provide metaphyseal only fixation and to enable easy insertion through small incision techniques, especially those performed through anterior and antero-lateral approaches.
The structure of two-parabolic space: parabolic dust and iteration

A non-elementary Mobius group generated by two-parabolics is determined up to conjugation by one complex parameter and the parameter space, the parameter space for representations of groups generated by two parabolics into \({PSL(2, \mathbb{C})}\) modulo conjugacy, has been extensively studied. In this paper, we use the results of Gilman and Waterman to obtain an additional structure for the parameter space, which we term the two-parabolic space. This structure allows us to identify groups that contain additional conjugacy classes of primitive parabolics, which we call parabolic dust groups, non-free groups off the real axis, and groups that are both parabolic dust and non-free; some of these contain \({\mathbb{Z} \times \mathbb{Z}}\) subgroups. The structure theorem also attaches additional geometric structure to discrete and non-discrete groups lying in given regions of the parameter space and allows a new explicit geometric construction of some non-classical T-Schottky groups.
Modeling of internal mechanical failure of all-solid-state batteries during electrochemical cycling, and implications for battery design

This is the first quantitative analysis of mechanical reliability of all-solid state batteries. Mechanical degradation of the solid electrolyte (SE) is caused by intercalation-induced expansion of the electrode particles, within the constrains of a dense microstructure. A coupled electro-chemo-mechanical model was implemented to quantify the material properties that cause an SE to fracture. The treatment of microstructural details is essential to the understanding of stress-localization phenomena and fracture. A cohesive zone model is employed to simulate the evolution of damage. In the numerical tests, fracture is prevented when electrode-particle's expansion is lower than 7.5% (typical for most Li-intercalating compounds) and the solid-electrolyte's fracture energy higher than Gc = 4 J m−2. Perhaps counter-intuitively, the analyses show that compliant solid electrolytes (with Young's modulus in the order of ESE = 15 GPa) are more prone to micro-cracking. This result, captured by our non-linear kinematics model, contradicts the speculation that sulfide SEs are more suitable for the design of bulk-type batteries than oxide SEs. Mechanical degradation is linked to the battery power-density. Fracture in solid Li-ion conductors represents a barrier for Li transport, and accelerates the decay of rate performance.
Optimizing the coherence of composite networks

We consider how to connect a set of disjoint networks to optimize the performance of the resulting composite network. We quantify this performance by the coherence of the composite network, which is defined by an H 2 norm of the system. Two dynamics are considered: noisy consensus dynamics with and without stubborn agents. For noisy consensus dynamics without stubborn agents, we derive analytical expressions for the coherence of composite networks in terms of the coherence of the individual networks and the structure of their interconnections. We also identify optimal interconnection topologies and give bounds on coherence for general composite graphs. For noisy consensus dynamics with stubborn agents, we show that the coherence of a composite network is a submodular function over the set of potential edges between the disjoint networks. We leverage this submodularity to develop a non-combinatorial algorithm that identifies connecting edges such that the composite network coherence is within a provable bound of optimal.
Quasiopen Sets, Bounded Variation and Lower Semicontinuity in Metric Spaces

In the setting of a complete metric space that is equipped with a doubling measure and supports a Poincare inequality, we show that the total variation of functions of bounded variation is lower semicontinuous with respect to L1-convergence in every 1-quasiopen set. To achieve this, we first prove a new characterization of the total variation in 1-quasiopen sets. Then we utilize the lower semicontinuity to show that the variation measures of a sequence of functions of bounded variation converging in the strict sense are uniformly absolutely continuous with respect to the 1-capacity.
MEASUREMENTS OF THE H(N,N) ANGULAR DISTRIBUTION OF 10MEV NEUTRON ENERGY

Relative measurements of the cross section for scattering of neutrons by protons have been made at 10 MeV neutron energy for center-of-mass neutron scattering angles from 60° to 180°. The measurements were made using the Ohio University Accelerator Laboratory’s tandem Van de Graaff accelerator with the D(d,n) reaction as the neutron source. The data are in good agreement with predictions from the phase shift analyses of Arndt, the groups of Nijmegen and Bonn, and the ENDF/B-V evaluation. The ENDF/B-Vl evaluation does not appear to have the same angular dependence as the data.
ADOPTION OF ROBOTIC VERSUS FLUOROSCOPIC GUIDANCE IN TOTAL HIP ARTHROPLASTY: IS ACETABULAR POSITIONING IMPROVED IN THE LEARNING CURVE?

