Violence against children: A review of cases at a forensic anthropology unit, Johannesburg, South Africa

South Africa is experiencing a scourge of violence against women and children, with alarming levels of violence, and as such, juvenile cases are sometimes encountered in a forensic anthropological setting. The aim of this research was to assess the cases of juveniles (under 20 years) presenting at the Human Variation and Identification Research Unit (HVIRU) for a 6-year period (2016-2022), in order to assess patterns and types of cases referred. A total of 19 cases were assessed, of which 10 were 16-20 years old, 3 between the ages of 5 and 15 years and 6 less than 5 years old at the time of death. Of the 14 children with known sex, 12 were female with features suggesting that they fell prey to sexual violence. Many of the individuals were either known (and referred for trauma analysis) or identified following investigation. Of the 19 juveniles, 11 (58 %) had evidence of perimortem trauma (sharp and/or blunt), attesting to the violent nature of their deaths. Two cases had both sharp and blunt force trauma, of which one is a possible case of dismemberment. The remains of two individuals showed signs of perimortem burning, which may or may not be related to the cause of death. Three individuals had signs of antemortem (healed) trauma, which may suggest a longer period of abuse. Five of the individuals showed signs of disease - two had cribra orbitalia, while two others had various porous lesions indicative of chronic disease or malnutrition. One individual had advanced osteomyelitis, suggesting a natural cause of death. Some of these cases had unusual trauma and pathology, highlighting the contribution of forensic anthropologists.

Analysis of financial challenges faced by graduate students in Canada

Graduate students are vital to the creation of research and innovation in Canada. The National Graduate Student Finance Survey was launched in 2021 by the Ottawa Science Policy Network to investigate the financial realities of Canadian graduate students. Closing in April 2022, the survey received 1305 responses from graduate students representing various geographical locations, years of study, fields of education, and demographic backgrounds. The results capture a snapshot into graduate student finances, including an in-depth analysis of stipends, scholarships, debt, tuition, and living expenses. In its entirety, we found that the majority of graduate students are facing serious financial concerns. This is largely due to stagnant funding for students both from federal and provincial granting agencies and from within their institutions. This reality is even worse for international students, members of historically underrepresented communities, and those with dependents, all of whom experience additional challenges that impact their financial security. Based on our findings, we propose several recommendations to the Tri-Council agencies (Natural Sciences and Engineering Research Council, Social Science and Humanities Research Council, and Canadian Institute for Health Research) and academic institutions to strengthen graduate student finances and help sustain the future of research in Canada.

Patient Outcomes and Lessons-Learned from Treating Patients with Severe COVID-19 at a Long-Term Acute Care Hospital: A Single-Center Retrospective Analysis

Background

With the continuation of the COVID-19 pandemic, shifting active COVID-19 care from short-term acute care hospitals (STACHs) to long-term acute care hospitals (LTACHs) could decrease STACH census during critical stages of the pandemic and maximize limited resources.

Objective

This study aimed to describe the characteristics, clinical management, and patient outcomes during and after the acute COVID-19 phase in an LTACH in the Northeastern United States.

Methods

This was a single-center group comparative retrospective analysis of the electronic medical records of patients treated for COVID-19–related impairments from March 19, 2020, through August 14, 2020, and a reference population of medically complex patients discharged between December 1, 2019, and February 29, 2020. This study was conducted to evaluate patient outcomes in response to the holistic treatment approach of the facility.

