cssi/SciSciGPT-SciSciNet huggingface dataset:
Quantifying gait impairment in multiple sclerosis using GAITRite technology.

Abstract This pilot study investigated the validity of the functional ambulatory profile (FAP) score from the GAITRite™ electronic pathway in persons with multiple sclerosis (PwMS) who had onset of walking impairment. Thirteen PwMS who had Expanded Disability Status Scale (EDSS) scores of 4.0–6.0 performed four trials on GAITRite™ pathway, and completed a multidimensional walking assessment including performance tests (timed 25 foot walk; T25FW, timed up and go; TUG), self reports of walking ability (Multiple Sclerosis Walking Scale-12; MSWS-12) and function (Late Life Function and Disability Inventory; LL-FDI), and free-living walking behavior (accelerometry). The FAP score correlated strongly with neurological disability (EDSS, ρ = −0.81), walking performance (T25FW, ρ = −0.82; TUG, ρ = −0.88) and self-reported walking function (LL-FDI, ρ = 0.81), and moderately with self-reported walking impairment (MSWS-12, ρ = 0.49) and free-living walking behavior (accelerometry, ρ = 0.52). This suggests that the FAP score is a valid marker of gait impairment in PwMS who have onset of walking impairment.
Alcohol use among HMO patients in the emergency room, primary care and the general population

Objective: Although heavy drinking and alcohol-related problems are overpresented among patients seen in some primary care settings compared to the general population, it is not known whether those seen for noninjury problems in emergency rooms (ERs) are similar in demographic and drinking characteristics to those seen in primary care clinics. Nor do we know whether alcohol-related problems are over-represented in both of these settings compared to the general population when equal access to health care services is provided, as by membership in the same HMO. Reported here are data from a single northern California health maintenance organization (HMO). Method: Probability samples of noninjured patients seen in the ERs of the HMO (n = 579) are compared on demographic characteristics and drinking patterns and problems to those seen in the primary care clinics of the same HMO (n = 295) and to those in the general population of the same county who reported membership in the HMO (n = 737). Results: No differen...
Adrenal function in female rats before puberty: the effects of gonadectomy.

Abstract The following study was designed to test whether the change in the amplitude of the adrenal rhythm and the response to stress seen at puberty in female rats is dependent upon stimulation of the adrenal system by gonadal steroids. Rats were gonadectomized either at two days of age or at 21 days of age and periodic blood samples were taken by cardiac puncture and assayed for corticosterone (B) by a fluorometric procedure. Ovariectomy at weaning age (21 days) had no effect on adrenal function until the time of normal puberty onset. In intact animals, a rise in resting levels of corticosterone and an increase in the incremental response to ether stress was noted at 35 days of age. (Puberty in females was 35.3 ± 1.2 days as indicated by vaginal opening). Ovulation occurred the following day in 9/10 rats. Gonadectomy at two days of age had essentially the same effect as later gonadectomy in females. By 70 days of age, resting corticosterone values and stress responses in gonadectomized females reached levels similar to intact females. It is concluded that an independent adrenarche can occur in females but that gonadal steroids present at the time of puberty modulate the timing of this process.
Glomerular thrombosis predicts progression of glomerulonephritis: Can we prevent progression?

The evidence for the important role of coagulation in the genesis and perpetuation of glomerular injury in diffuse proliferative lupus glomerulonephritis is reviewed. The importance of early detection is emphasized, so that treatment can be started before irreversible glomerular injury has occurred. Urinalysis and simple tests of renal function are effective means of early detection.
Electrokinetic Behavior of Cylindrical Nanowires in Microfluidic Channels

Nanowires, literally wires with nanometer-scale diameters and lengths of several microns up to tens of microns, have recently garnered significant attention given their potential applications within the fields of electronics and sensing [1], among others. Nanowires can be fabricated from a diverse set of materials including metals and semiconductors, and functionalized or tailored for a range of applications (e.g. detection of specific biological or chemical species [2]). One of the key issues for integration of nanowires into electronic or sensing devices is the controlled separation, delivery, and placement of nanowires with a high degree of accuracy. Electrokinetic control of the motion of gold nanowires with both negligible and negative surface charge is demonstrated inside of fluid-filled glass microchannels. The electroosmotic and electrophoretic velocities of the nanowires are measured and compared to theoretical predictions for cylindrical particles in suspension.Copyright © 2004 by ASME
Analysis of adaptive streaming for hybrid CDN/P2P live video systems

