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Authors are grateful to the Royal Astronomical Society for supporting Toby Peres summer studentship. RAS funding for a biographical database of scientists has thrown up a story of confusion and fake news surrounding the Paris Observatory's search for a new director in 1907. Toby Peres, Jose Gomez Mena, Edmund Robertson, Isobel Falconer and John O'Connor report. Postprint Non

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The fathers of matrix quantum mechanics believed that the quantum particles are unanschaulich (unvisualizable) and that quantum particles pop into existence only when we measure them. Challenging the orthodoxy, in 1926 Erwin Schrödinger developed his wave equation that describes the quantum particles as a packet of quantum probability amplitudes evolving in space and time. Thus, Schrödinger visualized the unvisualizable and lifted the veil that has been obscuring the wonders of the quantum world.Quanta 2017; 6: 48–52.

The ICFDA’ 14 will be organized and hosted by the University of Catania, DIIEI (Dipartimento di Ingegneria, Elettrica, Elettronica e Informatica) in Catania, Italy. This conference is technically co-sponsored by IEEE (Institute of Electrical and Electronics Engineers), the world’s largest technical professional association. The event is already announced on the IEEE calendar, search for “ICFDA” or for June 2014, at: http://www.ieee.org/conferences events/conferences/organizers/conference organizer quick links.html#. The ICFDA’ 14 is a continuation, the 7th in the series of the previous FDA meetings: 2004 in France, 2006 in Portugal, 2008 Turkey, 2010 in Spain, 2012 in China, 2013 in France, see Previous Events at http://www.icfda14.dieei.unict.it/previous.html. As such, its topics will include all traditional FDA topics on fractional order systems and models, both in theoretical and application aspects. Now their list is extended to yet wider range, due to the growing research and development on fractional calculus in the areas of mathematics, physics and engineering, both from university and industry, that motivates this international event to gather, unify and enlarge the FDA community.

The development of a mathematical model of the knee ligaments in the sagittal plane is presented. Essential features of the model are (a) the representation of selected cruciate ligament fibres as isometric links in a kinematic mechanism that controls passive knee flexion and (b) the mapping of all other ligament fibres between attachments on the tibia and femur. Fibres slacken and tighten as the ligament attachment areas on the bones move relative to each other. The model is used to study the shape and fibre length changes of the cruciate and collateral ligaments in response to passive flexion/extension of the knee. The model ligament shape and fibre length changes compare well qualitatively with experimental results reported in the literature. The results suggest that when designing and implanting a ligament replacement with the aim of reproducing the natural fibre strain patterns, the surgeon must not only implant through the natural attachment areas but must also maintain the natural fibre mapping and render all fibres just tight at the appropriate flexion angle.

A folder of manuscript and printed material has recently been brought to our attention by a descendant of William Wallace. Wallace was Professor of Mathematics at Edinburgh University from 1819 to 1838 and previously taught at the Royal Military College, Marlow and Sandhurst. Copies of much of this material have now been put on a website, with the owners' approval. Here we describe the contents, which include samples by David Gregory and John Landen, and letters to Wallace from William Herschel, Henry Brougham, Alexander Christison, ‘Mrs Greig’ (Mary Fairfax Somerville), Walter Scott, and others. Other material includes Wallace's letters of appointment, a printed pamphlet on the burial place of John Napier, a list of mathematical books in Wallace's library in 1792, correspondence on astronomy and surveying, and a Russian translation of Wallace's work on conics.

We give necessary and sufficient conditions for the efficiency of the direct product of finitely many finite monogenic monoids. © 2007 AMSS CAS & SUZHOU UNIV.

A general method is presented for enumerating the distinct self-similar sets that arise as attractors of certain families of iterated function systems, using group theory to analyse the symmetries of the attractors. A range of examples are investigated in this way. 2000 AMS subject classification: 28A80, 20B40

Finite element models of bone segments generated from computed tomography data using automatic mesh generation algorithms are becoming common not only in research but also in clinical applications such as computer aided orthopaedic surgery. Especially in the case of the latter application, the models cannot be verified against an experimental measurement, therefore their inherent accuracy should be well known before drawing conclusions based on the calculated results. This study was carried out to assess the performance of tetrahedral solid finite elements with linear and quadratic displacement functions when they are used to mesh the human femur in conjunction with automatic mesh generator methods. Ten-node quadratic tetrahedra (T10) having parabolic displacement functions were compared with four-node linear tetrahedron elements (T4) on the basis of accuracy and central processing unit (CPU) time. From the analyses of 11 finite element meshes, it was concluded that linear tetrahedral elements should be avoided and quadratic tetrahedral elements ought to be chosen for the purposes of finite element analysis of the human femur. When incremental loading and iterative solution is necessary, the coarsest possible T10 mesh compatible with accuracy is needed to minimize computer capacity and CPU time.