Results

Of the 127 total COVID-19 admissions, 118 patients were discharged by the data cutoff. At admission, 29.9% (38/127) of patients tested positive for SARS-CoV-2 infection. The mean age of the COVID-19 cohort was lower than that of the reference cohort (63.3, 95% CI 61.1-65.4 vs 65.5, 95% CI 63.2-67.8 years; P=.04). There were similar proportions of males and females between cohorts (P=.38); however, the proportion of non-White/non-Caucasian patients was higher in the COVID-19 cohort than in the reference cohort (odds ratio 2.79, 95% CI 1.5-5.2; P=.001). The mean length of stay in the COVID-19 cohort was similar to that in the reference cohort (25.5, 95% CI 23.2-27.9 vs 29.9, 95% CI 24.7-35.2 days; P=.84). Interestingly, a positive correlation between patient age and length of stay was observed in the COVID-19 cohort (r²=0.05; P=.02), but not in the reference cohort. Ambulation assistance scores improved in both the reference and COVID-19 cohorts from admission to discharge (P<.001). However, the mean assistance score was greater in the COVID-19 cohort than in the reference cohort at discharge (4.9, 95% CI 4.6-5.3 vs 4.1, 95% CI 3.7-4.7; P=.001). Similarly, the mean change in gait distance was greater in the COVID-19 cohort than in the reference cohort (221.1, 95% CI 163.2-279.2 vs 146.4, 95% CI 85.6-207.3 feet; P<.001). Of the 16 patients mechanically ventilated at admission, 94% (15/16) were weaned before discharge (mean 11.3 days). Of the 75 patients admitted with a restricted diet, 75% (56/75) were discharged on a regular diet.

Conclusions

The majority of patients treated at the LTACH for severe COVID-19 and related complications benefited from coordinated care and rehabilitation. In comparison to the reference cohort, patients treated for COVID-19 were discharged with greater improvements in ambulation distance and assistance needs during a similar length of stay. These findings indicate that other patients with COVID-19 would benefit from care in an LTACH.

Measurements of public trust in the health system: mapping the evidence

Introduction

Public trust in the health system is essential to control the Covid-19 pandemic. It can influence the extent to which interventions to combat a pandemic are accepted by citizens. The objective of this review was to map the evidence of measurements of the concept of public trust in the health system with a focus on health system institutions.

Methods

We performed a systematic literature search in the databases Web of Science and Embase in March 2020. Quantitative studies measuring trust on a system level with regard to healthcare were eligible if they addressed the general public and were published in English or German. We excluded studies that measured trust on an interpersonal level, in a single health profession, or a single treatment. We extracted data to map the characteristics of measurements.

Results

Of initially 7137 identified articles, 87 studies were included in the mapping. In 58 (67%) of the studies, trust was the outcome variable. Most studies (69%) measured the level of trust with single items, 27 studies (31%) used scales or indices to measure the concept of trust. Of these, 12 studies measured healthcare system trust, 7 trust in government and political institutions, 4 trust in healthcare organisations, 3 trust in health insurances, and 1 trust in health data management institutions. Most common domains of trust in the healthcare system refer to policies, quality of services, communication and provision of information, relationships with providers and their expertise, and quality of cooperation between providers. Theoretical dimensions of the concept of trust include fidelity, competency, trustworthiness, integrity and global trust.

Conclusions

Few quantitative studies examine dimensions of public trust on a health system level. Future country-specific research on the concept of public trust may support the understanding of context-specific determinants for the tailoring of interventions to promote trust in health systems.

Key messages

Public trust is an important aspect for controlling a pandemic, as it is a precondition for accepting interventions, such as vaccination programmes. Country-specific research may promote the understanding of public trust and the tailoring of interventions to increase health system trust.

Stages of life: A new metaphysics of conceptionism

When a human being comes into existence is crucial in bioethics. Conceptionism is the view that a human being comes into existence at conception. The twinning argument is an influential objection to this view. All versions of the twinning argument rely on a metaphysics of material objects, namely, endurantism. Given this, a strategy for defending conceptionism against the twinning argument is to deny endurantism and adopt an alternative metaphysics of material objects. A version of this strategy which has been debated in this journal is to adopt perdurantism, or the 'multiple occupancy view', on which monozygotic twins share the zygote region as a temporal part. We present a novel version of this strategy: conceptionists can evade the twinning argument by adopting an exdurantist metaphysics of material objects. We suggest reasons for thinking that this is a plausible and, indeed, preferable way for conceptionists to avoid the twinning argument.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Trust and Its Role in the Medical Encounter

This paper addresses two research questions. The first is theoretical: What is trust? In the first half of this paper we present a distinctive tripartite analysis. We describe three attitudes, here called reliance, specific trust and general trust, each of which is characterised and illustrated. We argue that these attitudes are related, but not reducible, to one another. We suggest that the current impasse in the analysis of trust is in part due to the fact that some writers allude to these distinctions, but unclearly so, whilst others elide them altogether. The second research question focuses on doctor-patient interaction. Trust is often said to be central in medical encounters but this strikes us as too vague. The success of doctor-patient relations in part depends on adopting the most appropriate of the three attitudes we delineate. We argue that reliance is the appropriate attitude for most medical encounters. When circumstances do require trust, the distinction between specific trust and general trust is crucial. We describe medical encounters requiring specific trust. General trust is less often required in medicine; but it is appropriate in some cases and, when called for, it is called for strongly.