Most commercial video streaming systems rely on Content Distribution Networks (CDNs) to distribute video content. HTTP adaptive streaming has been recently adopted by major video streaming providers and is now considered the standard technique used with CDN-based streaming systems. Despite the success of these systems, cost-effective scalability continues to be of concern in their design and deployment. To address this, recent work has proposed the use of hybrid CDN and Peer-to-peer (P2P) live streaming systems. The design of these systems aims to combine the scalability of P2P systems and the desirable performance properties of CDN-based systems. However, the use of adaptive streaming, has not been explored extensively in such hybrid systems. Designing and operating an adaptive hybrid streaming system is very challenging. Two design decisions are very critical in the operation of any such system. The first one is the bitrate adaptation strategy which specifies how different bitrates are assigned to different users while maximizing user satisfaction. The second is defining the operational guidelines for switching the system between the CDN and the P2P modes while efficiently utilizing the available resources. In this paper we present a model and analysis of a hybrid CDN-P2P adaptive live streaming system with the objective of answering these two design questions. We first present a stochastic fluid model to the hybrid streaming system with a single video bitrate and we obtain theoretical results to guide the system operation as described above. We then extend the analysis to the adaptive streaming case with multiple video bitrates. We model adaptive streaming as a linear optimization problem to obtain the best bitrate adaptation strategy. We validate our analysis using simulations. Our conclusion is that adaptive hybrid streaming can significantly improve the ability of the system to satisfy more users with higher video bitrates over CDN-based systems.
Outcome of pregnancies complicated by idiopathic intracranial hypertension

Objective: Idiopathic intracranial hypertension, also known as pseudotumor cerebri, is relatively uncommon in the general population, but has an increased incidence in reproductive-aged women. We sought to determine the obstetric and neurosurgical outcomes of pregnant women with idiopathic hypertension. Methods: Sixteen consecutive pregnancies complicated by idiopathic intracranial hypertension between January 1990 and July 1999 were included in this retrospective study. The frequency of symptoms of increased intracranial pressure and adverse obstetrical outcomes were determined in these patients. The χ2 test was used for statistical analysis. Results: Of 16 patients, 12 (75%) had a BMI ≥ 29 kg/m2. Two patients had a cerebrospinal fluid shunt (ventriculo-peritoneal in one, lumbo-peritoneal in the other). Four pregnancies ended in therapeutic abortion, one of which was prompted by severe progressive disease. Of the 12 patients whose pregnancies progressed to viability, 5 (42%) experienced worsening of their symptoms, at a mean gestational age of 10 ± 1.1 weeks. There were two perinatal deaths: one stillbirth from abruptio placentae at term and one neonatal death following the birth of a growth-restricted 29-week fetus. Both patients with a cerebrospinal fluid shunt experienced poor obstetric outcome—need for therapeutic abortion in one and term fetal demise in the other. In the nonshunted patients, there was one neonatal death (2/2 versus 1/14 poor obstetrical outcome in shunted versus nonshunted patients, P <0.05). No patients had exacerbation of symptoms during labor or the puerperium. Conclusions: An association with obesity was observed. Symptom recurrences were common, but usually responded well to conservative therapy. There may be an association between adverse pregnancy outcome and prior placement of a cerebrospinal fluid shunt.
A self-consistent polycrystal model for the spontaneous polarization of ferroelectric ceramics

Motivated by the observation that the spontaneous polarization process of a ferroelectric polycrystal under the influence of a superimposed stress and/or electric field involves heterogeneous evolution of the ferroelectric phase among its constituent grains, a selfconsistent electromechanical model is developed to determine the effective behaviour of the polycrystalline ceramic from such a heterogeneous electromechanical state. We start out from consideration of a micromechanics-based thermodynamic process to establish the kinetic equation of the crystallite and use it to evaluate the evolution of its ferroelectric domain. Then together with the Curie–Weiss law for the dielectric constants of the tetragonal phase, a dual-phase mixture theory is adopted to determine the change of its electromechanical moduli as temperature cools down below its Curie point. The overall property of the polycrystal is subsequently calculated by the self-consistent model through orientational average over its constituent grains. This two-level micromechanics model is applied to examine the shift of Curie temperature and evolution of the effective electromechanical moduli of a BaTiO3 ceramic under cooling. The calculated results show that its Curie temperature decreases with increasing hydrostatic pressure, but increases with a superimposed axial compression or a biased electric field. The predicted temperature shift and change of the dielectric constants are found to be consistent with experimental observations.
Determining the Impact of Gender and Age on Drivers' Acceptance of Graphic-Aided Portable, Changeable Message Signs in Highway Work Zones

Graphic-aided, portable, changeable message sign (PCMS) is an innovative, temporary traffic control device that has been proven in recent studies to improve drivers' response more effectively than the traditional text-based PCMSs. This study investigated the impact of drivers' gender and age on their acceptance of using graphic-aided PCMSs in highway work zones. A total of 429 driver surveys were conducted in a real-world highway work zone traffic condition under three graphic-aided PCMSs with different settings. Chi-square tests of independence were used to determine the relationship between drivers' gender and age and their preferences to message format. The results revealed that drivers' gender and age did not have a significant impact on their preferences to message format. The results also suggested that the majority of drivers preferred to see the warning messages displayed on PCMSs in the graphic-aided format instead of the traditional text format in highway work zones. This study provided valuable knowledge to government agencies and the transportation industry on the use graphic-aided PCMSs in highway work zones.
Effectiveness of a Polysubstance Dependence Detoxification Protocol for Patients With Co-occurring Disorders