Background Acetabulum positioning affects dislocation rates, component impingement, bearing surface wear rates, and need for revision surgery. Novel techniques purport to improve the accuracy and precision of acetabular component position, but may come have significant learning curves. Our aim was to assess whether adopting robotic or fluoroscopic techniques improve acetabulum positioning compared to manual THA during the learning curve. Methods Three types of THAs were compared in this retrospective cohort: 1) the first 100 fluoroscopically guided direct anterior THAs (fluoroscopic anterior, FA) done by a posterior surgeon learning the anterior approach, 2) the first 100 robotic assisted posterior THAs done by a surgeon learning robotic assisted surgery (robotic posterior, RP) and 3) the last 100 manual posterior THAs done by each surgeon (total 200 THAs) prior to adoption of novel techniques (manual posterior, MP). Component position was measured on plain radiographs. Radiographic measurements were done by two blinded observers. The percentage of hips within the surgeons' target zone (inclination 30°–50°, anteversion 10°–30°) was calculated, along with the percentage within the safe zone of Lewinnek (inclination 30°–50°; anteversion 5°–25°) and Callanan (inclination 30°–45°; anteversion 5°–25°). Relative risk and absolute risk reduction were calculated. Variances (square of the SDs) were used to describe the variability of cup position. Results 76% of MP THAs were within the surgeons' target zone compared with 84% of FA THAs and 97% of RP THAs. This difference was statistically significant, associated with a relative risk reduction of 87% (RR 0.13 [0.04–0.40], p<.01, ARR 21%, NNT 5) for RP compared to MP THAs. Compared to FA THAs, RP THAs were associated with a relative risk reduction of 81% (RR 0.19 [0.06–0.62], p<.01, ARR 13%, NNT 8). Variances were lower for acetabulum inclination and anteversion in RP THAs (14.0 and 19.5) as compared to the MP (37.5 and 56.3) and FA (24.5 and 54.6) groups. These differences were statistically significant (P<.01). Conclusion Adoption of robotic techniques delivers significant and immediate improvement in the precision of acetabular component positioning during the learning curve. While fluoroscopy has been shown to be beneficial with experience, a learning curve exists before precision improves significantly.
Følner tilings for actions of amenable groups

We show that every probability-measure-preserving action of a countable amenable group G can be tiled, modulo a null set, using finitely many finite subsets of G (“shapes”) with prescribed approximate invariance so that the collection of tiling centers for each shape is Borel. This is a dynamical version of the Downarowicz–Huczek–Zhang tiling theorem for countable amenable groups and strengthens the Ornstein–Weiss Rokhlin lemma. As an application we prove that, for every countably infinite amenable group G, the crossed product of a generic free minimal action of G on the Cantor set is $${\mathcal Z}$$ -stable.
Replacement-Lock and Dam No. 26: Lock Capacity Procedure and Scope

A systematic procedure integrating all relevant factors leading to a lock’s capacity should be used in determining the practical capacity of any lock on a navigable waterway. These factors should include representative commodity projections, average of maximum tons per lockage, average lockage time, seasonal considerations, and constraints on lock utilization (percent of time lock is in use). By expressing each of these factors on a monthly (i.e., seasonal) basis and then adjusting them over time to account for changes in commodity mix, tow configurations, and technology, it is possible to determine the probable monthly utilization of a lock. Based on queuing models, it was determined that at approximately 90% monthly utilization the practical capacity of a lock is realized. By introducing empirical lock data, many judgmental factors associated with seasonality are eliminated. The process used also shows that lock capacity is not a static condition. Since various factors are constantly in flux, the tonnage capacity varies every month and every year. Because the dynamic nature of the system requires numerous calculations, a computer program written in FORTRAN II was utilized.
Large Scale System Issues in Automated Highway and Air Traffic Management Systems

Abstract Large scale systems typically consist of compositions of many interacting sub-systems performing various planning and control functions. Control for such systems is often arranged in a hierarchical structure, with high level scheduling functions concerned with optimality and efficiency issues and low level control functions implementing the desired high level objectives and dealing with system uncertainty and safety. This paradigm leads to interactions between the fields of optimization and control theory. In this paper, these issues are highlighted using two large scale applications: Automated Highway Systems (AHS) and Air Traffic Management (ATM) Systems.
SEVERE SLIPPED CAPITAL FEMORAL EPIPHYSIS: ARTHROSCOPIC OSTEOPLASTY VERSUS OPEN NECK OSTEOTOMY: A RETROSPECTIVE ANALYSIS OF RESULTS

