Compact 2D nonlinear photonic crystal source of beamlike path entangled photons.

We demonstrate a method to generate entangled photons with controlled spatial shape by parametric down conversion (PDC) in a 2D nonlinear crystal. A compact and novel crystal source was designed and fabricated, generating directly path entangled photons without the use of additional beam-splitters. This crystal supports two PDC processes, emitting biphotons into two beamlike modes simultaneously. Two coherent path entangled amplitudes of biphotons were created and their interference observed. Our method enables the generation of entangled photons with controlled spatial, spectral and polarization properties.

Entanglement swapping between photons that have never coexisted.

The role of the timing and order of quantum measurements is not just a fundamental question of quantum mechanics, but also a puzzling one. Any part of a quantum system that has finished evolving can be measured immediately or saved for later, without affecting the final results, regardless of the continued evolution of the rest of the system. In addition, the nonlocality of quantum mechanics, as manifested by entanglement, does not apply only to particles with spacelike separation, but also to particles with timelike separation. In order to demonstrate these principles, we generated and fully characterized an entangled pair of photons that have never coexisted. Using entanglement swapping between two temporally separated photon pairs, we entangle one photon from the first pair with another photon from the second pair. The first photon was detected even before the other was created. The observed two-photon state demonstrates that entanglement can be shared between timelike separated quantum systems.

HostSeq: a Canadian whole genome sequencing and clinical data resource.

HostSeq was launched in April 2020 as a national initiative to integrate whole genome sequencing data from 10,000 Canadians infected with SARS-CoV-2 with clinical information related to their disease experience. The mandate of HostSeq is to support the Canadian and international research communities in their efforts to understand the risk factors for disease and associated health outcomes and support the development of interventions such as vaccines and therapeutics. HostSeq is a collaboration among 13 independent epidemiological studies of SARS-CoV-2 across five provinces in Canada. Aggregated data collected by HostSeq are made available to the public through two data portals: a phenotype portal showing summaries of major variables and their distributions, and a variant search portal enabling queries in a genomic region. Individual-level data is available to the global research community for health research through a Data Access Agreement and Data Access Compliance Office approval. Here we provide an overview of the collective project design along with summary level information for HostSeq. We highlight several statistical considerations for researchers using the HostSeq platform regarding data aggregation, sampling mechanism, covariate adjustment, and X chromosome analysis. In addition to serving as a rich data source, the diversity of study designs, sample sizes, and research objectives among the participating studies provides unique opportunities for the research community.

Resource efficient source of multiphoton polarization entanglement.

Current photon entangling schemes require resources that grow with the photon number. We present a new approach that generates quantum entanglement between many photons, using only a single source of entangled photon pairs. The different spatial modes, one for each photon as required by other schemes, are replaced by different time slots of only two spatial modes. States of any number of photons are generated with the same setup, solving the scalability problem caused by the previous need for extra resources. Consequently, entangled photon states of larger numbers than before are practically realizable.

The biaxial nonlinear crystal BiB3O6 as a polarization entangled photon source using non-collinear type-II parametric down-conversion.

We describe the full characterization of the biaxial nonlinear crystal BiB3O6 (BiBO) as a polarization entangled photon source using non-collinear type-II parametric down-conversion. We consider the relevant parameters for crystal design, such as cutting angles, polarization of the photons, effective nonlinearity, spatial and temporal walk-offs, crystal thickness and the effect of the pump laser bandwidth. Experimental results showing entanglement generation with high rates and a comparison to the well investigated ß-BaB2O4 (BBO) crystal are presented as well. Changing the down-conversion crystal of a polarization entangled photon source from BBO to BiBO enhances the generation rate as if the pump power was increased by 2.5 times. Such an improvement is currently required for the generation of multiphoton entangled states.

Projection of two biphoton qutrits onto a maximally entangled state.

Bell state measurements, in which two quantum bits are projected onto a maximally entangled state, are an essential component of quantum information science. We propose and experimentally demonstrate the projection of two quantum systems with three states (qutrits) onto a generalized maximally entangled state. Each qutrit is represented by the polarization of a pair of indistinguishable photons-a biphoton. The projection is a joint measurement on both biphotons using standard linear optics elements. This demonstration enables the realization of quantum information protocols with qutrits, such as teleportation and entanglement swapping.

En bloc resection for malignant colouterine fistula.