Patients with polysubstance dependence and co-occurring psychiatric and substance use disorders represent a growing population. This study investigates the safety and effectiveness of a single-scale, symptom-triggered protocol for patients undergoing inpatient detoxification from alcohol, opioids, sedatives, or polysubstance dependence. Medical records staff generated a list of all charts containing a principal discharge diagnosis of alcohol, sedative, opioid, or polysubstance dependence between 2002 and 2004, when the Butler Instrument for Withdrawal Assessment protocol was administered. This list was arranged by terminal digits of the medical record numbers to randomize the selection, and staff pulled the first 100 charts for review. De-identified medical data were recorded from the charts to obtain information about medications, length of stay, and adverse events during hospitalization. The main outcome measures were adverse events and length of stay. The average length of stay was 4.2 days (SD = 2.3),...
Implications of cognitive research for ambulatory care education.

Research in cognitive psychology has led to changes in how educators conceptualize thinking and approach improving students' thinking processes. As medical education moves into ambulatory care settings, there is an opportunity for educators to consider the implications of cognition theories for the
Formation of nanoscale size cadmium sulfide within a channel protein monolayer

Abstract The size, structure and ease of manipulation of organized monolayer structures have been used to control reaction pathways for the formation of semiconductor particle clusters of cadmium sulfide and other semiconductors. The size and particle distributions are determined by the specific monolayer structure chosen. The present study reports a new technique for the formation of small clusters of cadmium and zinc sulfides. It combines monolayer methods with techniques based on inclusion formation in restricted volumes. Cadmium and zinc sulfides are formed within the cavity of a channel protein by a simple process in which a close-packed monolayer of the channel protein is formed on a neutral subphase, transported to a cadmium-chloride-containing subphase, transferred to a slide by Langmuir-Blodgett transfer and exposed to hydrogen sulfide. The channel protein is a membrane-bound entity with hydrophobic exterior walls and a hydrophilic inside channel (12 A diameter). It is cylindrical and in compressed monolayers is oriented normal to the interface with the channel mouth in communication with the subphase. Small water-soluble ions are rapidly taken into the channel interior. The size of the cluster formed is limited by the small number of ions capable of assimilation into the channel and, because each group of ions is compartmentalized, there is no possibility of spontaneous aggregation to produce macroscopic particulate inside of the protein channel. The cadmium and zinc sulfides were produced in the “quantum dot” size range as evidenced by their markedly blue-shifted optical spectra. The results of this study indicate more general potential application of channel protein structures as nanoscale reactors; in the case of the protein used here the channel opening and closing can be modulated by pH changes, affording the possibility of sealing or encapsuliting reactants or products in small defined volumes. Other types of channel structure are closed by changes in potential, specific small ions or biogenic messenger molecules. Some of these have significantly larger channel volumes that the protein used here. These too may be likely future systems for specific small-scale reactions.
Towards a Plug-and-Play B2B Marketing Tool Based on Time-Sensitive Information Extraction

The LARIAT system developed at IBM Research uses information extraction applied to news feeds and other time-sensitive documents, along with historical and enterprise data, to provide a stream for B2B sales leads to different sales teams. This paper overviews the system and discusses lessons learned. LARIAT is contrasted with the IBM infoSage system from almost two decades ago. The experience with LARIAT is used as the basis for the design of a Solution-as-a-Service framework that will enable a richly extensible version of the capability, which could serve multiple B2B companies while affording economies of scale.
SLAs as an Organizational Playground for Collective Problem-Solving and Tacit Knowledge Generation

We seek to contribute to the literature by examining the spontaneous incidence of organizational play as a playground for collective tacit knowledge generation at work. Building upon the transactiv...
Machine fault tolerance for reliable datacenter systems

Although rare in absolute terms, undetected CPU, memory, and disk errors occur often enough at datacenter scale to significantly affect overall system reliability and availability. In this paper, we propose a new failure model, called Machine Fault Tolerance, and a new abstraction, a replicated write-once trusted table, to provide improved resilience to these types of failures. Since most machine failures manifest in application server and operating system code, we assume a Byzantine model for those parts of the system. However, by assuming that the hypervisor and network are trustworthy, we are able to reduce the overhead of machine-fault masking to be close to that of non-Byzantine Paxos.
The Subjective Well-Being of Nations: A Role for Marketing?

In this study, the authors test a conceptual model that explains the subjective well-being (SWB) of nations. The authors include traditional predictors (e.g., human rights) and marketing variables (e.g., advertising expenditure, retailing indexes) in their model. They are especially interested to see to what extent marketing activities are associated with citizens' welfare or happiness. Using data from fifty-five countries, the authors find that one marketing variable (advertising expenditure per capita) strongly correlates with SWB, while another (number of retail outlet per capita) does not show a strong relationship with SWB. However, the strong relation fades away when other e fects are partialed out. The authors' model accounts for a large amount of variance in SWB. However, the e fect of marketing variables in a multivariate setting is not particularly strong.
Altered myocardial force-frequency relation in human heart failure.