The orientations and moment arms of the knee extensor and flexor muscle tendons are evaluated with increasing values of muscle force during simulated isometric exercises. A four-bar linkage model of the knee in the sagittal plane was used to define the motion of the joint in the unloaded state during 0–120° flexion. The cruciate and collateral ligaments were represented by arrays of elastic fibres, which were recruited sequentially under load or remained buckled when slack. A bi-articular model of the patello-femoral joint was used. Simple straight-line representation was used for the lines of action of the forces transmitted by the model muscle tendons. The effects of tissue deformation with increasing muscle force were considered. During quadriceps contraction resisted by an external flexing load, the maximum change in moment arm of the patellar tendon was found to be 2 per cent at 0° flexion when the quadriceps force was increased tenfold, from 250 to 2500 N. The corresponding maximum change in orientation of the tendon was 3° at 120° flexion. During hamstrings contraction resisted by an external extending load, the maximum change in moment arm of the hamstrings tendon was 8 per cent at 60° flexion when the hamstrings force was increased tenfold, from 100 to 1000 N. During gastrocnemious contraction, the corresponding maximum change for the gastrocnemious tendon was 3 per cent at 0°. The orientations of the flexor muscle tendons in this range of force either remained constant or changed by 1° or less at any flexion angle. The general trend at any flexion angle was that, as the muscle force was increased, the moment arms and the orientations approached nearly constant values, showing asymptotic behaviour. It is concluded that experimental simulations of knee muscle action with low values of the externally applied load, of the order of 50 N, can provide reliable estimates of the relationships between muscle forces and external loads during activity.

is said to be efficient if it can be defined by a presentation (A | R) with |R| -|A|=rank(H 2(S)). In this paper we demonstrate certain infinite classes of both efficient and inefficient semigroups. Thus, finite abelian groups, dihedral groups D 2 n with n even, and finite rectangular bands are efficient semigroups. By way of contrast we show that finite zero semigroups and free semilattices are never efficient. These results are compared with some well-known results on the efficiency of groups.

A common clinical strategy for relief of pressure sores is theuse of pressure redistributing beds, mattresses and overlays. Alarge-scale mattress replacement was scheduled for 1998 andthis led to a multi-professional review of the pressure-relievingproperties of a range of foam mattresses. Mattresses weresubjected to 48 h indentor testing. Attention was paid to theabsolute peak pressures and the percentage change relative tothe initial readings. Having achieved a high ranking in indentortesting, selected mattresses were placed in the clinical settingfor a one-week period. A purchasing decision was made basedupon indentor testing, clinical evaluation and by examining price.For confirmation, a number of other major users were consulted.The 13 mattresses provided variable pressure relievingproperties. A process of exclusion was adopted in order to finda subset suitable for clinical evaluation. The standard NHSmattress performed poorly. One type was dual-function wherebythe mattress was intended to be matched for patient weight,having a "heavy" and a "light" side (deemed to be impractical).Some generated high initial pressures and were removed. Wediscarded mattresses that produced an increase in pressure overthe 24 h loading or that responded poorly after the rest period.The remaining mattresses were deemed suitable, on an equalbasis, for further testing. Three mattresses were placed on clinicaltrial for a one-week period, all performing satisfactorily. Pricewas examined in the context of manufacturers' guarantee usedas an indication of mattress life. On the basis of these findings,the team of nurses and engineers were able to make a purchasingrecommendation. We are confident that this will lead to fewerpressure sores, improved care and better patient outcome.

