What is the Philosophy of Neurosurgery? Systematic Review and Defining the Discipline.

INTRODUCTION: Despite centuries of joint investigation of philosophy and neurological interventions, a founding account for the philosophy of neurosurgery has yet to be rigorously constructed or defended. This paper reviews recent work on the philosophy of neurosurgery, spanning metaphysics, epistemology, and value theory, to establish a framework and clinical relevance for study in the philosophy of neurosurgery. METHODS: A systematic review of an online database was conducted using the broad search terms, "Philosophy AND (Neurosurgery OR Neurological Surgery)." Records were included if they demonstrated relevance to the philosophy of neurosurgery and analytical rigor, but were excluded if solely legal, clinical, or ethical principles were considered without substantive discussion of underlying ethical frameworks and philosophical principles. RESULTS: Of 8025 candidates from online and print records, 16 records (14 from online sources and 2 from an edited volume) met inclusion criteria for the systematic review. Three dealt with metaphysics, 3 dealt with epistemology, 4 dealt with value theory, 5 dealt with metaphysics/epistemology, and 1 dealt with value theory/metaphysics. Questions of free will, consciousness, personal identity, neurosurgical knowledge, ascription of other minds, deontology, and minimalism, among others, were considered. DISCUSSION: Based on identified studies, the philosophy of neurosurgery is defined as the discipline of rigorously and methodically addressing metaphysical, epistemological, and value-theoretic questions arising from physically intervening in the nervous system. We discuss future directions for questions within the philosophy of neurosurgery and consider their relevance for patient care and the practice of neurosurgery.

Comparative kinetics of humans and non-human primates during vertical climbing.

Climbing represents a critical behavior in the context of primate evolution. However, anatomically modern human populations are considered ill-suited for climbing. This adaptation can be attributed to the evolution of striding bipedalism, redirecting anatomical traits away from efficient climbing. Although prior studies have speculated on the kinetic consequences of this anatomical reorganization, there is a lack of data on the force profiles of human climbers. This study utilized high-speed videography and force plate analysis to assess single limb forces during climbing from 44 human participants of varying climbing experience and compared these data with climbing data from eight species of non-human primates (anthropoids and strepsirrhines). Contrary to expectations, experience level had no significant effect on the magnitude of single limb forces in humans. Experienced climbers did, however, demonstrate a predictable relationship between center of mass position and peak normal forces, suggesting a better ability to modulate forces during climbing. Humans exhibited significantly higher peak propulsive forces in the hindlimb compared with the forelimb and greater hindlimb dominance overall compared with non-human primates. All species sampled demonstrated exclusively tensile forelimbs and predominantly compressive hindlimbs. Strepsirrhines exhibited a pull-push transition in normal forces, while anthropoid primates, including humans, did not. Climbing force profiles are remarkably stereotyped across humans, reflecting the universal mechanical demands of this form of locomotion. Extreme functional differentiation between forelimbs and hindlimbs in humans may help to explain the evolution of bipedalism in ancestrally climbing hominoids.

Deep Brain Stimulation as an Emerging Therapy for Cognitive Decline in Alzheimer Disease: Systematic Review of Evidence and Current Targets.

OBJECTIVE: With no cure for Alzheimer disease (AD), current efforts involve therapeutics that prevent further cognitive impairment. Deep brain stimulation (DBS) has been studied for its potential to mitigate AD symptoms. This systematic review investigates the efficacy of current and previous targets for their ability to slow cognitive decline in treating AD. METHODS: A systematic review of the literature was performed through a search of the PubMed, Scopus, and Web of Science databases. Human studies between 1994 and 2023 were included. Sample size, cognitive outcomes, and complications were recorded for each study. RESULTS: Fourteen human studies were included: 7 studies with 6 distinct cohorts (n = 56) targeted the fornix, 6 studies with 3 distinct cohorts (n = 17) targeted the nucleus basalis of Meynert (NBM), and 1 study (n = 3) investigated DBS of the ventral striatum (VS). The Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental State Examination, and Clinical Dementia Rating Scale Sum of Boxes were used as the primary outcomes. In 5 of 6 cohorts where DBS targeted the fornix, cognitive decline was slowed based on the Alzheimer's Disease Assessment Scale-Cognitive Subscale or Mini-Mental State Examination scores. In 2 of 3 NBM cohorts, a similar reduction was reported. When DBS targeted the VS, the patients' Clinical Dementia Rating Scale Sum of Boxes scores indicated a slowed decline. CONCLUSIONS: This review summarizes current evidence and addresses variability in study designs regarding the therapeutic benefit of DBS of the fornix, NBM, and VS. Because of varying study parameters, varying outcome measures, varying study durations, and limited cohort sizes, definitive conclusions regarding the utility of DBS for AD cannot be made. Further investigation is needed to determine the safety and efficacy of DBS for AD.