BACKGROUNDIn congestive heart failure (idiopathic dilated cardiomyopathy), exercise is accompanied by a smaller-than-normal decrease in end-diastolic left ventricular volume, depressed peak rates of left ventricular pressure rise and fall, and depressed heart-rate-dependent potentiation of contractility (bowditch treppe). We studied contractile function of isolated left ventricular myocardium from New York Heart Association class IV-failing and nonfailing hearts at physiological temperature and heart rates in order to identify and quantitate abnormalities in myocardial function that underlie abnormal ventricular function.METHODS AND RESULTSThe isometric tension-generating ability of isolated left ventricular strips from nonfailing and failing human hearts was investigated at 37 degrees C and contraction frequencies ranging from 12 to 240 per minute (min-1). Strips were dissected using a new method of protection against cutting injury with 2,3-butanedione monoxime (BDM) as a cardioplegic agent. In nonfaili...
Detailed Cadaveric Simulation of Landing Reveals Timing Sequence of Multi-Planar Knee Kinematics: Implications for ACL Injury

Over 120,000 anterior cruciate ligament (ACL) injuries occur annually in the United States, mainly affecting the young athletic population. Non-contact injuries are reported to be the predominant mechanism of ACL injury (>70% of ACL injuries), which often occur during landing with high ground reaction forces, muscle forces and segmental inertia. An improved understanding of the mechanisms underlying non-contact ACL injury and inciting events can be used to improve current prevention strategies and decrease the risk of early-onset osteoarthritis. Previous biomechanical and video analysis studies have demonstrated that anterior tibial translation (ATT), knee valgus and internal tibial rotation (ITR) are associated with non-contact ACL injuries [1–3]. While the effects of these factors on ACL injury risk have been extensively studied, there is still controversy and debate about the timing in which these motions occur and reach maximum values during a jump landing task. The current study aimed to investigate interactions between tibio-femoral joint kinematics and ACL strain through a detailed cadaveric simulation of the knee biomechanical response during landing from a jump. For this purpose, instrumented cadaveric limbs were used to simulate bi-pedal landing following a jump utilizing a novel testing apparatus.Copyright © 2013 by ASME
Transesophageal echocardiography in critical care units: Henry ford hospital experience and review of the literature

Transthoracic echocardiography is of limited value in intensive care units primarily because of mechanical ventilators, surgical wounds, and the inability to position the patient to his left side. Imaging from the transesophageal window overcomes these problems, resulting in good-quality study in these patient subsets. We performed both transthoracic and transesophageal echocardiography with color-flow Doppler tests in 121 patients in various critical care units. The transesophageal ultrasound test was valuable in identifying patients with suspected left-sided native and prosthetic valve vegetations, prosthetic mitral but not aortic valve regurgitation, native mitral and aortic valve pathoogy, and aortic dissection and in determining cardiac etiology of systemic emboli, hypotension, hypoxia, and heart failure. Based on transesophageal echocardiographic findings, additional information was provided in 38 (32%) patients, resulting in appropriate surgery in 22 instances. In conclusion, transesophageal echocardiography is a useful tool in evaluating critically ill patients.
Incorporating soft skills into accounting and MIS curricula

Faculty face many challenges both in and outside the confines of the university setting. They must increase the number of topics and the depth in which the material is covered while simultaneously reducing the number of required degree hours. In addition, employers have acknowledged an overall decline of soft skills among today's graduates. Further, faculty must address their material coverage for the multi-tasking skills of today's college students. In this article, the authors address the concerns voiced by the employers of college graduates regarding the apparent absence of soft skills competence and suggest an assurance of learning model for incorporating these skills into curricula.
The Effects of Computer Based Resource Units upon Instructional Behavior

Computer based resource units were developed to improve the individualization of instruction through unit teaching. Instructional behaviors of teachers were examined to see if this kind of computer aid brought about a change in the way teachers teach. A pre-post two group experimental design was used in which the data were collected by a group of trained observers using an instruction observation tool. Pre-post mean scores were tested and found to be significant in five out of seven dimensions of instructional behavior. Variety and kinds of instructional materials and methods were also examined. The data indicate that teachers who use computer based resource units increase the number and improve the quality of many individualized instruction tasks.
A randomized study of two different schedules of methyl CCNU, 5-FU and vincristine for metastatic colorectal carcinoma.

Sixty-seven patients with measurable colorectal carcinoma were randomized to receive two different schedules of Methyl CCNU, 5-FU and Vincristine (MOF). The treatment schedule consisted of Methyl CCNU 150 mg/m2 po q 70 days, 5-FU 300 mg/m2 iv for 5 consecutive days q 35 days, and Vincristine 1 mg/m2 IV q 35 days. The same total dose was used in each arm; in MOF A, the Methyl CCNU was given on day 1, while in MOF B, the Methyl CCNU was divided and given over 5 consecutive days. In MOF A, there was a 10% partial response rate and a 10% minor response rate. In MOF B, the partial response rate was 12% and the minor response rate was 21%. This difference is not statistically significant, but the patients in MOF B experienced less gastrointestinal toxicity (p less than .001).
Characterization of an influenza A host range mutant.