Direct detection of neural activity in vitro using magnetic resonance electrical impedance tomography (MREIT)

We describe a sequence of experiments performed in vitro to verify the existence of a new magnetic resonance imaging contrast - Magnetic Resonance Electrical Impedance Tomography (MREIT) -sensitive to changes in active membrane conductivity. We compared standard deviations in MREIT phase data from spontaneously active Aplysia abdominal ganglia in an artificial seawater background solution (ASW) with those found after treatment with an excitotoxic solution (KCl). We found significant increases in MREIT treatment cases, compared to control ganglia subject to extra ASW. This distinction was not found in phase images from the same ganglia using no imaging current. Further, significance and effect size depended on the amplitude of MREIT imaging current used. We conclude that our observations were linked to changes in cell conductivity caused by activity. Functional MREIT may have promise as a more direct method of functional neuroimaging than existing methods that image correlates of blood flow such as BOLD fMRI.

Immune response to enzyme replacement therapies in lysosomal storage diseases and the role of immune tolerance induction

The US Food and Drug Administration (FDA) and National Organization for Rare Disease (NORD) convened a public workshop titled "Immune Responses to Enzyme Replacement Therapies: Role of Immune Tolerance Induction" to discuss the impact of anti-drug antibodies (ADAs) on efficacy and safety of enzyme replacement therapies (ERTs) intended to treat patients with lysosomal storage diseases (LSDs). Participants in the workshop included FDA staff, clinicians, scientists, patients, industry, and advocacy group representatives. The risks and benefits of implementing prophylactic immune tolerance induction (ITI) to reduce the potential clinical impact of antibody development were considered. Complications due to immune responses to ERT are being recognized with increasing experience and lengths of exposure to ERTs to treat several LSDs. Strategies to mitigate immune responses and to optimize therapies are needed. Discussions during the workshop resulted in the identification of knowledge gaps and future areas of research, as well as the following proposals from the participants: (1) systematic collection of longitudinal data on immunogenicity to better understand the impact of ADAs on long-term clinical outcomes; (2) development of disease-specific biomarkers and outcome measures to assess the effect of ADAs and ITI on efficacy and safety; (3) development of consistent approaches to ADA assays to allow comparisons of immunogenicity data across different products and disease groups, and to expedite reporting of results; (4) establishment of a system to widely share data on antibody titers following treatment with ERTs; (5) identification of components of the protein that are immunogenic so that triggers and components of the immune responses can be targeted in ITI; and (6) consideration of early ITI in patients who are at risk of developing clinically relevant ADA that have been demonstrated to worsen treatment outcomes.

Death, treatment decisions and the permanent vegetative state: evidence from families and experts

Some brain injured patients are left in a permanent vegetative state, i.e., they have irreversibly lost their capacity for consciousness but retained some autonomic physiological functions, such as breathing unaided. Having discussed the controversial nature of the permanent vegetative state as a diagnostic category, we turn to the question of the patients' ontological status. Are the permanently vegetative alive, dead, or in some other state? We present empirical data from interviews with relatives of patients, and with experts, to support the view that the ontological state of permanently vegetative patients is unclear: such patients are neither straightforwardly alive nor simply dead. Having defended this view from counter-arguments we turn to the practical question as to how these patients ought to be treated. Some relatives and experts believe it is right for patients to be shifted from their currently unclear ontological state to that of being straightforwardly dead, but many are concerned or even horrified by the only legally sanctioned method guaranteed to achieve this, namely withdrawal of clinically assisted nutrition and hydration. A way of addressing this distress would be to allow active euthanasia for these patients. This is highly controversial; but we argue that standard objections to allowing active euthanasia for this particular class of permanently vegetative patients are weakened by these patients' distinctive ontological status.