An elastostatic model of rapidly loaded articular cartilage is presented. It is assumed that the cartilage experiences little volumetric change or interstitial fluid flow while loaded instantaneously. Subchondral bone compliance and articular surface friction are incorporated. Integral representations of the stress distributions within cartilage are derived using Fourier transform techniques and the integrals are solved numerically. Localized tensile stresses are found and occur in regions close to the cartilage-bone interface as well as at the articular surface, outside the embrace of the load. The qualitative similarity between the results and those of previous investigations is explained by an elementary equilibrium analysis. The stress distributions suggest that the splits and cracks observed in diseased cartilage may be initiated, or propagated, by tensile stress.

Summary Many experimental protocols and published guidelines for performing bronchoscopy, bronchoalveolar lavage (BAL), bronchial biopsies, and segmental antigen challenge (SAC) of allergic asthmatic subjects recommend treating subjects with a β -agonist prior to the procedure. However, the effect of β -agonist pretreatment has not been reported. In a retrospective analysis of ragweed allergic subjects undergoing bronchoscopy, SAC, and BAL, we examined the effect of albuterol pretreatment on cellular influx and lung injury produced by antigen challenge. Forty-eight subjects, 17 who received no pretreatment and 31 who received four puffs of albuterol prior to bronchoscopy, comprised the study groups. No parameter monitored in BAL fluid 24 h after SAC (total cells, macrophages, neutrophils, eosinophiis, lymphocytes, total protein, albumin, or eosinophil cationic protein) differed in subjects pretreated with albuterol when compared with subjects who were not pretreated. Although additional, prospective studies are warranted, we conclude that β -agonist pretreatment of experimental subjects does not alter many aspects of the inflammatory response produced by SAC.

A mathematical model of the knee ligaments in the sagittal plane is used to study the forces in the cruciate and collateral ligaments produced by anterior/posterior tibial translation. The model is based on ligament fibre functional architecture. Geometric analysis of the deformed configurations of the model ligaments provides the additional compatibility conditions necessary for calculation of the statically indeterminate distributions of strain and stress within the ligaments and the sharing of load between ligaments. The investigation quantifies the process of ligament fibre recruitment, which occurs when fibres made slack by passive flexion/extension of the knee stretch and change their spatial positions in order to resist applied loads. The calculated ligament forces are in reasonable agreement with experimental results reported in the literature. The model explains some subtleties of ligament function not incorporated in models that represent the ligaments by a small number of lines.

Dopamine release is regulated by presynaptic dopamine receptors and interactions between adenosine and dopamine receptors have been well documented. In the present study, dopamine release from isolated striatal slices from Wistar rats was measured using fast cyclic voltammetry. Single-pulse stimulation (0.1 ms, 10 V) was applied every 5 min over a 2-h period. Superfusion with the adenosine (A)(1) receptor agonist N(6)-cyclopentyladenosine (CPA), but not the A(2) receptor agonist 3-[4-[2-[[6-amino-9-[(2R,3R,4S,5S)-5-(ethylcarbamoyl)-3,4-dihydroxy-oxolan-2-yl]purin-2-yl]amino]ethyl] phenyl]propanoic acid (CGS 21680), inhibited dopamine release in a concentration-dependent manner (IC(50) 3.80 x 10(-7) m; n = 10). The dose-response curve to CPA was shifted to the right (IC(50) 6.57 x 10(-6) m; n = 6, P0.05 vs. control) by the A(1) receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX). Neither the D(1) agonist 6-chloro-APB nor the D(1) antagonist R-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3- benzazepine-7-ol (SCH 23390) altered dopamine release on their own. However, SCH 23390 (3 microm) significantly attenuated the response to CPA (IC(50) 1.44 x 10(-5) m; n = 6, P0.01 vs. control). Furthermore, the inhibitory effect of CPA was significantly increased in the presence of 6-chloro-APB (1 microm). In radioligand binding experiments, CPA interacted with high- and low-affinity states of [(3)H]DPCPX-lableled A(1) receptors. The high-affinity agonist binding to A(1) receptors was inhibited by the stable guanosine triphosphate analogue Gpp(NH)p. In contrast, neither the proportion nor the affinity of high-affinity A(1) receptors was altered by dopamine or SCH 23390. These results provide evidence that the inhibition of dopamine release by adenosine A(1) receptors is dependent, at least in part, on the simultaneous activation of D(1) dopamine receptors. While the mechanism underlying this interaction remains to be determined, it does not appear to involve an intramembrane interaction between A(1) and D(1) receptors.