Endoscopic Anterior Lumbar Interbody Fusion: Systematic Review and Meta-Analysis.

Laparoscopic anterior lumbar interbody fusion (L-ALIF), which employs laparoscopic cameras to facilitate a less invasive approach, originally gained traction during the 1990s but has subsequently fallen out of favor. As the envelope for endoscopic approaches continues to be pushed, a recurrence of interest in laparoscopic and/or endoscopic anterior approaches seems possible. Therefore, evaluating the current evidence base in regard to this approach is of much clinical relevance. To this end, a systematic literature search was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using the following keywords: "(laparoscopic OR endoscopic) AND (anterior AND lumbar)." Out of the 441 articles retrieved, 22 were selected for quantitative analysis. The primary outcome of interest was the radiographic fusion rate. The secondary outcome was the incidence of perioperative complications. Meta-analysis was performed using RStudio's "metafor" package. Of the 1,079 included patients (mean age, 41.8±2.9 years), 481 were males (44.6%). The most common indication for L-ALIF surgery was degenerative disk disease (reported by 18 studies, 81.8%). The mean follow-up duration was 18.8±11.2 months (range, 6-43 months). The pooled fusion rate was 78.9% (95% confidence interval [CI], 68.9-90.4). Complications occurred in 19.2% (95% CI, 13.4-27.4) of L-ALIF cases. Additionally, 7.2% (95% CI, 4.6-11.4) of patients required conversion from L-ALIF to open surgery. Although L-ALIF does not appear to be supported by studies available in the literature, it is important to consider the context from which these results have been obtained. Even if these results are taken at face value, the failure of endoscopy to have a role in the ALIF approach does not mean that it should not be incorporated in posterior approaches.

[Takotsubo cardiomyopathy associated with abnormal birth of the coronary arteries]. / Miocardiopatía de Takotsubo asociada al nacimiento anómalo de las arterias coronarias.

Background: Takotsubo cardiomyopathy (TM) is a form of non-ischemic cardiomyopathy. It is characterized by transient regional systolic dysfunction of the left ventricle that mimics acute myocardial infarction. The main objective of this article is to report the case of a patient with TM associated with abnormal birth of the left coronary trunk. Clinical case: A 76-year-old woman with typical angina at rest, with an electrocardiogram that showed dynamic changes in the T wave and elevation of biomarkers. Coronary angiography showed epicardial coronary arteries without significant lesions and abnormal birth of the left coronary trunk from the proximal segment of the right coronary artery. The patient progressed favorably, and the transthoracic echocardiogram showed no mobility disorders 3 months after the event. Conclusions: TM and abnormal birth of the coronary arteries are rare diseases whose simultaneous presentation is extraordinary. The diagnosis of both clinical entities is made by coronary angiography and echocardiogram, and their treatment is similar to that of patients with acute coronary syndrome. Abnormal birth of the left coronary trunk with retroaortic switch reaching the contralateral site has a good clinical prognosis and echocardiographic follow-up should be performed 4 weeks after the onset of the condition.