Evaluation of toxicities from combined metronomic and maximal-tolerated dose chemotherapy in dogs with osteosarcoma

OBJECTIVE

To evaluate the tolerability of a piroxicam and cyclophosphamide metronomic treatment protocol combined with carboplatin alone or carboplatin and doxorubicin at maximal-tolerated doses.

METHODS

Retrospective study of 30 dogs diagnosed with osteosarcoma. All dogs underwent amputation and chemotherapy treatment with one of the two maximal-tolerated dose protocols. Metronomic chemotherapy was administered in conjunction with these protocols, and continued subsequently. The protocols included 0 · 3 mg/kg piroxicam and 10 to 12 mg/M(2) cyclophosphamide with 300 mg/M(2) carboplatin alone, or 300 mg/M(2) carboplatin alternating with 30 mg/M(2) doxorubicin.

RESULTS

Fourteen dogs were treated with the carboplatin and metronomic protocol and 16 were treated with the carboplatin alternating with doxorubicin and metronomic protocol. Grades 3 and 4 toxicities overall were significantly (P = 0 · 018) more common in the former group. The disease-free interval of the carboplatin and metronomic group was 192 days, which was not significantly different (P = 0 · 916) to the 182 days for the carboplatin alternating with doxorubicin and metronomic group. The median survival times of the two groups were 217 and 189 days, respectively.

CLINICAL SIGNIFICANCE

Piroxicam and cyclophosphamide metronomic protocols can be safely administered in combination with maximal-tolerated dose chemotherapy protocols. A significantly higher frequency of toxicities was observed in dogs treated with the carboplatin and metronomic protocol.

Evidence-based guideline update: pharmacologic treatment for episodic migraine prevention in adults: report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Headache Society

OBJECTIVE

To provide updated evidence-based recommendations for the preventive treatment of migraine headache. The clinical question addressed was: What pharmacologic therapies are proven effective for migraine prevention?

METHODS

The authors analyzed published studies from June 1999 to May 2009 using a structured review process to classify the evidence relative to the efficacy of various medications available in the United States for migraine prevention.

RESULTS AND RECOMMENDATIONS

The author panel reviewed 284 abstracts, which ultimately yielded 29 Class I or Class II articles that are reviewed herein. Divalproex sodium, sodium valproate, topiramate, metoprolol, propranolol, and timolol are effective for migraine prevention and should be offered to patients with migraine to reduce migraine attack frequency and severity (Level A). Frovatriptan is effective for prevention of menstrual migraine (Level A). Lamotrigine is ineffective for migraine prevention (Level A).

Evidence-based guideline update: NSAIDs and other complementary treatments for episodic migraine prevention in adults: report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Headache Society

OBJECTIVE

To provide updated evidence-based recommendations for the preventive treatment of migraine headache. The clinical question addressed was: Are nonsteroidal anti-inflammatory drugs (NSAIDs) or other complementary treatments effective for migraine prevention?

METHODS

The authors analyzed published studies from June 1999 to May 2009 using a structured review process to classify the evidence relative to the efficacy of various medications for migraine prevention.

RESULTS

The author panel reviewed 284 abstracts, which ultimately yielded 49 Class I or Class II articles on migraine prevention; of these 49, 15 were classified as involving nontraditional therapies, NSAIDs, and other complementary therapies that are reviewed herein.

RECOMMENDATIONS

Petasites (butterbur) is effective for migraine prevention and should be offered to patients with migraine to reduce the frequency and severity of migraine attacks (Level A). Fenoprofen, ibuprofen, ketoprofen, naproxen, naproxen sodium, MIG-99 (feverfew), magnesium, riboflavin, and subcutaneous histamine are probably effective for migraine prevention (Level B). Treatments considered possibly effective are cyproheptadine, Co-Q10, estrogen, mefenamic acid, and flurbiprofen (Level C). Data are conflicting or inadequate to support or refute use of aspirin, indomethacin, omega-3, or hyperbaric oxygen for migraine prevention. Montelukast is established as probably ineffective for migraine prevention (Level B).