Abstract A mixed infection of primary chick kidney cells at 38° with A/Ann Arbor/6/60 cold adapted virus and A/Alaska/6/77 wt virus yielded a cold-reassortant virus, CR43-clone 3, which had a host range different from that of either parent. It does not produce detectable virus when grown in Madin-Darby canine kidney cells, while growing normally in primary chick kidney cells at 33°. Both parents, however, grow well in either cell type at 33°. Genotypic analysis of viral RNA electrophoresed in polyacrylamide gels has shown that CR43-clone 3 virus has an aberrant NS gene different from the NS gene of either parent virus. Reassortant viruses made between CR43-clone 3 virus and A/California/ 10/78 (H1N1) virus in primary chick kidney cells at 33° showed the same host range restriction only if the NS gene was derived from the CR43-clone 3 virus. A mixed infection with these same parents, but in Madin-Darby canine kidney cells at 33°, produced reassortants that always contained the A/California/10/78 NS gene instead of the CR43clone 3 NS gene. Ferrets inoculated intranasally with the CR43-clone 3 reassortant do not become sick or infected, based on the lack of symptoms: no rhinitis, coryza, or fever; and no detectable virus recovered from nasopharyngeal swabs, turbinate, or lung tissues at 48 hr after infection. Thus, CR43-clone 3 virus contains an aberrant NS gene and manifests a restricted host range phenotype in Madin-Darby canine kidney cells and ferrets.
Histopathology and surgical anatomy of patients with primary hyperparathyroidism and calcium phosphate stones

Using a combination of intra-operative digital photography and micro-biopsy we measured renal cortical and papillary changes in five patients with primary hyperparathyroidism and abundant calcium phosphate kidney stones. Major tissue changes were variable papillary flattening and retraction, dilation of the ducts of Bellini, and plugging with apatite deposits of the inner medullary collecting ducts and ducts of Bellini. Some of the papillae in two of the patients contained plentiful large interstitial deposits of Randall's plaque and where the deposits were most plentiful we found overgrowth of the attached stones. Hence, this disease combines features previously described in brushite stone formers – dilation, plugging of ducts and papillary deformity – with the interstitial plaque and stone overgrowth characteristic of routine idiopathic calcium oxalate stone formers, suggesting that these two patterns can coexist in a single patient.
Can sharp seismic discontinuities be caused by non-equilibrium phase transformations?

A long-posed problem of the seismic discontinuities at the depths of 410 and 660 km in Earth's mantle is whether these discontinuities are caused by phase transitions alone or together with chemical layering. Among several tests, the sharpness of the boundary is one of the most crucial. Recent data suggest that the transition region thickness is less than 4 km for both the 410 and the 660 km discontinuities. This may be smaller than predicted by phase equilibria. We suggest that if there is a sufficiently large nucleation barrier for phase transformation and if the transformation front cannot move faster than the convective flow, the transformation in rising or descending material does not take place until the metastable overshoot becomes equal to the nucleation barrier. An avalanche-like transformation following this overshoot occurs in a very narrow region and can be the cause of a sharp seismic discontinuity. In this case, the topography of the phase boundary is also substantially modified.
Trifluoromethyl group in the synthesis of heterocyclic compounds: New and efficient synthesis of 3-aryl-4-aminocinnolines

Abstract A novel base-induced transformation of hydrazones 3a-f derived from trifluoromethylaryl ketones and arylhydrazines was found to produce 3-aryl-4-aminocinnolines 4a-g in 52–75% yield. The initial step of the reaction is believed to involve abstraction of HF from hydrazone.
Compliance issues and homeland security with new federal regulations for higher education institutions

This chapter discusses new guidelines for chemical hazardous materials for homeland security compliance and the role institutional research has in these compliance mandates.
Electrons as the cause of the observed dmax shift with field size in high energy photon beams.

For megavoltage x-ray beams, it is well known that the percent depth-dose increases considerably with field size in the buildup region, resulting in a significant shift in the apparent position of maximum dose, d/sub max/. The nature of this increase has been investigated using a sweeping magnet placed just below the treatment head of a 25-MV linac. Measurements show that for increasing magnetic fields the dose in the buildup region is continually reduced, until a point is reached beyond which no additional reduction is observed. Here the buildup curve is essentially field size independent. These results clearly show that electrons are the primary cause of dose increase with field size in the buildup region, in contrast to a recent publication claiming that scattered photons are the cause. Further measurements were made by blocking out the primary beam at the level of the jaws and measuring the depth dose of the scattered electrons originating from the jaws. The results show that a thickness of approximately 1 g cm/sup -2/, of either polystyrene or lead, reduces the dose by a factor of two, providing further evidence that the scattered component of the beam consists of low energy electrons.
Increased Duration and Sample Attrition in New York City′s Rent Controlled Sector