An increased incidence of dislocation is the most important potential disadvantage introduced by the use of meniscal-bearing prostheses. The aim of this in vitro study was to measure the resistance to dislocation of a meniscal-bearing total knee arthroplasty in various circumstances and to establish which anatomic structures contribute to bearing stability. The prosthesis was implanted into cadaver knee specimens mounted in a 6 df rig. Dislocation was provoked by applying anteriorly or posteriorly directed forces (20-100N) to the tibia in the plane of the tibial plateau. Dislocation was defined as any stable displacement of the bearing (relative to the tibia or the femur) that persisted after release of the load applied to provoke it. The specimens were tested in an arc of knee flexion between 30 degrees and 90 degrees, with and without simulated quadriceps loads, with and without abducting and adducting loads, and before and after division of the posterior cruciate ligament and the lateral retinaculum. In the presence of quadriceps load, dislocation could not be provoked. In the absence of quadriceps load, dislocation was not provoked by posteriorly directed force but sometimes was caused by anteriorly directed force. All but 1 of the dislocations were unicompartmental, the lateral compartment proving much less stable than the medial. The tendency toward dislocation increased from 30 degrees to 60 degrees and from 60 degrees to 90 degrees of knee flexion. Adducting moments applied to the knee caused lift-off of the lateral femoral condyle from the bearing and increased the tendency toward dislocation. Abducting moments had the opposite effect. Division of the posterior cruciate ligament had no significant effect. Division of the lateral retinaculum increased the tendency toward dislocation. A femoral component that can be implanted without lateral release is desirable.

It is now clear that IL-1 beta has profound and complex actions in the CNS. At pathophysiological concentrations it has an inhibitory effect on LTP in many regions of the hippocampus. There is also evidence emerging for a physiological role for IL-1 beta in the brain. Table 1 summarizes the effects of IL-1 beta and some other pro-inflammatory cytokines in the CNS.

Many designs of unicompartmental knee replacement show early and mid-term failure due to polyethylene wear. We studied the wear rate of congruent polyethylene meniscal bearings retrieved from failed Oxford unicompartmental knee replacements. We examined 16 bearings, 0.8 to 12.8 years after implantation, measuring their thickness and comparing it with that of 14 unused bearings. The mean rate of penetration, which included the effects of wear at both upper and lower surfaces, was 0.036 mm per year (maximum 0.08). Bearings as thin as 3.5 mm wore no faster than thicker models, but ten with evidence of impingement had greater wear. The six bearings with no impingement showed a mean rate of penetration of 0.01 mm per year. In unicompartmental knee replacement, careful implantation of fully congruous meniscal bearings can avoid failure due to polyethylene wear.

Retrieval studies have shown that the use of fully congruent meniscal bearings reduces wear in knee replacements. We report the outcome of 143 knees with anteromedial osteoarthritis and normal anterior cruciate ligaments treated by unicompartmental arthroplasty using fully congruous mobile polyethylene bearings. At review, 34 knees were in patients who had died and 109 were in those who were still living. The mean elapsed time since operation was 7.6 years (maximum 13.8). We established the status of all but one knee. There had been five revision operations giving a cumulative prosthetic survival rate at ten years (33 knees at risk) of 98% (95% CI 93% to 100%). Considering the knee lost to follow-up as a failure, the 'worst-case' survival rate was 97%. No failures were due to polyethylene wear or aseptic loosening of the tibial component. One bearing which dislocated at four years was reduced by closed manipulation. The ten-year survival rate is the best of those reported for unicompartmental arthroplasty and not significantly different from the best rates for total knee replacement.

Using a new, non-invasive method, we measured the patellofemoral force (PFF) in cadaver knees mounted in a rig to simulate weight-bearing. The PFF was measured from 20 degrees to 120 degrees of flexion before and after implanting three designs of knee prosthesis. Medial unicompartmental arthroplasty with a meniscal-bearing prosthesis and with retention of both cruciate ligaments caused no significant change in the PFF. After arthroplasty with a posterior-cruciate-retaining prosthesis and division of the anterior cruciate ligament, the PFF decreased in extension and increased by 20% in flexion. Implantation of a posterior stabilised prosthesis and division of both cruciate ligaments produced a decrease in the PFF in extension but maintained normal load in flexion. There was a direct relationship between the PFF and the angle made with the patellar tendon and the long axis of the tibia. The abnormalities of the patellar tendon angle which resulted from implantation of the two total prostheses explain the observed changes in the PFF and show how the mechanics of the patellofemoral joint depend upon the kinematics of the tibiofemoral articulation.