Purpose This report compares midterm results of open neck osteoplasty + neck osteotomy vs arthroscopic osteoplasty for severe Slipped Capital Femoral Epiphysis (SCFE). Method Database from 2006 to 2013 identified 22 patients out of 187 operations for SCFE. 12 underwent Open Neck Osteotomy (ONO) and osteoplasty by Ganz surgical dislocation approach. 10 underwent Arthroscopic Osteoplasty (AO). The mean follow-up for the ONO and AO groups were 59 (46 – 70), 36.1 (33 – 46) months respectively. Results The unpaired t -test showed that the post-operative corrections were significantly better in the ONO than the AO group. Slip angle (16.7° (1°–28.6°) Vs 47.1° (40.2° – 53.5°) p = .0003), head neck offset correction (5mm (2–13mm) Vs 0mm (0mm – 2mm) p = 0.0003), alpha angle (34.6° (23.2°–45.6°) Vs 61.88° (52.1° – 123°) p =0.0003), Modified Harris Hip Score (MHHS) (90(86.2–99) Vs 75.5 (58.75 – 96.8) p =0.003) and internal rotation p=0.0002 Paired t -test showed significant improvement in corrections within the individual groups compared with their own preoperative values. The results of AO group were oblique plane slip angle (55° (47.7° – 63.2°) Vs 47.1° (40.2° – 53.5°) p =0.001), alpha angle (90.7° (65° – 131°) Vs 61.88° (52.1° – 123°) p = 0.0001), head neck offset (0mm (−3 mm to 0mm) Vs 0mm (0mm – 2mm) p =0.001) and MHHS (52.7 (28.7 – 89.1) Vs 75.5 (58.75 – 96.8) p =0.0005). Complications in ONO group were varus malunion (1) and non-union(1) of the osteotomy. In the arthroscopic group persistent impingement in 3 patients and 5 were not able to return to sports. Conclusion Our results showed improved hip function following arthroscopic osteoplasty in severe SCFE. Considering the risks of an open surgical dislocation we could find that arthroscopy contributed worthy improvement in hip function in low demand patients.
Physiology of sporeforming bacteria associated with insects: minimal nutritional requirements for growth, sporulation, and parasporal crystal formation of Bacillus thuringiensis

A defined medium is described in which 18 strains of Bacillus thuringiensis representing the 12 established serotypes grow, sporulate, and produce a parasporal crystal. This minimal medium contains glucose and salts supplemented with either aspartate, glutamate, or citrate. These organic acids are required and cannot be replaced by vitamin mixtures or succinate even though succinate is taken up at a rate similar to that of aspartate, glutamate, and citrate.
Correction of Experimentally Produced Vesicoureteric Reflux in the Piglet by Intravesical Injection of Teflon

Vesicoureteric reflux was produced in eight piglets by opening their bladders and slitting the anterior intravesical wall of the ureter. Cystography confirmed the presence of bilateral reflux in six piglets and unilateral reflux in two. Six to eight weeks later the bladder was again opened and Teflon paste injected in the space behind the intravesical ureter, thereby creating a support for the submucosal ureter. Cystography four to six weeks after injection of Teflon paste showed absence of reflux in all animals. Intravenous pyelography showed obstruction at the vesicoureteric junction in only one of the 14 treated ureters and this was later confirmed at necropsy. Animals were followed up from one to six months and then were killed. Gross examination of the vesicoureteric region showed a well circumscribed subureteric Teflon mass of firm consistency, retaining its shape and position at the site of the injection. Histological examination showed encapsulation of the implant by a thin layer of fibrous tissue and a foreign body granulomatous reaction with histiocytes and giant cells within the implant. Hence it is technically feasible to correct experimentally produced vesicoureteric reflux in the piglet by intravesical injection of Teflon paste--a relatively inert material. It may now be possible to treat vesicoureteric reflux in man by endoscopic injection of Teflon behind the intravesical ureter.
Presidential Address of the 24th Annual Meeting of the American Society of Therapeutic Radiologists: Carcinoma of the Prostate, a Vexing Biological and Clinical Enigma

Adenocarcinoma of the prostate is a relatively common tumor in man; in 1982 it was estimated that in the United States 73,000 new cases were clinically diagnosed and 23,000 patients died of the disease.’ Biological characteristics Carcinoma of the prostate is a fascinatingly complex biological and clinical entity; this tumor has some similarities at the same time that a variety of features sets it aside from most other neoplasms in humans: Its etiology is unknown, its incidence increases with age and many times is incidentally found at autopsy or as has been reported in 3-4% of the prostatectomy specimens done for benign prostatic hypertrophy. The tumor usually originates in the peripheral acinar glands, although occasionally it may arise in the central ducts of the gland. Initially it may be localized but frequently is multifocal, involving all lobes of the prostate in over 60% of the cases.12 Although many tumors have a slow growth, there is a great deal of tumor cell heterogeneity and some of the lesions exhibit aggressive behavior with rapid demise of the patient.6s Carcinoma of the prostate is responsive to irradiation depending on the size of the lesion; about 75% of the tumors exhibit transient response to hormones but sensitivity to cytotoxic agents so far remains elusive. Recently, tissue and tumor specific and associated antigens have been identified in several animal tumor systems.‘3*6’ The prostatic cell is the target for a large number of hormonal and chemical substances that control the gland’s proliferative rate and biological behavior; this influence stems from organs as close as the testicle or the adrenal cortex or as far away as the pituitary and the hypothalmus.56 The effects of these hormones are mediated through a variety of cytoplasmic and nuclear hormonal receptors
Percutaneous Transluminal Renal Angioplasty. The Evolution of a Procedure