Abstract This paper shows that between 1978 and 1987 tenants living in New York City′s strict rent controlled sector were less mobile than those living in the city′s moderate rent stabilized sector. However after taking into account differences in tenant characteristics across section, one cannot conclude that typical renters in the controlled sector would move more often if they lived in the other sector. Controlled sector tenants tend to be white and relatively old, which are characteristics associated with immobility. If is like that the 1971 Vacancy Decontrol Act, through attrition, divided tenants into the two sectors by their characteristics.
An investigation of the L 2 - L 3 Coster-Kronig transition probability for 63≦ Z≦96

The total transition probabilityf 23 for theL 2-L 3 Coster-Kronig transition probability atZ=80, 81, 82, and 92 was measured withL α x-ray coincidences between high resolution Si(Li) and Ge(HP) x-ray detectors and a dual-parameter multichannel coincidence system. TheL α gating technique for observing theK x-ray coincidence spectrum was carefully checked and found to be equivalent to the method of observing theL x-ray spectrum with $$K_{\alpha _{1,2} } $$ gates, when proper corrections are applied. The values off 23 found are 0.123±0.012, 0.109±0.011, 0.105±0.011, and 0.146±0.018 atZ=80, 81, 82, and 92, respectively. These values, together with all previously published values in the region 57≦Z≦96, are critically evaluated and a group of “best values” selected for comparison with theory. The agreement is quite good in the region 63≦Z≦83. The independentparticle model employing a Green-Sellin-Zachor potential used by Chen and Crasemann predicts values off 23 which are too large compared with experiment in the high-Z region, whereas the theoretical predictions of McGuire using an approximate Herman-Skilman potential are too low. However, the screened nonrelativistic hydrogenic results of Chen, Crasemann, and Kostroun are in satisfactory agreement with the experiments. The experimental result atZ=92 indicates that theL 2-L 3 M 4 transition is at or below threshold and contributes little or no intensity to the value of f23.
Estimating the probability of a diffusing target encountering a stationary sensor

Abstract : In this report two expressions are given for the probability of a diffusing target avoiding detection to time t by a sensor fixed at the center of a square region A. The target is constrained to always remain within A. The first expression results from an approximation to the exact solution of the diffusion equation, and the second from experimentation with a Monte Carlo simulation of the diffusion process.
Asymmetry of dynamics at the growing crystal-melt interface

Dynamic light-scattering measurements on the $b$ face of a salol crystal growing into the melt revealed simultaneous lateral translation dynamics on the crystal surface and slow relaxational dynamics in a thin boundary layer of melt adjacent to the crystal. Analysis of the translational dynamics shows that crystal growth is mediated by highly polygonized screw dislocations. An explanation is suggested for the relaxational dynamics based on the dynamics of nematic liquid crystals.
Computer simulation of protein crystal growth using aggregates as the growth unit

We present results of a computer simulation of protein crystal growth based on the Monte Carlo random process and surface kinetics of a growing crystal, which includes site-dependent detachment and migration, and site-independent attachment processes. The results indicate that, if only monomers are included in the attachment process, the simulation does not reproduce the experimentally observed rate of growth of lysozyme crystals at high supersaturation; however, using the same simulation parameters but allowing both monomers and aggregates to become attached to the crystal surface simulates the experimental results both at low and at high supersaturation. The results suggest possible influences of protein aggregates on the crystallization process.
Neonatal intracranial hemorrhage: II. Risk factor analysis in an inborn population

The ability to predict the occurrence of neonatal periventricular-intraventricular hemorrhage (PVH-IVH) would be useful in the design of clinical trials to prevent its occurrence. Therefore, data were collected from 463 consecutive infants ⩽1500 g birth weight delivered between March 1, 1982 and February 28, 1985. This large population made it feasible to divide the infants into two groups, using one group to develop a model predictive of ICH and the second group to test the validity of the model. Infants were randomly grouped by sex, race, gestational age, birth weight, month of birth, mortality, and incidence and grade of worst PVH-IVH. In Group A (n = 232), respiratory distress syndrome, ventilator therapy, PaCO2 ⩾ 60 mmHg, Po2 ⩽ 40 mmHg ⩾ 2 h, lower 1- and 5-min Apgar scores, lower pediatric estimation of gestational age, and pneumothorax were significantly associated with PVH-IVH by univariant analyses (χ2, P < 0.03). Multivariant discriminant analysis performed on Group A revealed that pneumothorax, cesarean section, PaCO2, and ventilator therapy were most predictive of PVH-IVH, but sensitivity was 55% and specificity 78%. Applying the model to Group B, sensitivity decreased to 21% while specificity rose to 93%. Logistic regression, which takes into account non-normally distributed variables, did not improve predictability. Although the clinical factors associated with the occurrence of PVH-IVH in our large inborn population of low-birth-weight infants do not differ from earlier reports, we were unable to develop an adequate model predictive for PVH-IVH. Thus, many of these factors may be associations rather than causative.
Debris flows in Glacier National Park, Montana: geomorphology and hazards