Introducción: la miocardiopatía de Takotsubo (MT) es una forma de miocardiopatía no isquémica. Se caracteriza por la disfunción sistólica regional transitoria del ventrículo izquierdo que imita al infarto agudo de miocardio. El objetivo principal de este artículo es reportar el caso de una paciente con MT asociada al nacimiento anómalo del tronco coronario izquierdo. Caso clínico: paciente mujer de 76 años que presentó angina típica en reposo, con un electrocardiograma que evidenció cambios dinámicos en la onda T y elevación de biomarcadores. La coronariografía evidenció a las arterias coronarias epicárdicas sin lesiones significativas y el nacimiento anómalo del tronco coronario izquierdo proveniente del segmento proximal de la arteria coronaria derecha. La paciente evolucionó de manera favorable y el ecocardiograma transtorácico no mostró trastornos en la movilidad a los tres meses del evento. Conclusiones: la MT y el nacimiento anómalo de las arterias coronarias son enfermedades raras cuya presentación simultánea es extraordinaria. El diagnóstico de ambas entidades clínicas se realiza mediante la coronariografía y el ecocardiograma, y su tratamiento es similar al de los pacientes con síndrome coronario agudo. El nacimiento anómalo del tronco coronario izquierdo con cruce retroaórtico que alcanza el sitio contralateral tiene un buen pronóstico y se debe realizar seguimiento clínico y ecocardiográfico a las cuatro semanas del inicio del padecimiento.

Structural brain differences in essential tremor and Parkinson's disease deep brain stimulation patients.

BACKGROUND: Essential tremor (ET) and Parkinson's disease (PD) are the most common tremor disorders and are common indications for deep brain stimulation (DBS). In some patients, PD and ET symptoms overlap and diagnosis can be challenging based on clinical criteria alone. The objective of this study was to identify structural brain differences between PD and ET DBS patients to help differentiate these disorders and improve our understanding of the different brain regions involved in these pathologic processes. METHODS: We included ET and PD patients scheduled to undergo DBS surgery in this observational study. Patients underwent 3T brain MRI while under general anesthesia as part of their procedure. Cortical thicknesses and subcortical volumes were quantified from T1-weighted images using automated multi-atlas segmentation. We used logistic regression analysis to identify brain regions associated with diagnosis of ET or PD. RESULTS: 149 ET and 265 PD patients were included. Smaller volumes in the pallidum and thalamus and reduced thickness in the anterior orbital gyrus, lateral orbital gyrus, and medial precentral gyrus were associated with greater odds of ET diagnosis. Conversely, reduced volumes in the caudate, amygdala, putamen, and basal forebrain, and reduced thickness in the orbital part of the inferior frontal gyrus, supramarginal gyrus, and posterior cingulate were associated with greater odds of PD diagnosis. CONCLUSIONS: These findings identify structural brain differences between PD and ET patients. These results expand our understanding of the different brain regions involved in these disorders and suggest that structural MRI may help to differentiate patients with these two disorders.

External Validation of the Global Alignment and Proportion Score as Prognostic Tool for Corrective Surgery in Adult Spinal Deformity: A Systematic Review and Meta-Analysis.

BACKGROUND: Since its proposal, the Global Alignment and Proportion (GAP) score has been the topic of several external validation studies, which have yielded conflicting results. Given the lack of consensus regarding this prognostic tool, the authors aim to assess the accuracy of GAP scores for predicting mechanical complications following adult spinal deformity correction surgery. METHODS: A systematic search was performed using PubMed, Embase, and Cochrane Library for the purpose of identifying all studies evaluating the GAP score as a predictive tool for mechanical complications. GAP scores were pooled using a random-effects model to compare patients reporting mechanical complications after surgery versus those reporting no complications. Where receiver operator curves were provided, the area under the curve (AUC) was pooled. RESULTS: A total of 15 studies featuring 2092 patients were selected for inclusion. Qualitative analysis using Newcastle-Ottawa criteria revealed moderate quality among all included studies (5.99/9). With respect to sex, the cohort was predominantly female (82%). The pooled mean age among all patients in the cohort was 58.55 years, with a mean follow-up of 33.86 months after surgery. Upon pooled analysis, we found that mechanical complications were associated with higher mean GAP scores, albeit minimal (mean difference = 0.571 [ 95% confidence interval: 0.163-0.979]; P = 0.006, n = 864). Additionally, age (P = 0.136, n = 202), fusion levels (P = 0.207, n = 358), and body mass index (P = 0.616, n = 350) were unassociated with mechanical complications. Pooled AUC revealed poor discrimination overall (AUC = 0.69; n = 1206). CONCLUSIONS: GAP scores may have a minimal-to-moderate predictive capability for mechanical complications associated with adult spinal deformity correction.

