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Animals use diverse solutions to land on vertical surfaces. Here we show the unique landing of the gliding gecko, Hemidactylus platyurus. Our high-speed video footage in the Southeast Asian rainforest capturing the first recorded, subcritical, short-range glides revealed that geckos did not markedly decrease velocity prior to impact. Unlike specialized gliders, geckos crashed head-first with the tree trunk at 6.0 ± 0.9 m/s (~140 body lengths per second) followed by an enormous pitchback of their head and torso 103 ± 34° away from the tree trunk anchored by only their hind limbs and tail. A dynamic mathematical model pointed to the utility of tails for the fall arresting response (FAR) upon landing. We tested predictions by measuring foot forces during landing of a soft, robotic physical model with an active tail reflex triggered by forefoot contact. As in wild animals, greater landing success was found for tailed robots. Experiments showed that longer tails with an active tail reflex resulted in the lower adhesive foot forces necessary for stabilizing successful landings, with a tail shortened to 25% requiring over twice the adhesive foot force., Siddall, Byrnes, Full, and Jusufi observe the function of the Asian flat-tailed gecko tail in gliding and landing on tree trunks in the field, complemented with mathematical and robotic models made of soft active materials. Altogether, their models show how geckos use an active tail reflex to brace the impact and reduce the risk of falling from landings on tree trunks.

Scientists whose first language is not English need to speak and write it constantly to gain fluency and become comfortable, says Lia Paola Zambetti. Scientists whose first language is not English need to speak and write it constantly to gain fluency and become comfortable, says Lia Paola Zambetti.

Anticipatory eye movement promotes cranio-caudal sequencing during walking turns. Clinical groups, such as Parkinson's disease (PD), do not produce anticipatory eye movements, leading to increased risk of falls. Visual cues may promote anticipatory eye movement by guiding the eyes into the turn. This study examined if visual cues could train anticipatory eye movement. Ten neurotypical young adults and 6 adults with PD completed three blocks of walking trials. Trials were blocked by visual condition: non-cued baseline turns (5 trials), visually cued turns (10 trials), and non-cued post turns (5 trials). A Delsys Trigno (Delsys, Boston, MA) recorded horizontal saccades at 1024 Hz via electrooculography (EOG). Two Optotrak cameras (Northern Digital Inc., ON, Canada) captured body segment kinematics at 120 Hz. Initiation of segment rotation with respect to ipsilateral foot contact (IFC1) prior to the turn was calculated. Neurotypical young adults (NYA) produced typical cranio-caudal rotation sequences during walking turns. Eyes led (407 ms prior to IFC1), followed by the head (50 ms prior to IFC1), then trunk and pelvis. In contrast, PD produced no anticipatory eye or segment movement at baseline. During pre-trials the eyes moved 96 ms after IFC1 and segment movement was initiated by the pelvis followed by trunk and head segments. After visual cue training however, PD produced anticipatory eye movements 161 ms prior to IFC1, followed by the head 88 ms following IFC1 but ahead of trunk and pelvis onset. These results suggest visual cues assist in producing cranio-caudal control during walking turns in PD.

Introduction The causes of falls and resultant head injuries in people with epilepsy are complex and represent important clinical issues significantly impacting on safety, quality of life and long-term prognosis. A general solution for many years has been to provide helmets for head protection. There is poor understanding of the influencing risk factors and solutions to give person-centred clinical advice. Methods A focused narrative review was conducted to investigate the risk factors for seizure-related head injuries and evidence of current helmets to offer protection. Four databases were searched (Embase, Medline, PsycInfo and Cochrane Library) using combinations of text words and thesaurus terms for the retrieval of articles relating to seizure-related head injury. Articles for full analysis were selected by a ten item pre-defined inclusion criteria. Results Of 104 relevant studies longlisted 21 studies met four or more of the predefined criteria and included in this review. A further nine papers were included because they added additional relevant information. Conclusions Seizure-related head injury, although rare, may have serious consequences. High doses of antiepileptic/antiseizure drugs (AEDs/ASDs) and a prescription for three or more AEDs/ASDs are significant, modifiable, risk factors for head injury. Differentiating confusion due to post-ictal changes or concussion can be challenging. Seizure-related cardiac causes leading to injury due to ictal bradycardia or asystole is under investigated. More research is required to validate the protective benefit of various helmet designs in seizure-related head injury. It is striking that there are no International Standards for protective helmets in seizures.

We present a dependency tree linearization model with two novel components: (1) a tree-structured encoder based on bidirectional Tree-LSTM that propagates information first bottom-up then top-down, which allows each token to access information from the entire tree; and (2) a linguistically motivated head-first decoder that emphasizes the central role of the head and linearizes the subtree by incrementally attaching the dependents on both sides of the head. With the new encoder and decoder, we reach state-of-the-art performance on the Surface Realization Shared Task 2018 dataset, outperforming not only the shared tasks participants, but also previous state-of-the-art systems (Bohnet et al., 2011; Puduppully et al., 2016). Furthermore, we analyze the power of the tree-structured encoder with a probing task and show that it is able to recognize the topological relation between any pair of tokens in a tree.