Abstract Debris flows are one of the many active slope-forming processes within Glacier National Park, Montana. Most debris flow landforms exhibit classic morphology with a distinct failure scarp, incised channel, channel levees, and toe deposits that often develop a lobate form. The Precambrian metasediments that dominate Glacier National Park's geology weather into angular clasts that range in size from platy gravels to boulders. Classic debris flows occur in areas where the topographic expression provides a debris source from cliff faces and an accumulation of regolith, often in the form of talus slopes. Many of these debris flows have long runout zones and can travel many hundreds of meters. Often they cross hiking trails or roads, including the main east–west highway, Going-to-the-Sun Road. Debris flows impacting the road have resulted in several near fatalities, and hikers have been forced to cross active debris flows to reach safe ground. The magnitude of debris flows varies between high magnitude channel incising events and low magnitude channel filling and/or reworking events. The frequency of debris flow events is irregular and appears to be controlled by the hydrology of triggering storms and antecedent moisture conditions, not by the debris supply. As a result, debris flow magnitude is not a function of frequency, but is more closely related to the characteristics of antecedent conditions and individual storms.
Histamine in the CNS: Multiple functions and potential neurologic implications

The source of histamine in the CNS is the tuberomammillary nucleus (TMN) of the hypothalamus, which provides widespread innervation to the forebrain, brainstem, and spinal cord. Histamine, acting via H1, H2, and H3 receptors, controls neuronal excitability, synaptic transmission, and synaptic plasticity, both directly and via interactions with other neurotransmitter systems. Histaminergic TMN neurons are active during wakefulness and exert multiple functions. Studies on knockout mice indicate that histamine has a major role in maintenance of arousal and contributes to modulation of circadian rhythms, homeostasis, motor behavior, and cognition. The histaminergic system is involved in narcolepsy and may also contribute to the manifestations of Alzheimer disease (AD), Parkinson disease (PD), Tourette syndrome, and other neurologic disorders. Drugs that affect histamine receptors have therapeutic potential for sleep disorders, pain, epilepsy, and cognitive disorders. These subjects have been recently reviewed.1,–,5 ### Tuberomammillary nucleus and its targets. The TMN of the hypothalamus is the sole source of histaminergic innervation of the CNS1,–,3,6,7 (figure 1). Varicose axons of TMN neurons provide widespread input to all areas of the CNS via 2 ascending pathways that innervate the hypothalamus, basal forebrain, basal ganglia, amygdala, hippocampus, and cerebral cortex; there is one descending pathway that innervates the brainstem, including the cholinergic and monoaminergic nuclei, cerebellum, and spinal cord.2 The most densely innervated target of histaminergic fibers is the hypothalamus. In humans, there is a well-organized network of histaminergic varicose fibers in the cerebral cortex, particularly in lamina I, where the fibers extend parallel to the pial surface.2 Figure 1 The brain histaminergic system The tuberomammillary nucleus (TMN) of the hypothalamus is the sole source of histaminergic innervation of the CNS. Varicose axons of TMN neurons provide widespread input to all areas of the CNS via 2 ascending pathways that innervate the hypothalamus, basal …
The mechanisms of coenzyme Q10 as therapy for myocardial ischemia reperfusion injury

It has been hypothesized that CoQ10 (CoQ) pretreatment protects myocardium from ischemia reperfusion (I/R) injury by its ability to increase aerobic energy production as well as its activity as an antioxidant. Isolated hearts from rats pretreated with either CoQ 20 mg/kg i.m. and 10 mg/kg i.p. or vehicle 24 and 2 h prior to the experiment, were subjected to 15 min of equilibration (EQ), 25 min of ischemia, and 40 min of reperfusion (RP). Developed pressure, +/-dp/dt, myocardial oxygen consumption, and myocardial aerobic efficiency (DP/MVO2) were measured. 31P NMR spectroscopy was used to determine ATP and PCr concentrations. Lucigenin-enhanced chemiluminescence of the coronary sinus effluent was utilized to determine oxidative stress through the protocol. CoQ pretreatment improved myocardial function after ischemia reperfusion. CoQ pretreatment improved tolerance to myocardial ischemia reperfusion injury by its ability to increase aerobic energy production, and by preserving myocardial aerobic efficiency during reperfusion. Furthermore, the oxidative burst during RP was diminished with CoQ. Similarly it was hypothesized that CoQ protected coronary vascular reactivity after I/R via an antioxidant mechanism. Utilizing a newly developed lyposomal CoQ preparation given i.v. 15 min prior to ischemia, ischemia reperfusion was carried out on Langendorff apparatus as previously described. Just prior to ischemia and after RP, hearts were challenged with bradykinin (BK) and sodium nitroprusside (SNP) and change in coronary flow was measured. CoQ pretreatment protected endothelial-dependent and endothelial-independent vasodilation after I/R. We conclude that CoQ pretreatment protects coronary vascular reactivity after I/R via OH radical scavenger action.
Post-intensive care unit pediatric hospital stay and estimated costs.