Colouterine fistula is a rare clinical entity. A literature search revealed only a few reports dealing with this complex problem, mostly resulting as a complication of diverticular disease of the colon. During a 4-month period, we diagnosed and successfully treated 2 women with a malignant colouterine fistula originating from a primary colorectal carcinoma invading the uterus. We herein report on our experience dealing with this kind of pathology, with special emphasis on the surgical technique used to resect the tumoral mass "en bloc".

Mifepristone (RU486), a pure antiprogesterone drug, in combination with vinblastine for the treatment of progesterone receptor-positive desmoid tumor.

We report the case of a patient who developed a desmoid tumor following total proctocolectomy and J-pouch reconstruction that was unresponsive to any medical treatment. Based on estrogen receptor alpha (ERalpha) and progesterone receptor (PR) evaluation (ERalpha-negative, but PR-positive), treatment with mifepristone, a pure antiprogesterone drug, was initiated, and partial tumor regression was achieved.

Peanuts: gibberellin antagonists and genetically controlled differences in growth habit.

Treatment of peanuts with gibberellin changed the orientation of lateral branches of runners to that of erect ones, and two growth retardants changed those of the erect type to a more horizontal orientation. Little or no difference was found in amounts of endogenous gibberellin in the two types of plants, but amount of native gibberellic acid antagonists was higher in runner plants. Furthermore, runner plants contained a particular gibberellic acid inhibitor not found in erect plants. Applications of various auxins, antiauxins, and a cytokinin had no effect on tropistic growth of the side branches.

The possible association between IVF and breast cancer incidence.

BACKGROUND: The possible association between ovulation-inducing drugs and breast cancer development has been debated. Our aim was to evaluate the incidence of breast cancer in a cohort of women exposed to in vitro fertilization (IVF). METHODS: A retrospective cohort analysis was performed by linkage of the computerized database of all women treated at the IVF Unit at Assaf Harofeh Medical Center between 1986 and 2003, and the Israeli National Cancer Registry. The standardized incidence ratio (SIR) was computed as the ratio between the observed number of breast cancer cases and the expected cases, adjusted for age and continent of birth, in the general population. Tumor characteristics of the IVF patients were studied by reviewing original medical records. RESULTS: 35 breast carcinomas were diagnosed among 3,375 IVF-treated women, compared to 24.8 cases expected (SIR = 1.4; 95% CI 0.98-1.96). Age >or=40 years at IVF treatment (SIR = 1.9; 95% CI 0.97-3.30), hormonal infertility (SIR = 3.1; 95% CI 0.99-7.22), and >or=4 IVF cycles (SIR = 2.0; 95% CI 1.15-3.27) were found to be risk factors to develop breast cancer compared to the general population. Multivariate analysis revealed that women who underwent >or=4 IVF cycles compared to those with one to three cycles were at risk to develop breast cancer, although not significantly (SIR = 1.9; 95% CI 0.95-3.81). Of IVF-treated women 85% had ER(+) tumors and 29% had positive family history. CONCLUSIONS: A possible association between IVF therapy and breast cancer development was demonstrated, especially in women >or=40 years of age. These preliminary findings need to be replicated in other cohort studies.

Breast cancer in the elderly: histological, hormonal and surgical characteristics.

The characteristics, menstrual risk factors and surgical therapy of 187 consecutive patients more than 70 years of age (mean: 75.9) were investigated and compared with those of 609 patients less than 70 years of age (mean: 53.9). There was no difference in stage, size, state of axillary nodes, grade, histological types, Ki-67, vascular invasion, estrogen receptor rate, and HER-2/neu (+) rate. Positive progesterone receptor rate was higher in older patients (54.7% vs. 63.1%). Tumors were larger (p=0.01) and their stage higher (p=0.014) in patients more than 80 years of age. All menstrual risk factors were similar in the two groups. Positive familial history was more frequent in patients <60 years. Significantly more young patients used hormone replacement therapy (HRT) (21.8 vs. 8.6%). Older patients underwent less breast-conserving surgery (36.1 vs. 55.1%), and less axillary lymph node dissection (ALND) (69.7 vs. 84.9%). We conclude that breast cancer characteristics and menstrual risk factors are similar in the two age groups.

Isolation and Characterization of a Chromoplast-Specific Carotenoid-Associated Protein from Cucumis sativus Corollas.