This paper attributes the high rate of high-density polyethylene (HDP) wear in many knee prostheses to incongruity of their articular surfaces. The authors discuss the anatomical and kinematic features of the knee which have led most designers to choose incongruous surfaces and review the reasons for employing free bearings, analogues of the natural menisci, to provide congruity without restriction of movement.There are theoretical reasons against employing freely mobile bearings in the absence of a functioning anterior cruciate ligament (ACL) and the authors' experience has confirmed this limitation in practice. It is concluded that, in bicompartmental replacement, the movements of the meniscal bearing should be limited in the anteroposterior direction. For unicompartmental arthritis, an unconstrained bearing can be employed if, as is usually the case, all ligaments are intact.

Inflammatory reactions in the airways are thought to play an important role in asthma pathogenesis. The goal of this work was to test prospectively the hypothesis that the pulmonary inflammatory response to segmental antigen challenge is greater in allergic asthmatic (AA) subjects than in allergic nonasthmatic (ANA) subjects. A total of 46 ragweed-allergic subjects, 27 AA and 19 ANA, took part in these studies. Subjects had normal or nearly normal pulmonary function, were on no chronic medication, and were characterized as to their skin sensitivity to intradermal ragweed injection, their nonspecific responsiveness to methacholine, and the presence (or absence) of a late asthmatic response after whole-lung antigen challenge. Subjects then underwent bronchoscopy, bronchoalveolar lavage (BAL) of a control lung segment, antigen lung challenge of a contralateral lung segment with 5 ml of a concentration of ragweed solution 100-fold higher than that required to produce a positive skin reaction, and finally, BAL of the challenged segment after 24 h. AA did not differ from ANA in any inflammatory parameter measured in BAL fluid (total cells/ml, macrophages/ml, lymphocytes/ml, eosinophils/ml, neutrophils/ml, total protein, albumin, urea, or eosinophil cationic protein) 24 h after challenge. In addition, there was no relationship between nonspecific bronchial responsiveness to methacholine and eosinophils recruited to the lung by segmental antigen challenge. Rather, in both groups a marked inflammatory response was seen only in the subgroup of subjects who demonstrated a late airway reaction after whole-lung antigen challenge, regardless of disease classification.(ABSTRACT TRUNCATED AT 250 WORDS)

We compared attendance by Drug Misusers to the AccidentEmergency Departments (AE) in the greater Dublin area during September 1985 and April 1993. The study took the form of a questionnaire administered by the previously trained AE staff to attenders who were currently (within the past six months): experimenting with drugs, abusing drugs or drug dependent. Seventy three drug misusers were identified in September 1985 and 68 in April 1993. Poly substance misuse was a major feature of the 1993 survey and Benzodiazepines replaced Heroin as the major drug of misuse. There was a significant increase in the misuse of prescribed opiates, in particular morphine sulphate, methadone and DF118. Physical problems associated with drug misuse were more common in 1993 because of the new trend of crushing and injecting the morphine sulphate tablet. Patients continue to inject drugs and are poor attenders at needle exchange programmes. We feel that all doctors should exercise caution in their prescribing habits in view of the alarming increase in the misuse of prescribed medication as indicated by our figures.

The bulk of the chapters in this book will concentrate on methods of measurement of strain in bone. Bone forms only part of the musculoskeletal system; the skeleton is stabilized and enabled to transmit loads by the application of muscle forces. Muscles have two primary mechanical functions; they stabilize the skeleton by preventing movement at the joints and they induce movements at the joints against the resistance of the external loads. Borelli (1679) demonstrated that the lever-arms of the muscle forces about the joints are often smaller than those of the external loads so that the muscle forces can be large, the muscles acting at a mechanical disadvantage. As a consequence, the contact forces applied by one bone to the other across the joints in reaction to the muscle forces are also large.