A deep catalog of protein-coding variation in 985,830 individuals.

Coding variants that have significant impact on function can provide insights into the biology of a gene but are typically rare in the population. Identifying and ascertaining the frequency of such rare variants requires very large sample sizes. Here, we present the largest catalog of human protein-coding variation to date, derived from exome sequencing of 985,830 individuals of diverse ancestry to serve as a rich resource for studying rare coding variants. Individuals of African, Admixed American, East Asian, Middle Eastern, and South Asian ancestry account for 20% of this Exome dataset. Our catalog of variants includes approximately 10.5 million missense (54% novel) and 1.1 million predicted loss-of-function (pLOF) variants (65% novel, 53% observed only once). We identified individuals with rare homozygous pLOF variants in 4,874 genes, and for 1,838 of these this work is the first to document at least one pLOF homozygote. Additional insights from the RGC-ME dataset include 1) improved estimates of selection against heterozygous loss-of-function and identification of 3,459 genes intolerant to loss-of-function, 83 of which were previously assessed as tolerant to loss-of-function and 1,241 that lack disease annotations; 2) identification of regions depleted of missense variation in 457 genes that are tolerant to loss-of-function; 3) functional interpretation for 10,708 variants of unknown or conflicting significance reported in ClinVar as cryptic splice sites using splicing score thresholds based on empirical variant deleteriousness scores derived from RGC-ME; and 4) an observation that approximately 3% of sequenced individuals carry a clinically actionable genetic variant in the ACMG SF 3.1 list of genes. We make this important resource of coding variation available to the public through a variant allele frequency browser. We anticipate that this report and the RGC-ME dataset will serve as a valuable reference for understanding rare coding variation and help advance precision medicine efforts.

Resident Training in Spine Surgery: A Systematic Review of Simulation-Based Educational Models.

OBJECTIVE: With the increasing prevalence of spine surgery, ensuring effective resident training is becoming of increasing importance. Training safe, competent surgeons relies heavily on effective teaching of surgical indications and adequate practice to achieve a minimum level of technical proficiency before independent practice. American Council of Graduate Medical Education work-hour restrictions have complicated the latter, forcing programs to identify novel methods of surgical resident training. Simulation-based training is one such method that can be used to complement traditional training. The present review aims to evaluate the educational success of simulation-based models in the spine surgical training of residents. METHODS: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the PubMed, Web of Science, and Google Scholar databases were systematically screened for English full-text studies examining simulation-based spine training curricula. Studies were categorized based on simulation model class, including animal-cadaveric, human-cadaveric, physical/3-dimensional, and computer-based/virtual reality. Outcomes studied included participant feedback regarding the simulator and competency metrics used to evaluate participant performance. RESULTS: Seventy-two studies were identified. Simulators displayed high face validity and were useful for spine surgery training. Objective measures used to evaluate procedural performance included implant placement evaluation, procedural time, and technical skill assessment, with numerous simulators demonstrating a learning effect. CONCLUSIONS: While simulation-based educational models are one potential means of training residents to perform spine surgery, traditional in-person operating room training remains pivotal. To establish the efficacy of simulators, future research should focus on improving study quality by leveraging longitudinal study designs and correlating simulation-based training with clinical outcome measures.

Schizophrenia and neurosurgery: systematic review and theories.