The differentiation of chloroplasts to chromoplasts in corollas of cucumber (Cucumis sativus) is subject to developmental control. To study factors involved in the chloroplast-chromoplast conversion, a chromoplast-specific protein of 35 kD was isolated, and polyclonal antibodies were prepared against it. This protein was found to be a principal component of the carotenoid-protein complex resolved from chromoplast membranes by nondenaturing gel electrophoresis. Immunological studies revealed that expression of this protein is regulated in a temporal and tissue-specific manner. Its steady-state level increased in parallel with flower development and carotenoid accumulation, peaking in mature flowers and then rapidly decreasing to very low levels. The protein was not detectable in cucumber leaves or fruits. To ascertain whether an organ-specific system regulates the chloroplast-chromoplast conversion and to enable future molecular studies of factors involved in this regulation, an in vitro bud culture system was established. Patterns of expression of the 35-kD protein and carotenoids in corollas of detached buds were similar to those in intact buds.

Chromoplast Biogenesis in Cucumis sativus Corollas (Rapid Effect of Gibberellin A3 on the Accumulation of a Chromoplast-Specific Carotenoid-Associated Protein).

The development of cucumber (Cucumis sativus L.) corollas is accompanied by the accumulation of chromoplasts. In mature corollas, chromoplasts, but no chloroplasts, were detected by electron microscopy. Chlorophyll was also undetectable in corollas at anthesis. The contents of carotenoids and a carotenoid-associated, chromoplast-specific, 35-kD protein in corollas increased in parallel with flower development, peaking concomitantly at anthesis. The involvement of phytohormones and light in the regulation of their expression was studied. When gibberellin A3 (GA3) was added to an in vitro bud culture system, accumulation of both carotenoids and the 35-kD protein was markedly enhanced. The specific up-regulation of the 35-kD protein was very rapid: after only 2 h of culture, increased levels were detected in GA3-treated versus untreated corollas. During this period, corolla fresh weight and total protein and carotenoid contents remained unchanged. Inclusion of abscisic acid in the culture medium counteracted the effect of GA3. Accumulation of the 35-kD protein was also enhanced when flower buds on plants were sprayed with GA3 or etiolated.

The low frequency of futility in an adult intensive care unit setting.

BACKGROUND: It is widely assumed that "futile" treatment consumes significant health care resources. This is a prospective cohort study. SETTING: The setting was the medical intensive care unit of Ben Taub General Hospital, a large public hospital in Houston, Tex. OBJECTIVE: To assess the frequency of intensive care unit patients meeting any of three broad definitions of futility. SUBJECTS: Subjects consisted of 129 consecutive patients admitted to the study intensive care unit during a 6-week period in the fall of 1993. MAIN OUTCOME MEASURES: Operational definitions for three types of futility described in the literature were developed: Imminent demise futility, death imminent regardless of intervention, was assessed by using the APACHE II (Acute Physiology and Chronic Health Evaluation II) scoring system to determine the likelihood of mortality at more than the 90%, 95%, and 99% probabilities. Lethal condition futility, conditions incompatible with long-term survival, included five separate disease processes. Qualitative futility, conditions with an unacceptable quality of life, was assessed as a persistent vegetative state or as meeting criteria for poor prognosis due to a hypoxic ischemic coma. RESULTS: Only 2 bed-days (0.3%) were used by patients with more than 90% predicted mortality; 22 bed-days (3.6%) were used by patients with poor prognosis due to hypoxic ischemic coma; and 101 bed-days (16.4%) were used by patients satisfying criteria for the five lethal conditions. CONCLUSIONS: The frequency of futile interventions appears to be low unless one is willing to accept a definition that includes patients who could survive for many months. If confirmed in other settings, this suggests that concepts of futility will not play a major role in costs containment.

Is cost a barrier to screening mammography for low-income women receiving Medicare benefits? A randomized trial.

BACKGROUND: In 1991, Medicare began covering screening mammograms subject to copayment and deductible. This study evaluated the effectiveness of Medicare in removing financial barriers to screening mammography among low-income older women. METHODS: In an inner-city public hospital's General Medicine Clinic, 119 consecutive, eligible, and consenting Medicare-enrolled women without known risk factors for breast cancer other than age, and no mammogram in the previous 2 years, were entered into a randomized controlled trial with follow-up after 2 months. The mean age was 71 years; 77% were black, 92% had an annual income below $10,000, and 52% had had a previous mammogram. All patients were counseled concerning indications for screening mammograms and Medicare coverage, and all were referred to a low-cost mammography facility. Sixty-one subjects were randomly assigned a voucher for a free screening mammogram at the referral facility. Obtaining a mammogram within 60 days of study entry was the main outcome measure. RESULTS: Of the women given vouchers, 27 (44%) obtained screening mammograms, compared with six (10%) of those without vouchers (P < .001). Adjustment by multiple logistic regression confirmed this association, yielding an adjusted odds ratio of 7.4 (95% confidence interval, 2.5 to 21.4). Knowledge concerning mammography and breast cancer increased significantly overall (and within randomization groups) between initial interview and follow-up; fear did not change. For women without the voucher, the main reason for not obtaining a mammogram was financial; the main reason for women with the voucher was transportation. CONCLUSION: In a low-income, inner-city population of older women, financial barriers to screening mammography persist despite Medicare coverage.