Renovascular hypertension, the type seen in approximately 4% of the hypertensive population in this country,1poses the double threat of severe hypertension (with its complications) and progressive renal insufficiency. Pharmacotherapy, surgical revascularization, or both, the traditional modes of treatment, have significant shortcomings. Drugs often only partially control blood pressure (BP); when several are used, side effects and poor patient compliance can become a problem.2-4Surgery requires general anesthesia, and many patients are poor risks because of severe diffuse atherosclerotic disease or renal insufficiency. Moreover, the results of surgery vary; there is considerable morbidity, and the mortality is 5.9%.5Despite these shortcomings, therapy can have significant benefits.6,7 A third therapeutic modality, percutaneous transluminal angioplasty (PTA), is presently undergoing evaluation. Percutaneous transluminal angioplasty is not a new procedure. It was originally developed by Dotter and Judkins8for the treatment of atherosclerotic peripheral vascular disease. The procedure was
Embolization Techniques in the Urinary Tract

Transcatheter embolization of genitourinary pathology has enjoyed widespread acceptance over the past several years. In many centers, preoperative embolization of hypervascular renal-cell carcinomas has become a routine practice and, in patients deemed unresectable, may be used as a primary form of therapy. The authors present the indications for embolization and discuss relevant technical points.
The Role of Bacterial Virulence Factors and Tamm-Horsfall Protein in the Pathogenesis of Escherichia Coli Urinary Tract Infection in Infants

• Forty-three patients and 70 controls were enrolled in an open study to evaluate the role of bacterial virulence factors and Tamm-Horsfall protein (THP) in the pathogenesis of urinary tract infection (UTI) due to Escherichia coli . The ages of the patients and controls ranged from 5 days to 6 months. Nine patients had upper UTIs and 33 patients had lower UTIs, based on bacteremia and radiographic evidence. There were no differences between patients and controls in the percentages of strains showing hemolytic activity of E coli strains isolated from periurethral and rectal cultures. Urinary E coli strains recovered from patients showed a significantly higher percentage of mannose-resistant hemagglutination, greater P and X fimbriation, more type 1 pill, and the presence of mannose-sensitive and mannose-resistant hemagglutination when compared with E coli strains recovered from the controls. The O but not the K pyelonephritogenic serotypes were more commonly recovered from patients than from controls. The mean THP concentrations in urine (micrograms of THP per milligrams of creatinine) were 29.9 and 91.4 μg/mg for patients and controls, respectively. With the exception of hemagglutination properties and certain pyelonephritogenic O serotypes, other virulence factors of E coli could not be defined in our Infant population. The role of THP, if any, in the pathogenesis of UTI remains unresolved. ( AJDC 1987;141:1230-1234)
Stability study of native epitaxial transistors as process probe for contamination detection

Methods for detecting contamination with native transistor probes are reviewed. This review is based on experience which was accumulated during development of multilevel epitaxial (EPI) high voltage DMOS process technologies including Deep Trench Isolation (DTI) with isolation capabilities up to and above 100V. Potential contamination sources, mechanisms and characterization are critically discussed. Authors identified five sources of dopant contamination: device EPI architecture, backside seal film budget, pre/post EPI cleans, cross tool contamination and high energy implants. Native NMOSFET device was used for detecting the low dopant contamination levels. Analyzing unique wafer patterns for native transistor threshold voltage can help point to a solution path.
Family Communication at the End of Life.

People often feel awkward and ill at ease when faced with the opportunity for communication at the end of life, thus the overall theme for the articles in this special issue is the creation of more awareness and knowledge regarding the depth, breadth, and importance of current research exploring family communication at the end of life. This introductory essay attempts to accomplish the following: (1) discuss the importance of talk regarding death; (2) highlight the formative role of family interactions on the death and dying process; and (3) outline the articles in this special issue. Scholars contributing to this special issue on “Family Communication at the End of Life” have provided evidence that communication is important between and for terminally ill individuals, family members, and healthcare/palliative care specialists. Overall, research exploring communication at the end of life is especially relevant because every person experiences the death and loss of loved ones, and ultimately faces the reality of their own death.
Electroencephalographic markers of brain development during sevoflurane anaesthesia in children up to 3 years old.