Objective: For pediatric intensive care unit (ICU) survivors, to determine the proportion of hospital stay and estimated hospital costs accounted for by post-ICU care. Design: Prospective study. Setting: University teaching hospital. Patients: Pediatric patients who survive an ICU admission. Interventions: None. Measurements and Main Results: Estimated relative daily costs were assumed as follows: ICU, with ventilator/ICU, not on ventilator/intermediate care unit/general pediatric hospital day, at 2:1:0.7:0.3, respectively. Estimated costs were expressed in arbitrary units as (number of days at each level of care) × (relative cost per day). The ICU phase was defined as the patient's first ICU admission only, and the post-ICU phase included intermediate care unit and general pediatric hospital days, as well as ICU readmission during the same hospitalization. Pre-ICU hospital activity was excluded from analysis. For 341 ICU survivors, post-ICU days (median, 4 days per patient) accounted for 62% of the total hospital stay. Post-ICU care accounted for one third of the total estimated hospital costs for ICU survivors. Patients with longer post-ICU stays could not be reliably identified at the time of ICU discharge according to their ICU length of stay, duration of mechanical ventilation in the ICU, age, ICU day 1 mortality probability, or diagnostic group (p> .05). Conclusions: Post-ICU care accounts for a substantial proportion of hospital stay and estimated costs for ICU survivors. These observations suggest that developing strategies to optimize hospital utilization at the time of ICU discharge may be important for controlling costs of recovery from critical illness.
Crystal structure systematics from oxide phase diagrams by contouring them with Zoltai`s tetrahedral sharing coefficient

For crystal structures of oxides with tetrahedral coordination polyhedra, the average number of tetrahedra participating in the sharing of a corner, i.e., Zoltai`s tetrahedral sharing coefficient, provides a measure of the degree of polymerization of the tetrahedra. By contouring oxide phase diagrams with Zoltai`s tetrahedral sharing coefficient, crystal structure systematics can be conveniently displayed and correlated with other physical and thermochemical properties. The advantages of this analysis are (i) a structural map guides exploration for new compounds, (ii) possible structures for existing compounds that are not known are suggested, (iii) the internal consistency of the chemistry of specific compounds is tested by structural constraints, (iv) the physical behavior and properties of a family of compounds in a chemical system can be correlated with the degree of polymerization of the tetrahedra, and (v) the analysis lends itself to computer programming, in that contour templates of tetrahedral sharing coefficients for different types of oxide systems can be easily determined and overlaid on traditional phase diagrams. Shortcomings to this approach are that the tetrahedral sharing coefficient does not define a unique tetrahedral anion topology, ambiguities arise if some of the oxygen atoms are not part of the tetrahedral anion, and many chemical systemsmore » contain oxides where one or more of the tetrahedral cations adopt other coordination geometries.« less
The reversal by phospholipid treatment of the gramicidin-induced Na+ permeability of pigeon red blood cells.

Abstract Cells made highly permeable to Na + by gramicidin treatment become nearly impermeable after treatment with phospholipid. The action of the phospholipid requires a temperature near 40 °C and has a rate-limiting step that does not depend on the phospholipid concentration. After sequential treatment with gramicidin and phospholipid, cells retain nearly full glycine transport activity.
Cigarette smoking and breast cancer risk

Evaluation of: Luo J, Margolis KL, Wactawski-Wende J et al. Association of active and passive smoking with risk of breast cancer among postmenopausal women: a prospective cohort study. BMJ DOI: 10.1136/bmj.d1016 (2011) (Epub ahead of print). Luo et al. have had the advantage of assessing active and passive smoking effects on breast cancer in 40 clinical centers in the USA involving 79,990 women aged 50–79 years, who were enrolled in the Women’s Health Initiative Observational Study from 1993 to 1998. This is the possibly the largest cohort that has demonstrated the hazards of cigarette smoking and its impact on carcinoma of the breast in women.
A model SN2 reaction ‘on water’ does not show rate enhancement

Abstract Molecular dynamics calculations of the benchmark nucleophilic substitution reaction (S N 2) Cl − + CH 3 Cl are carried out at the water liquid/vapor interface. The reaction free energy profile and the activation free energy are determined as a function of the reactants’ location normal to the surface. The activation free energy remains almost constant relative to that in bulk water, despite the fact that the barrier is expected to significantly decrease as the reaction is carried out near the vapor phase. We show that this is due to the combined effects of a clustering of water molecules around the nucleophile and a relatively weak hydration of the transition state.
Demographic Changes in Myanmar since 1983: An Examination of Official Data

According to official estimate, the total population of Myanmar reached 59.8 million in 2010. Yet, serious doubt exists on the reliability of these data. From the body of empirical evidence, best estimates of mortality and fertility are derived and serve to reconstruct prospectively the population of the country from 1983 to 2010. Despite the uncertainty regarding the levels and trends in international migration, the results are unequivocal: given the observed development in mortality and fertility, the population of Myanmar could not have reached 59.8 million in 2010. In addition to encouraging reconsideration of current population estimates, this analysis should also prompt the government and the international community to redouble their efforts in preparing for the 2014 census; carrying out a high-quality count of the entire population, ideally followed by a post-enumeration survey; conducting a thorough analysis of the census data; and publicly releasing the census results and accompanying analytical volumes in a timely manner.