The ethics of attaching research conditions to access to new health technologies

Decisions on which new health technologies to provide are controversial because of the scarcity of healthcare resources, the competing demands of payers, providers and patients and the uncertainty of the evidence base. Given this, additional information about new health technologies is often considered valuable. One response is to make access to a new health technology conditional on further research. Access can be restricted to patients who participate in a research study, such as a randomised controlled trial; alternatively, a new treatment can be made generally available, but only on condition that further evidence is collected (eg, on long-term outcomes and adverse events, in patient registries). The National Institute for Health and Clinical Excellence (NICE), which provides guidance on which new health technologies to make available under the UK's NHS, for example, has made some research conditional recommendations, and the current interest in such options suggests that they are likely to become more prevalent in the future. This paper identifies and discusses the main ethical issues created by this distinctive range of recommendations. We argue that decisions to put research conditions on access to new technologies are compatible with widely accepted values, principles and practices relevant to resource allocation. However, there are important features of these distinctive judgements that must be taken into account by resource allocation decision-making bodies and research ethics committees, and that require new sorts of empirical data.

The virtue ethics approach to bioethics

This paper discusses the viability of a virtue-based approach to bioethics. Virtue ethics is clearly appropriate to addressing issues of professional character and conduct. But another major remit of bioethics is to evaluate the ethics of biomedical procedures in order to recommend regulatory policy. How appropriate is the virtue ethics approach to fulfilling this remit? The first part of this paper characterizes the methodology problem in bioethics in terms of diversity, and shows that virtue ethics does not simply restate this problem in its own terms. However, fatal objections to the way the virtue ethics approach is typically taken in bioethics literature are presented in the second section of the paper. In the third part, a virtue-based approach to bioethics that avoids the shortcomings of the typical one is introduced and shown to be prima facie plausible. The upshot is an inviting new direction for research into bioethics' methodology.

FMRI activation in language areas correlates with verb generation performance in children

Functional MRI mapping of language areas in children frequently employs a covert verb generation task. Because responses are not monitored, the relationship between fMRI activation and task performance is unknown. We compared fMRI activation during covert and overt verb generation to performance during the overt task. 15 children, ages 11-13 years, listened to concrete nouns and responded with related verbs covertly and overtly. A clustered fMRI acquisition allowed for recording of overt responses without motion artifacts. Region of interest analysis was also performed in areas that exhibited correlation between activation and performance during overt verb generation in left inferior frontal and left superior temporal gyri (along with their right hemisphere homologues). Regression analysis determined that during both covert and overt generation, left hemisphere regions showed positive correlations with average counts of verbs generated during the overt task. These results suggest that increased verb generation performance leads to increased activation. In addition, overt performance may be used as an estimator of covert performance.

Comparative disposition of [14C]ertapenem, a novel carbapenem antibiotic, in rat, monkey and man

1. The disposition and metabolism of ertapenem, a carbapenem antibiotic, was examined in rat, monkey and man. Sprague-Dawley rats and Rhesus monkeys were given, by intravenous administration, radiolabelled doses of ertapenem (60 and 30 mg kg(-1), respectively), and healthy normal volunteers received a single fixed dose of 1000 mg. Urine and faeces were collected for determination of total radioactivity. 2. In healthy volunteers, [14C]ertapenem was eliminated by a combination of hydrolytic metabolism to a beta-lactam ring-opened derivative and renal excretion of unchanged drug. Approximately equal amounts were excreted as a beta-lactam ring-opened metabolite and unchanged drug (36.7 and 37.5% of dose, respectively). A secondary amide hydrolysis product accounted for about 1% of the dose in man. About 10% of the administered radioactivity was recovered in faeces, which suggested that a minor fraction underwent biliary and/or intestinal excretion. 3. In animals, a greater fraction of the dose was eliminated via metabolism; excretion of unchanged drug accounted for 17 and 5% of dose in rats and monkeys, respectively. In monkeys, the beta-lactam ring-opened and amide hydrolysis metabolites accounted for 74.8 and 7.59% of the dose, respectively, whereas in rats, these metabolites accounted for 31.9 and 20% of dose, respectively. 4. In vitro studies with fresh rat tissue homogenates indicated that lung and kidney were the primary organs involved in mediating formation of the beta-lactam ring-opened metabolite. The specific inhibitor of dehydropeptidase-I, cilastatin, inhibited the in vivo and in vitro metabolism of ertapenem in rats, which suggested strongly that the hydrolysis of ertapenem in lung and kidney was mediated by this enzyme.