OBJECTIVE: Despite its relatively low prevalence, schizophrenia has a high burden of illness due to its lifelong effects and the fact that it is often refractory to psychotropic treatment. This review investigated how neurosurgical interventions, primarily neuromodulation through deep brain stimulation (DBS), can mitigate treatment-refractory schizophrenia. Pathophysiological data and ongoing clinical trials were reviewed to suggest which targets hold promise for neurosurgical efficacy. METHODS: A systematic review of the literature was conducted via an electronic search of the PubMed, Scopus, and Web of Science databases. Included papers were human or animal studies of neurosurgical interventions for schizophrenia conducted between 2012 and 2022. An electronic search of ClinicalTrials.gov and the International Clinical Trials Registry Platform was conducted to find ongoing clinical trials. The ROBINS-I (Risk of Bias in Nonrandomized Studies of Interventions) assessment tool was used to evaluate risk of bias in the study. RESULTS: Eight human and 2 rat studies were included in the review. Of the human studies, 5 used DBS targeting the nucleus accumbens, subgenual anterior cingulate cortex, habenula, and substantial nigra pars reticulata. The remaining 3 human studies reported the results of subcaudate tractotomies and anterior capsulotomies. The rat studies investigated DBS of the nucleus accumbens and medial prefrontal cortex. Overall, human studies demonstrated long-term reduction in Positive and Negative Syndrome Scale scores in many participants, with a low incidence of surgical and psychological side effects. The rat studies demonstrated improved prepulse and latent inhibition in the targeted areas after DBS. CONCLUSIONS: As identified in this review, recent studies have investigated the potential effects of therapeutic DBS for schizophrenia, with varying results. DBS targets that have been explored include the hippocampus, subgenual anterior cingulate cortex, habenula, substantia nigra pars reticulata, and medial prefrontal cortex. In addition to DBS, other neuromodulatory techniques such as neuroablation have been studied. Current evidence suggests that neuroablation in the subcaudate tract and anterior capsulotomy may be beneficial for some patients. The authors recommend further exploration of neuromodulation for treatment-refractory schizophrenia, under the condition that rigorous standards be upheld when considering surgical candidacy for these treatments, given that their safety and efficacy remain to be determined.

Metabolic impact of infant formulas in young infants. An outlook from the urine metabolome.

Introduction: Although breast milk is the ideal food source for newborns during the first six months of life, a high percentage of children receive infant formulas. There is evidence that specific diet habits may influence individual metabolic profile. Therefore, in newborns, such profile can be influenced by the use of infantile formulas given the composition differences that display compared to human milk. Up to now, there are no reports in the literature that address this issue. Objectives: this work aims to compare the metabolic profile of full-term newborns that were feed with either breast milk (n = 32) or infantile formulas (n = 21). Methods: Metabolic profile was established based on urine analysis through gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (H-NMR). Results: our results evidenced a more gluconeogenic profile in breast-fed infants characterized by elevation of Kreb's cycle intermediaries like fumaric, succinic and ketoglutaric acids compared to infants receiving infant formula. In addition, infant formula fed infants presented urinary excretion of metabolites derived from specific compounds present in this type of diet that were not observed in breast-fed infants, for instance D-glucitol, and 4-deoxytetronic. Moreover, in infant formula fed infants there was excretion of basal levels of metabolites of clinical relevance like 3-hydroxy-3-methyl-glutaric, 2-methyl-3-keto-valeric and 3,4-dihydroxybutyric. Conclusion: These results show the importance of understanding the metabolic impact of diet in newborn population in normal and pathological contexts.

A Chirality-Based Quantum Leap.

There is increasing interest in the study of chiral degrees of freedom occurring in matter and in electromagnetic fields. Opportunities in quantum sciences will likely exploit two main areas that are the focus of this Review: (1) recent observations of the chiral-induced spin selectivity (CISS) effect in chiral molecules and engineered nanomaterials and (2) rapidly evolving nanophotonic strategies designed to amplify chiral light-matter interactions. On the one hand, the CISS effect underpins the observation that charge transport through nanoscopic chiral structures favors a particular electronic spin orientation, resulting in large room-temperature spin polarizations. Observations of the CISS effect suggest opportunities for spin control and for the design and fabrication of room-temperature quantum devices from the bottom up, with atomic-scale precision and molecular modularity. On the other hand, chiral-optical effects that depend on both spin- and orbital-angular momentum of photons could offer key advantages in all-optical and quantum information technologies. In particular, amplification of these chiral light-matter interactions using rationally designed plasmonic and dielectric nanomaterials provide approaches to manipulate light intensity, polarization, and phase in confined nanoscale geometries. Any technology that relies on optimal charge transport, or optical control and readout, including quantum devices for logic, sensing, and storage, may benefit from chiral quantum properties. These properties can be theoretically and experimentally investigated from a quantum information perspective, which has not yet been fully developed. There are uncharted implications for the quantum sciences once chiral couplings can be engineered to control the storage, transduction, and manipulation of quantum information. This forward-looking Review provides a survey of the experimental and theoretical fundamentals of chiral-influenced quantum effects and presents a vision for their possible future roles in enabling room-temperature quantum technologies.