Entanglement dynamics in the presence of controlled unital noise.

Quantum entanglement is notorious for being a very fragile resource. Significant efforts have been put into the study of entanglement degradation in the presence of a realistic noisy environment. Here, we present a theoretical and an experimental study of the decoherence properties of entangled pairs of qubits. The entanglement dynamics of maximally entangled qubit pairs is shown to be related in a simple way to the noise representation in the Bloch sphere picture. We derive the entanglement level in the case when both qubits of a Bell state are transmitted through any arbitrary unital Pauli channel, and compare it to the case when the channel is applied only to one of the qubits. The dynamics of both cases was verified experimentally using an all-optical setup. We further investigated the evolution of partially entangled initial states. Different dynamics was observed for initial mixed and pure states of the same entanglement level.

Acquired immunodeficiency syndrome and the Americans with Disabilities Act: a legal duty to treat.

The emergence of the human immunodeficiency virus (HIV) as a serious public health threat has rekindled long dormant debate about individual physicians' duty to treat potentially contagious patients. Because of the widely accepted common-law tenet of the "no duty [to treat] rule," previous work on a duty to treat focused on historical reviews, medical society position statements, and the ethical arguments upon which the statements are based. The passage of the Americans with Disabilities Act has rendered these discussions moot by creating, through federal civil rights mechanisms, a legal duty to treat patients with HIV, enforceable under considerable penalties. The paper also concludes that there has been inadequate attention paid to similar civil rights concerns of infected physicians.

A novel polymorphism in intron 6 of the human p53 gene: a possible association with cancer predisposition and susceptibility.

We present a novel polymorphic 8-bp sequence in intron 6 of the p53 gene that maps between bp 55 and 62 of the 3' end of exon 6. Of normal blood samples, 32% were heterozygotic for this polymorphism and display a NN' genotype, whereas 68% of the population is homozygotic for the N genotype. The rare homozygotic genotype N' was detected only in four blood samples of cancer patients. Peripheral blood of gastrointestinal (GI) and breast tumor patients demonstrated a higher incidence of heterozygosity (50%) than that of normal individuals. Analysis of the distribution of this polymorphism in tumor samples showed loss of heterozygosity (LOH). This LOH during tumor progression could exhibit preference to each one of the polymorphic alleles. The rare presentation of one allele and the increased incidence of heterozygosity in carcinoma patients may suggest an association between this polymorphism with cancer predisposition and susceptibility. The fact that genetic alterations occurring in noncoding regions may play a role in tumor development only further increases the extent of involvement of p53 in carcinogenesis.

Thrombosis of superior vena cava during total parenteral nutrition, managed successfully with low dose streptokinase.

Superior vena cava syndrome due to catheter related thrombosis, developed in a patient receiving total parenteral nutrition. Local infusion of low dose streptokinase immediately proximal to the thrombus, was strikingly successful and may be the treatment of choice for this condition.

AIDS, surgery, and the Americans With Disabilities Act.

The acquired immunodeficiency syndrome and human immunodeficiency virus have had a major impact on the practice of medicine in the past 2 decades. Medical professionals are once again faced with a lethal contagious disease that has been transmitted in the health care setting to both patients and providers. Because of the stigma and fear associated with the infection, civil rights legislation, such as the Americans With Disabilities Act, has been used to protect infected individuals from inappropriate discrimination based on unwarranted fears and public hysteria. Various courts, with the backing of organized medicine and the public health authorities, have made it clear that it is illegal for a physician to refuse to treat a patient based on the patient's seropositivity. Unfortunately, various courts, with the backing of the American Medical Association and the Centers for Disease Control and Prevention, have made it clear that infected physicians are not necessarily afforded equal protection under the civil rights statutes.