Laser ablation and bipolar coagulation have been used to palliate rectal cancer and avoid surgery. Indications are distal metastatic disease, extensive local invasion, obstruction and bleeding from nonresectable rectal tumor, or refusal of surgery. From Jan 1, 1986, to Jan 1, 1989, I saw 26 patients who met those criteria; 19 already had metastatic disease and three repeatedly refused abdominoperineal resection. A two-laser approach using both CO2 and Nd:YAG lasers was used in patients with low-lying lesions; others were treated by the Nd:YAG laser only. For rectal tumors, bipolar esophageal tumor probes were used via the rigid sigmoidoscope. The number of laser sessions averaged three per patient, and the number of bipolar coagulation sessions averaged five per patient. Bleeding followed bipolar coagulation in one patient. There were no perforations in either treatment group, and no patient has required colostomy. Of the 19 patients who already had metastatic disease, 12 are still alive, the longest survival being 20 months. Of those medically unfit for surgery, three have died of coincidental disease, and one is alive with controlled rectal cancer after 16 months. All three patients who refused surgery are alive; the longest survival is 13 months.

A two-dimensional mathematical model of the knee is used with gait analysis to calculate muscle, cruciate ligament and tibio-femoral contact forces developed at the knee during normal level walking. Ten normal adult subjects—four females and six males—participated. The knee model is based upon a four-bar linkage comprising the femur, tibia and two cruciate ligaments. It takes account of the rolling and sliding of the femur on the tibia during flexion/extension and the changes in direction of the ligaments and muscle tendons. We considered forces transmitted by six elements: quadriceps, hamstrings, gastrocnemius, anterior and posterior cruciate ligaments, and tibio-femoral contact. The equations of mechanics can be used to determine the absolute values of only three of the knee forces simultaneously, so that twenty limiting solutions of three of the six forces were considered. A limiting solution was rejected if any of the three forces were negative, corresponding to compressive muscle or ligament forces, or tensile contact forces. These constraints always reduced and at times removed the redundancy of the knee structures. The high incidence of predicted single muscle activity, supported by electromyography, suggested that the ligaments play a significant role in load transmission during gait. The temporal patterns of muscle and ligament activity and ligament force magnitudes were sensitive to the choice of model parameters. The analysis showed that each of four possible minimum principles of muscle selection—minimal muscle force, muscle stress, ligament force and contact force—was unlikely to be valid throughout the walking cycle.

A prototype automated system using fluorescent antibody (FA) was evaluated for rapid detection of salmonellae in foods. Samples were enriched in selenite cystine and tetrathionate broths. After incubation, both were transferred into fresh selenite cystine for a 4-h "post-enrichment" to dilute possible background fluorescence from product. These cultures were then analyzed automatically, and results were compared with those obtained by the methods of the Association of Official Analytical Chemists (AOAC). Initially, 167 samples of milk powder, dried yeast, and imported frog legs were examined. The AOAC and automated FA methods correlated well with all samples but frog legs. Difficulty with the latter was caused by procedural and mechanical problems coupled with high numbers of competing microorganisms in post-enrichment cultures. Modification of procedure and partial redesign of equipment corrected these difficulties, and excellent correlation was obtained with another 116 frog leg samples. All 89 AOAC-confirmed positives were also detected by the automated FA method, and there were only 4% false FA positives. The system shows potential for screening products for salmonellae; however, all positives should be confirmed by manual biochemical and serological methods.

The Small Office Network Data System (SONDS) is a part of the Total Network Data System (TNDS) designed specifically to meet the network data requirements for the small step-by-step offices of the Bell System. Its ability to accurately relate to the load and service characteristics seen in these small, mostly rural offices has ensured its success. It maintains low cost by measuring and recording a single observation per day for each traffic measurement. This is the daily peak hour load per group. A moving average of the mean and variance of peak hour measurements is interpreted by using a modified-Gumbel extreme value distribution function. This has been demonstrated to fit well within the actual distributions of daily peak hour loads. It is used to construct traffic capacity tables that better reflect customers service experience in these offices than do existing methods. It uses field-tested parameter assumptions of the underlying distribution from which peak values are sampled to estimate equivalent time-consistent busy hour loads relative to the observed peak hour loads. This allows service to be compared among SONDS and non-SONDS step-by-step offices. SONDS uses on-site data collection units, a single central computer for all Bell System offices, and provides local printing of output reports. Data are collected each night and daily, weekly, and monthly output reports are distributed over the switched network.