Abstract Background General anaesthetics generate spatially defined brain oscillations in the EEG that relate fundamentally to neural-circuit architecture. Few studies detailing the neural-circuit activity of general anaesthesia in children have been described. The study aim was to identify age-related changes in EEG characteristics that mirror different stages of early human brain development during sevoflurane anaesthesia. Methods Multichannel EEG recordings were performed in 91 children aged 0–3 yr undergoing elective surgery. We mapped spatial power and coherence over the frontal, parietal, temporal, and occipital cortices during maintenance anaesthesia. Results During sevoflurane exposure: (i) slow–delta (0.1–4 Hz) oscillations were present in all ages, (ii) theta (4–8 Hz) and alpha (8–12 Hz) oscillations emerge by ∼4 months, (iii) alpha oscillations increased in power from 4 to 10 months, (iv) frontal alpha-oscillation predominance emerged at ∼6 months, (v) frontal slow oscillations were coherent from birth until 6 months, and (vi) frontal alpha oscillations became coherent ∼10 months and persisted in older ages. Conclusions Key developmental milestones in the maturation of the thalamo-cortical circuitry likely generate changes in EEG patterns in infants undergoing sevoflurane general anaesthesia. Characterisation of anaesthesia-induced EEG oscillations in children demonstrates the importance of developing age-dependent strategies to monitor properly the brain states of children receiving general anaesthesia. These data have the potential to guide future studies investigating neurodevelopmental pathologies involving altered excitatory–inhibitory balance, such as epilepsy or Rett syndrome.
The HAND1 frameshift A126FS mutation does not cause hypoplastic left heart syndrome in mice.

Aims To test if a human Hand1 frame shift mutation identified in human samples is causative of hypoplastic left heart syndrome (HLHS). Methods and results HLHS is a poorly understood single ventricle congenital heart defect that affects two to three infants in every 10 000 live births. The aetiologies of HLHS are largely unknown. The basic helix-loop-helix transcription factor HAND1 is required for normal heart development. Interrogation of HAND1 sequence from fixed HLHS tissues identified a somatic frame-shift mutation at Alanine 126 (NP_004812.1 p.Ala126Profs13X defined as Hand1A126fs). Hand1A126fs creates a truncated HAND1 protein that predictively functions as dominant negative. To determine if this mutation is causative of HLHS, we engineered a conditional Hand1A126fs mouse allele. Activation of this allele with Nkx2.5Cre results in E14.5 lethality accompanied by cardiac outflow tract and intraventricular septum abnormalities. Using αMHC-Cre or Mef2CAHF-Cre to activate Hand1A126fs results in reduced phenotype and limited viability. Left ventricles of Hand1A126FS mutant mice are not hypoplastic. Conclusions Somatically acquired Hand1A126FS mutation is not causative of HLHS. Hand1A126FS mutation does exhibit embryonic lethal cardiac defects that reflect a dominant negative function supporting the critical role of Hand1 in cardiogenesis.
A Survey of Morcellator Preference and Cost Comparison of the Lumenis VersaCut and Wolf Piranha Morcellators.

Objective To evaluate operating room (OR) costs associated with the 2 available morcellators in the United States in a matched cohort and to determine benign prostatic hyperplasia surgeon's morcellator preference. Materials and Methods Patients from 2013, the last year our institution exclusively used the VersaCut device, were matched 1:1 with the most recent patient cohort, utilizing the Wolf Piranha morcellator. Cost of morcellation including the expense of OR time and disposable instrument costs were calculated. A survey to the Endourological Society e-mail listserv was sent to determine morcellator preference. Results We identified 142 patients who underwent holmium laser enucleation of the prostate in 2013. When compared with the VersaCut group, morcellation efficiency (4.4 vs 7.0 g/min, P A total of 126 urologists responded to the survey. Of these, 56 (44.5%) perform transurethral prostate enucleations, which included 48 (86%) holmium. More endourologists use the VersaCut (n = 33, 59%) than the Piranha (n = 24, 43%) morcellator. Qualities that impacted the preference of morcellator included the preferred device is safer, faster, easier to use, reusable, and less expensive. Conclusion We identified a significant improved efficiency and improved cost savings utilizing the Piranha morcellator even when controlling for disposable costs. Of the endourologists who responded to the survey, less than half perform transurethral enucleation. Morcellator preference is largely based on safety, efficiency, and ease of use, whereas cost and reusablility were of lesser importance.
An optimal algorithm for shortest paths on weighted interval and circular-arc graphs, with applications

We give the first linear-time algorithm for computing single-source shortest paths in a weighted interval or circular-arc graph, when we are given the model of that graph, i.e., the actual weighted intervals or circular-arcsand the sorted list of the interval endpoints. Our algorithm solves this problem optimally inO(n) time, wheren is the number of intervals or circular-arcs in a graph. An immediate consequence of our result is anO(qn + n logn)-time algorithm for the minimum-weight circle-cover problem, whereq is the minimum number of arcs crossing any point on the circle; then logn term in this time complexity is from a preprocessing sorting step when the sorted list of endpoints is not given as part of the input. The previously best time bounds were0(n logn) for this shortest paths problem, andO(qn logn) for the minimum-weight circle-cover problem. Thus we improve the bounds of both problems. More importantly, the techniques we give hold the promise of achieving similar (logn)-factor improvements in other problems on such graphs.
Embedding obstructions and 4-dimensional thickenings of 2-complexes