Effect of polymer molecular weight on the production of drug nanoparticles

Stable, polymer-coated nanoparticles of two hydrophobic drugs, namely nabumetone and halofantrine, have been prepared by a wet-bead milling process performed in the presence of a stabilizing homopolymer, either hydroxypropylmethylcellulose (HPMC) or polyvinylpyrrolidone (PVP), of differing molecular weights and concentrations. Although nabumetone nanoparticles could only be produced when HPMC was used as stabilizing polymer, halofantrine nanoparticles could be prepared using either HPMC or PVP. Stable nanoparticles of nabumetone could be produced using a HPMC solution of viscosity average molecular weight, M(v), of 5 kg/mol over an approximate four fold polymer concentration range (0.63-2.5% w/w) when a drug loading of 20% w/w was used. Increasing the molecular weight of HPMC up to a limiting M(v) of 89 kg/mol did not result in the formation of nanoparticles at any of the polymer concentrations examined. The amount of polymer absorbed onto the nanoparticles was determined by measuring the depletion of polymer from solution based on either an ultra-violet (PVP) or optical rotatory dispersion (ORD) (HPMC) assay. The slightly lower concentration of HMPC found to be present on the surface of the halofantrine nanoparticles compared with the nabumetone nanoparticles suggested a differing affinity of the polymer for the surface of the two drugs.

Measurements of atmospheric brightness temperature fluctuations and their implications on passive remote sensing

Passive remote sensing of airborne chemicals at infrared wavelengths may be limited by temporal fluctuations in atmospheric brightness temperatures deltaT(t). Brightness temperatures in two infrared spectral bands were simultaneously measured on clear and cloudy days along three lines of sights. For time windows t < 3-5 s, deltaT(t) remained constant at the sensor noise level and rapidly increased as t increased. The fluctuation time scale for the cloudy day was longer than for the clear day. The long correlation time for T(t) limits the utility of signal averaging in improving detection signal-to-noise ratio (SNR). The simultaneous outputs of the two spectral channels during the clear day exhibited no spectral coherence at t < 3 s and limited coherence at t > 30 s. Measurements during the cloudy day were largely coherent. Consequently, band-by-band subtraction may have limited benefits.

Peer networks, parental attributes, and drug use among Asian-Indian adolescents born in the United States

This study examined the interrelationships among peer networks, parental attributes, and drug use among Asian-Indian adolescents born in the United States whose parents emigrated from India. The sample consisted of 200 Asian-Indian adolescents, 116 males and 84 females, aged 13 to 18, who were born in the United States and resided in the greater New York metropolitan area. The subjects were interviewed using a semistructured instrument adapted from relevant validated scales and items from other researchers. Adolescent-reported data were analyzed using descriptive and univariable techniques. Of the 200 subjects, 32.5% had tried some form of tobacco, alcohol, or other drug, and 67.5% did not report drug use of any kind. The adolescents stated whether they had ever (at least one time) smoked cigarettes (16.5%), drank beer (18%), drank wine (20.5%), or smoked marijuana (2.5%). The parents' communication of the harmful consequences of drug use and approval of the adolescents' peer networks correlated (p < .05) independently with less drug use by the adolescents. The parents' concern for education was positively correlated (p < .05) with the adolescents' academic performance. The prevalence of drug use among Asian-Indian adolescents is low. Parents' awareness of their children's school performance, peer networks, and concerns related to the consequences of drug use can be used as an effective mechanism to communicate the prevention of drug use among adolescents.

Resonances in ferromagnetic gratings detected by microwave photoconductivity

We investigate the impact of microwave excited spin excitations on the dc charge transport in a ferromagnetic (FM) grating. We observe both resonant and nonresonant microwave photoresistance, which are caused, respectively, by spin and charge dissipations of the microwave power into the FM. A macroscopic model based on Maxwell and Landau-Lifschitz equations reveals the mixing of spin and charge dissipations, which shows that the ferromagnetic anti-resonance is shifted when the conductivity is anisotropic. We find that the microwave photoconductivity provides a powerful new tool to study the interplay between photonic, spintronic, and charge effects in FM microstructures.