Emergence of Floquet edge states in the coupled Su-Schrieffer-Heeger model.

The emergence of non equilibrium topological phases in low dimensional systems offers an interesting route for material properties engineering. We analyze the dynamical modulation of two coupled one-dimensional chains, described by the Su-Schrieffer-Heeger model. We find that the interplay of driving interactions and interchain coupling leads to the emergence of non-equilibrium edge states with nontrivial topological properties. Using an effective Hamiltonian approach, we quantify the emergent topological phases via the winding number and show that oscillations in the mean pseudospin polarization arise as a consequence of the periodic modulation. The patterns of these pseudospin oscillations are different for the static trivial and topological phases offering a dynamical means to distinguish both physical configurations. The system also exhibits non integer values of the winding number, which have been recently reported experimentally in connection to spin textures.

The prevalence of Chlamydia psittaci in confiscated Psittacidae in Colombia.

Chlamydia psittaci is a highly zoonotic bacteria distributed worldwide; it is responsible for psittacosis, one of the most important infectious diseases affecting the Psittacidae, mostly parrots. This work was aimed at determining C. psittaci prevalence and genotype in 177 parrots confiscated in Colombia; cloacal swab (166) and faecal (177) samples were analysed from birds confiscated and housed in a Temporary Wildlife Reception Centre (Centro de Reception de Fauna Temporal). Conventional PCR was run on the samples for amplifying the MOMP gene and then the ompA gene. The C. psittaci genotype A was found in 81.3 % (144/177) of the birds analysed. Cloacal swabs accounted for 129/166 (77.7 %) positive samples and faecal matter for 53/177 (29.9 %), 38 birds proving positive for both types of sample; there was an 8.15 times greater probability of detection for cloacal swabs compared to faecal swabs (p < 0.05). Clinical examination findings were correlated with the animals' positivity for cloacal swabs, faecal matter or both, finding a statistically significant relationship with low respiratory rate (p < 0.05) and broken plumage for cloacal swab sample results (p < 0.1). Even though 85 % seroprevalence has previously been reported in Colombia using indirect ELISA, this study reports for the first time C. psittaci genotype A endemicity in psittacines in captivity in Colombia using molecular techniques, considering the zoonotic risk involved in having these birds as pets.

UGT1A1 genetic variants are associated with increases in bilirubin levels in rheumatoid arthritis patients treated with sarilumab.

Sarilumab is a human monoclonal antibody against interleukin (IL)-6Rα that has been approved for the treatment of adult patients with moderately to severely active rheumatoid arthritis (RA) and an inadequate response or intolerance to one or more disease-modifying antirheumatic drugs (DMARDs). Mild liver function test abnormalities have been observed in patients treated with sarilumab. We describe a genome-wide association study of bilirubin elevations in RA patients treated with sarilumab. Array genotyping and exome sequencing were performed on DNA samples from 1075 patients. Variants in the UGT1A1 gene were strongly associated with maximum bilirubin elevations in sarilumab-treated patients (rs4148325; p = 2.88 × 10-41) but were not associated with aminotransferase elevations. No other independent loci showed evidence of association with bilirubin elevations after sarilumab treatment. These findings suggest that most bilirubin increases during sarilumab treatment are related to genetic variation in UGT1A1 rather than underlying liver injury.

Engineering a heterologously expressed fructosyltransferase from Aspergillus oryzae N74 in Komagataella phaffii (Pichia pastoris) for kestose production.