The vanishing of Van Kampen’s obstruction is known to be necessary and sufficient for embeddability of a simplicial n-complex into R2n for n 6= 2, and it was recently shown to be incomplete for n = 2. We use algebraictopological invariants of four-manifolds with boundary to introduce a sequence of higher embedding obstructions for a class of 2-complexes in R4.
An Energy-Efficient and Distributed Cooperation Mechanism for $k$ -Coverage Hole Detection and Healing in WSNs

Present approaches to achieve $k$ -coverage for Wireless Sensor Networks still rely on centralized techniques. In this paper, we devise a distributed method for this problem, namely Distributed VOronoi based Cooperation scheme (DVOC), where nodes cooperate in hole detection and recovery. In previous Voronoi based schemes, each node only monitors its own critical points. Such methods are inefficient for $k$ -coverage because the critical points are far away from their generating nodes in $k$ -order Voronoi diagram, causing high cost for transmission and computing. As a solution, DVOC enables nodes to monitor others’ critical points around themselves by building local Voronoi diagrams (LVDs). Further, DVOC constrains the movement of every node to avoid generating new holes. If a node cannot reach its destination due to the constraint, its hole healing responsibility will fall to other cooperating nodes. The experimental results from the real world testbed demonstrate that DVOC outperforms the previous schemes.
Sports Sentiment and Tipping Behavior

Abstract This paper utilizes a high frequency dataset on taxi rides in New York City to investigate how emotions due to sporting event outcomes affect passengers’ tipping behavior. I formulate and empirically test a reference-dependent preferences framework of tipping behavior. The results indicate that the tipping amounts are driven by deviations from expectations much more so than wins and losses, with the most salient effects found under unexpected close wins. However, there is no support for loss aversion. The findings suggest that loss averse behavior may be subdued in the presence of social norms while surprises can result in freedom on the upside of tipping.
Nanoparticle–Cell Interactions: Relevance for Public Health

Nanoparticles, especially metal oxide nanoparticles, are used in a wide range of commercial and industrial applications that result in direct human contact, such as titanium dioxide nanoparticles in paints, food colorings, and cosmetics, or indirectly through release of nanoparticle-containing materials into the environment. Workers who process nanoparticles for downstream applications are exposed to especially high concentrations of nanoparticles. For physical chemists, nanoparticles present an interesting area of study as the small size of nanoparticles changes the properties from that of the bulk material, leading to novel properties and reactivity. For the public health community, this reduction in particle size means that exposure limits and outcomes that were determined from bulk material properties are not necessarily valid. Informed determination of exposure limits requires a fundamental understanding of how nanoparticles interact with cells. This Feature Article highlights the areas of intersecti...
The ‘China shock,’ exports and U.S. employment: A global input–output analysis

This paper quantifies the impact on U.S. employment from imports and exports during 1995–2011, using the World Input–Output Database. We find that the growth in U.S. exports led to increased demand for 2 million jobs in manufacturing, 0.5 million in resource industries, and a remarkable 4.1 million jobs in services, totaling 6.6 million. Two‐thirds of those service sectors jobs are due to the export of services themselves, whereas one‐third is due to the intermediate demand from manufacturing and resource—or merchandise—exports, so the total labor demand gain due to merchandise exports was 3.7 million jobs. In comparison, U.S. merchandise imports from China led to reduced demand of 1.4 million jobs in manufacturing and 0.6 million in services (with small losses in resource industries), with total job losses of 2.0 million. It follows that the expansion in U.S. merchandise exports relative to imports from China over 1995–2011 created net demand for about 1.7 million jobs. Comparing the growth of U.S. merchandise exports to merchandise imports from all countries, we find a fall in net labor demand due to trade, but comparing the growth of total U.S. exports to total imports from all countries, then there is a rise in net labor demand because of the growth in service exports.
Assessing the capacity of social determinants of health data to augment predictive models identifying patients in need of wraparound social services.

Introduction A growing variety of diverse data sources is emerging to better inform health care delivery and health outcomes. We sought to evaluate the capacity for clinical, socioeconomic, and public health data sources to predict the need for various social service referrals among patients at a safety-net hospital. Materials and methods We integrated patient clinical data and community-level data representing patients' social determinants of health (SDH) obtained from multiple sources to build random forest decision models to predict the need for any, mental health, dietitian, social work, or other SDH service referrals. To assess the impact of SDH on improving performance, we built separate decision models using clinical and SDH determinants and clinical data only. Results Decision models predicting the need for any, mental health, and dietitian referrals yielded sensitivity, specificity, and accuracy measures ranging between 60% and 75%. Specificity and accuracy scores for social work and other SDH services ranged between 67% and 77%, while sensitivity scores were between 50% and 63%. Area under the receiver operating characteristic curve values for the decision models ranged between 70% and 78%. Models for predicting the need for any services reported positive predictive values between 65% and 73%. Positive predictive values for predicting individual outcomes were below 40%. Discussion The need for various social service referrals can be predicted with considerable accuracy using a wide range of readily available clinical and community data that measure socioeconomic and public health conditions. While the use of SDH did not result in significant performance improvements, our approach represents a novel and important application of risk predictive modeling.
Rotamers of Isoprene: Infrared Spectroscopy in Helium Droplets and Ab Initio Thermochemistry.