Quantized dispersion of two-dimensional magnetoplasmons detected by photoconductivity spectroscopy

We find that the long-wavelength magnetoplasmon, resistively detected by photoconductivity spectroscopy in high-mobility two-dimensional electron systems, deviates from its well-known semiclassical nature as uncovered in conventional absorption experiments. A clear filling-factor dependent plateau-type dispersion is observed that reveals a so far unknown relation between the magnetoplasmon and the quantum Hall effect.

Bluetongue surveillance methods in the United States of America

Historical surveillance for bluetongue virus (BTV) exposure in the United States of America (USA) has relied on periodical serological surveillance using samples collected from cattle at slaughter. Most of this surveillance has been focused on the north-eastern portion of the USA due to the lack of competent vectors of BTV in this region. For most of the states tested in this region, the prevalence of seropositive animals has been less than 2%. Recently, a study was conducted in north-central USA using sentinel cattle herds. Results of serological testing showed an increasing gradient of exposure from north to south. In addition, detection of Culicoides sonorensis showed a similar gradient with detection in the northern areas being relatively rare. The results of these studies indicate that cattle herds in the northern and north-eastern areas of the USA are likely to be free of BTV.

Pharmacokinetics of total and unbound ertapenem in healthy elderly subjects

Ertapenem is a new once-a-day parenteral carbapenem antimicrobial agent. The pharmacokinetics of unbound and total concentrations of ertapenem in plasma were investigated in elderly subjects and compared with historical data from young adults. In a single- and multiple-dose study, healthy elderly males and females (n = 14) 65 years old or older were given a 1-g intravenous (i.v.) dose once daily for 7 days. Plasma and urine samples collected for 24 h on days 1 and 7 following administration of the 1-g doses were analyzed by reversed-phase high-performance liquid chromatography. Areas under the concentration-time curve from 0 h to infinity (AUC(0- infinity )) for elderly females and males were similar following administration of 1-g single i.v. doses, and thus, the genders were pooled in subsequent analyses. Concentrations in plasma and the half-life of ertapenem were generally higher and longer, respectively, in elderly subjects than in young adults. The mean AUC(0- infinity ) of total ertapenem in the elderly was 39% higher than that in young subjects following administration of a 1-g dose. The differences were slightly greater for the mean AUC(0- infinity ) of unbound ertapenem (71%). The unbound fraction of ertapenem in elderly subjects ( approximately 5 to 11%) was generally greater than that in young adults ( approximately 5 to 8%). As in young adults, ertapenem did not accumulate upon multiple dosing in the elderly. The pharmacokinetics of ertapenem in elderly subjects, while slightly different from those in young adults, do not require a dosage adjustment for elderly patients.

Pharmacokinetics of ertapenem in healthy young volunteers

Ertapenem (INVANZ) is a new once-a-day parenteral beta-lactam antimicrobial shown to be effective as a single agent for treatment of various community-acquired and mixed infections. The single- and multiple-dose pharmacokinetics of ertapenem at doses up to 3 g were examined in healthy young men and women volunteers. Plasma and urine samples collected were analyzed using reversed-phase high-performance liquid chromatography with UV detection. Ertapenem is highly bound to plasma protein. The protein binding changes from approximately 95% bound at concentrations of <50 micro g/ml to approximately 92% bound at concentrations of 150 micro g/ml (concentration at the end of a 30-min infusion following the 1-g dose). The nonlinear protein binding of ertapenem resulted in a slightly less than dose proportional increase in the area under the curve from 0 h to infinity (AUC(0- infinity )) of total ertapenem. The single-dose AUC(0- infinity ) of unbound ertapenem was nearly dose proportional over the dose range of 0.5 to 2 g. The mean concentration of ertapenem in plasma ranged from approximately 145 to 175 micro g/ml at the end of a 30-min infusion, from approximately 30 to 34 micro g/ml at 6 h, and from approximately 9 to 11 micro g/ml at 12 h. The mean plasma t(1/2) ranged from 3.8 to 4.4 h. About 45% of the plasma clearance (CL(P)) was via renal clearance. The remainder of the CL(P) was primarily via the formation of the beta-lactam ring-opened metabolite that was excreted in urine. There were no clinically significant differences between the pharmacokinetics of ertapenem in men and women. Ertapenem does not accumulate after multiple once-daily dosing.