Fructo-oligosaccharides (FOS) are one of the most well-studied and commercialized prebiotics. FOS can be obtained either by controlled hydrolysis of inulin or by sucrose transfructosylation. FOS produced from sucrose are typically classified as short-chain FOS (scFOS), of which the best known are 1-kestotriose (GF2), 1,1-kestotetraose (GF3), and 1,1,1-kestopentaose (GF4), produced by fructosyltransferases (FTases) or ß-fructofuranosidases. In previous work, FOS production was studied using the Aspergillus oryzae N74 strain, its ftase gene was heterologously expressed in Komagataella phaffii (Pichia pastoris), and the enzyme's tertiary structure modeled. More recently, residues that may be involved in protein-substrate interactions were predicted. In this study, the aim was to experimentally validate previous in silico results by independently producing recombinant wild-type A. oryzae N74 FTase and three single-point mutations in Komagataella phaffii (Pichia pastoris). The R163A mutation virtually abolished the transfructosylating activity, indicating a requirement for the positively charged arginine residue in the catalytic domain D. In contrast, transfructosylating activity was improved by introducing the mutations V242E or F254H, with V242E resulting in higher production of GF2 without affecting that of GF3. Interestingly, initial sucrose concentration, reaction temperature and the presence of metal cofactors did not affect the enhanced activity of mutant V242E. Overall, these results shed light on the mechanism of transfructosylation of the FTase from A. oryzae and expand considerations regarding the design of biotechnological processes for specific FOS production.

Radiation modulated spin coupling in a double-stranded DNA model.

The spin activity in macromolecules such as DNA and oligopeptides, in the context of the chiral induced spin selectivity has been proposed to be due to the atomic spin-orbit coupling (SOC) and the associated chiral symmetry of the structures. This coupling, associated with carbon, nitrogen and oxygen atoms in biological molecules, albeit small (meV), can be enhanced by the geometry, and strong local polarization effects such as hydrogen bonding. A novel way to manipulate the spin degree of freedom is by modifying the spectrum using a coupling to the appropriate electromagnetic radiation field. Here we use the Floquet formalism in order to show how the half filled band Hamiltonian for DNA, can be modulated by the radiation to produce up to a tenfold increase of the effective SOC once the intrinsic coupling is present. On the other hand, the chiral model, once incorporating the orbital angular momentum of electron motion on the helix, opens a gap for different helicity states (helicity splitting) that chooses spin polarization according to transport direction and chirality, without breaking time reversal symmetry. The observed effects are feasible in physically reasonable parameter ranges for the radiation field amplitude and frequency.

Assessment of Adaptive Performance and its Role as a Moderator of the Relationship Between Person-Organization Fit and Organizational Citizenship Behaviors.

BACKGROUND: Adaptive performance is of central interest for today's organizations, insofar as employees increasingly need to be able to adjust their behaviors to dynamic, changing work situations. The aims of this study were to develop a Spanish adaptation of Charbonnier-Voirin and Roussel's (2012) scale for measuring adaptive performance, and to examine whether the dimensions of adaptive performance moderate the relationship between person-organization fit (PO fit) and organizational citizenship behaviors (OCBs). We hypothesized that the relationship between PO fit and OCBs would be stronger in individuals with a higher level of adaptive performance. METHOD: The sample comprised 678 employees (65% women) in the public sector in the Basque Country. They ranged from 21 to 63 years old (M = 44.63; SD = 7.66). RESULTS: The Spanish version of the scale has good psychometric properties. Furthermore, the Interpersonal Adaptability dimension of adaptive performance moderates the relationship between PO fit and OCBs directed both at the organization and at individuals, following the expected direction. The relationship between PO fit and OCBs directed at individuals was also moderated by the Reactivity in the Face of Emergencies dimension. CONCLUSIONS: We discuss the practical implications of these results in the field of personnel selection.