Isoprene (C5H8) is an abundant, reactive tropospheric hydrocarbon, derived from biogenic emissions. A detailed understanding of the spectroscopy of isoprene is therefore desirable. Isoprene monomer is isolated in helium droplets and its infrared spectrum is measured in the CH stretching region. Anharmonic frequencies are predicted by VPT2+K simulations employing CCSD(T) force fields with quadratic (cubic and quartic) force constants computed using the ANO1 (ANO0) basis set. The vast majority of the spectral features can be assigned to trans-isoprene on the basis of these computations. Some features of the higher energy gauche conformer are also assignable, by comparison to experiments using heated isoprene. Convergent ab initio thermochemistry is presented for the isomerization pathway, for which the partition function explicitly accounts for the eigenstates associated with separate, uncoupled one-dimensional potential surfaces for methyl torsion and internal rotation between rotamers. The respective 0 an...
Did UberX reduce ambulance volume

Ambulances are a vital part of emergency medical services. However, they come in single, high intervention form, which is at times unnecessary, resulting in excessive costs for patients and insurers. In this paper, we ask whether UberX's entry into a city caused substitution away from traditional ambulances for low-risk patients, reducing overall volume. Using a city-panel over-time and leverage that UberX enter markets sporadically over multiple years, we find that UberX entry reduced the per capita ambulance volume by at least 6.7%. Our result is robust to numerous specifications.
Corrective model-predictive control in large electric power systems

Enhanced control capabilities are required to coordinate the response of increasingly diverse controllable resources, including FACTS devices, energy storage, demand response and fast-acting generation. Model-predictive control (MPC) has shown great promise for accommodating these devices in a corrective control framework that exploits the thermal overload capability of transmission lines and limits detrimental effects of contingencies. This work expands upon earlier implementations by incorporating voltage magnitudes and reactive power into the system model utilized by MPC. These improvements provide a more accurate prediction of system behavior and enable more effective control decisions. Performance of this enhanced MPC strategy is demonstrated using a model of the Californian power system containing 4259 buses. Sparsity in modelling and control actions must be exploited for implementation on large networks. A method is developed for identifying the set of controls that is most effective for a given contingency. The proposed MPC corrective control algorithm fits naturally within energy management systems where it can provide feedback control or act as a guide for system operators by identifying beneficial control actions across a wide range of devices.
Cybersecurity in Hospitals: A Systematic, Organizational Perspective

Background: Cybersecurity incidents are a growing threat to the health care industry in general and hospitals in particular. The health care industry has lagged behind other industries in protecting its main stakeholder (ie, patients), and now hospitals must invest considerable capital and effort in protecting their systems. However, this is easier said than done because hospitals are extraordinarily technology-saturated, complex organizations with high end point complexity, internal politics, and regulatory pressures. Objective: The purpose of this study was to develop a systematic and organizational perspective for studying (1) the dynamics of cybersecurity capability development at hospitals and (2) how these internal organizational dynamics interact to form a system of hospital cybersecurity in the United States. Methods: We conducted interviews with hospital chief information officers, chief information security officers, and health care cybersecurity experts; analyzed the interview data; and developed a system dynamics model that unravels the mechanisms by which hospitals build cybersecurity capabilities. We then use simulation analysis to examine how changes to variables within the model affect the likelihood of cyberattacks across both individual hospitals and a system of hospitals. Results: We discuss several key mechanisms that hospitals use to reduce the likelihood of cybercriminal activity. The variable that most influences the risk of cyberattack in a hospital is end point complexity, followed by internal stakeholder alignment. Although resource availability is important in fueling efforts to close cybersecurity capability gaps, low levels of resources could be compensated for by setting a high target level of cybersecurity. Conclusions: To enhance cybersecurity capabilities at hospitals, the main focus of chief information officers and chief information security officers should be on reducing end point complexity and improving internal stakeholder alignment. These strategies can solve cybersecurity problems more effectively than blindly pursuing more resources. On a macro level, the cyber vulnerability of a country’s hospital infrastructure is affected by the vulnerabilities of all individual hospitals. In this large system, reducing variation in resource availability makes the whole system less vulnerable—a few hospitals with low resources for cybersecurity threaten the entire infrastructure of health care. In other words, hospitals need to move forward together to make the industry less attractive to cybercriminals. Moreover, although compliance is essential, it does not equal security. Hospitals should set their target level of cybersecurity beyond the requirements of current regulations and policies. As of today, policies mostly address data privacy, not data security. Thus, policy makers need to introduce policies that not only raise the target level of cybersecurity capabilities but also reduce the variability in resource availability across the entire health care system.
Anticipated Consumption and its Impact on Capital Accumulation and Growth: 'Forward-Looking' vs. 'Backward-Looking' Consumption Reference