Assessment of Adaptive Performance and its Role as a Moderator of the Relationship Between Person - Organization Fit and Organizational Citizenship Behaviors / Evaluación del Desempeño Adaptativo y su Rol Moderador en la Relación Entre el Ajuste Persona - Organización y la Ciudadanía Organizacional

Background: Adaptive performance is of central interest for today’sorganizations, insofar as employees increasingly need to be able to adjusttheir behaviors to dynamic, changing work situations. The aims of thisstudy were to develop a Spanish adaptation of Charbonnier-Voirin andRoussel’s (2012) scale for measuring adaptive performance, and to examinewhether the dimensions of adaptive performance moderate the relationshipbetween person-organization fit (PO fit) and organizational citizenshipbehaviors (OCBs). We hypothesized that the relationship between POfit and OCBs would be stronger in individuals with a higher level ofadaptive performance. Method: The sample comprised 678 employees(65% women) in the public sector in the Basque Country. They rangedfrom 21 to 63 years old (M = 44.63; SD = 7.66). Results: The Spanishversion of the scale has good psychometric properties. Furthermore, theInterpersonal Adaptability dimension of adaptive performance moderatesthe relationship between PO fit and OCBs directed both at the organizationand at individuals, following the expected direction. The relationshipbetween PO fit and OCBs directed at individuals was also moderated bythe Reactivity in the Face of Emergencies dimension. Conclusions: Wediscuss the practical implications of these results in the field of personnelselection

Antecedentes: el desempeño adaptativo es una variable crucial enlas organizaciones actuales dado que la flexibilidad y la capacidad deadaptación son necesarias en un entorno laboral tan dinámico y cambiantecomo el actual. Los objetivos de este estudio fueron adaptar al castellanoel instrumento de Charbonnier-Voirin y Roussel (2012), que mide eldesempeño adaptativo y examinar si las dimensiones que configuranel desempeño adaptativo moderan la relación entre el ajuste persona-organización (PO fit) y las conductas de ciudadanía organizacional(OCBs). Se pronosticó que la relación entre PO fit y OCBs sería másintensa en aquellas personas con mayor desempeño adaptativo. Método: la muestra estuvo compuesta por 678 empleados/as (65% mujeres) delsector público del País Vasco, con edades comprendidas entre 21 y 63años (M = 44.63; SD = 7.66). Resultados: los resultados muestran quela versión española de la escala posee buenas propiedades psicométricas.Además, la dimensión Adaptabilidad Interpersonal del desempeñoadaptativo modera la relación entre el PO fit y las OCBs. En la predicciónde las OCBs dirigidas a otros individuos, la Reactividad ante emergenciastambién modera la relación. Conclusiones: se discuten las implicacionesprácticas que pueden tener en el ámbito de la selección de personal losresultados derivados del estudio.

Social Determinants of Transactional Sex in a Sample of Young Black and Latinx Sexual Minority Cisgender Men and Transgender Women.

PURPOSE: We sought to explore characteristics and risk factors associated with transactional sex in a sample of young black and Latinx sexual minority cisgender men and transgender women of age 15 to 24 years who were living with or at high risk for HIV infection and whether these associations vary by gender identity and HIV status. METHODS: A total of 454 black and Latinx sexual minority cisgender men and transgender women from Baltimore, MD; Philadelphia, PA; Washington, DC; and St. Petersburg/Tampa, Fl, were recruited to participate in a multisite study that included a 45-minute baseline Web-based survey and HIV-1 rapid testing. Bivariate analysis was used to explore factors associated with transactional sex. Factors significant at p-value <.20 in bivariate analysis were entered into a final logistic regression models; and models were further stratified by gender identity and HIV status. RESULTS: The mean age was 21.3 (standard deviation = 2.5), with 14.7% (n = 65) identifying as transgender, and 103 youth (22.7%) reporting lifetime transactional sex. Transactional sex was associated with transgender identity, recent unstable housing in the last 12 months, poorer perceived financial well-being, coerced sex, and marijuana use. Differences were noted by gender identity and HIV status, with marijuana use associated with transactional sex in cisgender men and unstable housing and sexual coercion in youth living with HIV. CONCLUSIONS: Young black and Latinx cisgender men and transgender women are at a high risk for engaging in transactional sex. Transactional sex may create a syndemic for HIV risk exposure through co-occurring and reinforcing conditions of unstable housing, violence, and substance use.