It has long been argued that the anticipations of some future event will impact current consumption and well-being in advance of the occurrence of the event itself. This paper introduces this idea of anticipated pleasure into the Ramsey growth model, by assuming that in addition to his own current consumption, an agent’s current utility depends upon a reference consumption level that is based on expected future consumption. Two alternative specifications of the anticipated future consumption levels are considered: an external index and an internal index. We analyze the macrodynamic equilibrium, comparing it to both the standard Ramsey model, and the more familiar parallel model of habit formation. We establish a number of theoretical propositions characterizing the impact of the anticipated consumption reference on the transitional dynamics and long-run equilibrium, supplementing these with extensive numerical simulations. JEL-Code: D900, E200.
Automated analysis of long-term grooming behavior in Drosophila using a k-nearest neighbors classifier.

From birds that preen their feathers to dogs that lick their fur, many animals groom themselves. They do so to stay clean, but routine grooming also has a range of other uses, such as social communication or controlling body temperature. Despite its importance, grooming remains poorly understood; it is especially unclear how this behavior is regulated. Fruit flies could be a good model to study grooming because they are often used in laboratories to look into the genetic and brain mechanisms that control behavior. Flies clean themselves by sweeping their legs over their wings and body, but little is known about how the insects groom ‘naturally’ over long periods of time. This is partly because scientists have had to recognize and classify grooming behavior by eye, which is highly time-consuming. Here, Qiao, Li et al. have created a system to automatically detect grooming behavior in fruit flies over time. First, a camera records the movement of an individual insect. A computer then analyzes the images and picks out general features of the fly’s movement that can help work out what the insect is doing. For example, if a fly is moving its limbs, but not the main part of its body, it is probably grooming itself. Qiao, Li et al. then borrowed an algorithm from an area of computer science known as ‘machine learning’ to teach the computer how to classify each fly’s behavior automatically. The new system successfully recognized grooming behavior in over 90% of cases, and it revealed that fruit flies spend about 13% of their waking life grooming. It also showed that grooming seems to be controlled by two potentially independent internal programs. One program is tied to the internal body clock of the fly, and regulates when the insect grooms during the day. The other commands how long the fly cleans itself, and balances the amount of time spent on grooming with other behaviors. Cleaning oneself is not just important for animals to stay disease-free: it also reflects the general health state of an individual. For example, a loss of grooming is associated with sickness, old age, and, in humans, with mental illness. If scientists can understand how grooming is controlled at the brain and molecular levels, this may give an insight into how these mechanisms relate to diseases. The system created by Qiao, Li et al. could help to make such studies possible.
A Comparison of Cerebellar Retraction Pressures in Posterior Fossa Surgery: Extended Retrosigmoid Versus Traditional Retrosigmoid Approach.

Background The retrosigmoid approach is broadly applicable to many posterior fossa procedures. However, cerebellar retraction is often necessary for lesions in the cerebellopontine angle, which can lead to complications. An extended retrosigmoid approach skeletonizes the sigmoid sinus and allows a wider corridor with less retraction. This study investigated the differences in retraction pressure between the retrosigmoid and extended retrosigmoid approach in a cadaveric model. Methods Anatomic dissection of 2 cadaveric heads was performed for comparison of surgical approaches. Bilateral measurements were obtained on each head, providing 4 sets of data. Retrosigmoid craniotomy was first performed with recording of retraction pressure necessary for 1.5-cm exposure. The exposure was then expanded to an extended retrosigmoid approach, and retraction pressures were recorded. Results Mean retraction pressure in cadaver 1 for retrosigmoid and extended retrosigmoid approaches was 20.25 ± 5.9 mm Hg and 10.25 ± 3.8 mm Hg, respectively; in cadaver 2, values were 11.75 ± 3.1 mm Hg and 4.75 ± 1.8 mm Hg, respectively. This corresponded to a mean relative reduction in retraction pressure of 49.4% in cadaver 1 and 59.6% in cadaver 2 by using the extended retrosigmoid approach. Retraction pressures were also significantly less (P Conclusions The extended retrosigmoid approach gains better visualization with reduced brain retraction. In our study, cerebellar retraction pressures were greatly reduced when using the extended retrosigmoid approach in a cadaveric model.