Fundamental safety measure for falling is to prepare flat and effective wide workplace with guardrails. However, their countermeasures may be difficult to apply for short-duration works and disaster relief works. In such cases, the fall arrest system has been applied to the height workplaces. This study focuses on fundamental characteristics of full body harness in various postures of wearer during falling. Three kinds of situation, such as (1) leg first fall, (2) head first fall, and (3) stop falling when the wearer body in parallel to the ground, were considered to recognize the performance. Experiments were carried out using 735N of human dummy, called HybridIII pedestrian 50%tile model in the automobile industry. The shock-absorber of the Lanyards used in this study were designed about 4 kN. Impact force acting on hook, head accelerations, and a chest displacement were measured during falling. From the results, not only the vertical acceleration of the human dummy but also horizontal were measured. Due to the horizontal acceleration, a huge bending moment acting on the dummy's neck observed in several situations. It indicates that the wearer may have risks of whiplash or more serious injuries such as dislocation of cervical vertebrae or spinal injuries. Chest deformations measured in this study were not also small for aged workers. It indicates that there are some risks of rid fractures or related chest injuries. The back of the head crashed aggressively to the D-ring of the full harness when the dummy rebounded due to stop falling by lanyard. Therefore, special helmet to resist the impact force due to D-ring, and the design force of shock-absorber should be reconsidered.

Background A rugby tackle is an open and unpredictable event, which can lead to intentional or unintentional head-first impacts rather than the preferred ‘shoulder first’ technique. Objective To identify the effect of head-neck orientation as well as collision speed on the loads experienced at the upper cervical spine and the relevance in terms of injury risk from head-first impacts. Design Repeated ‘tackles’ were simulated using a 40 kg punch bag (simulated ball carrier) making contact against a fixed instrumented head and neck anthropometric test device (ATD). Setting Biomechanics laboratory. Patients (or Participants) A single head-neck ATD was used to complete all the trials. Interventions (or Assessment of Risk Factors) 10 repetitions were recorded in each of two speed ranges (low and high) and 3 ATD sagittal plane orientations (head-up [+20°], neutral [0°], and head-down [-20°]), 60 trials in total. Main Outcome Measurements Forces experienced at the equivalent of the C1 vertebra were measured by a load cell at the head joint of the ATD. ANCOVA (covariate=punch bag speed) and effect sizes were used to assess differences between tackle conditions. Results Low speed (2.34±0.18 m/s) tackles resulted in 37% lower peak impact forces compared with high speed (3.43±0.17 m/s) tackles. Total force on neck acted in multiple directions (75% in compression; magnitude of total force was 2.37±0.18 kN in neutral high speed condition) and it was substantially higher in the head-down orientation compared with the neutral (13%) and head-up orientation (17%). Conclusions Our findings support the idea that: 1) collision speed during a tackle affects the load experienced by the head-neck structures; 2) a neutral or head-up orientation of the head is preferred to a head-down orientation in the event of head-first impacts during simulated rugby tackle, which aligns with current Rugby Union coaching recommendations.

Survival, in part, depends on an individual's ability to evade predators. In desert regions some lizard species have evolved head-first sand-diving strategies to escape predators. To facilitate this behaviour, a distinctive head morphology that facilitates sand-diving has evolved. This specialised head morphology may, however, come at a cost to other ecologically relevant functions, particularly bite force. Here, we investigated the relationship between morphology and function in a southern African lacertid lizard genus, Meroles, which consists of eight species that utilise different escape strategies, including sand-diving and running for cover. It was hypothesized that the specialised head morphology of diving species would negatively affect bite force capacity. We found that species from each escape strategy category differed significantly in head shape, but not bite force performance. A phylogenetic tree of the genus was constructed using two mitochondrial and two nuclear genes, and we conducted phylogenetic comparative analyses. One aspect of the head shape differed between the escape strategies once phylogeny was taken into account. We found that bite force may have co-evolved with head morphology, but that there was no trade-off between biting capacity and escape strategy in Meroles.

Optimum energy consumption in wireless sensitive networks plays an important role on network management. In the proposed model of this paper, first all the nods send the energy, station distance and density parameters to their fuzzy modules. According to each nod's fuzzy module outputs, a timer is activated for all nodes, which start reverse-counting from obtained value from fuzzy module. Timer of better nod comes to zero sooner and two best nods are selected in each zone (with the distance of r). One of them is introduced as superior cluster head and the other nods are connected to the closest cluster head. In addition, the cluster head not introduced as superior cluster head first collects data from neighbor's nods and then sends it to the superior cluster head after classifying data as package. The performance of the proposed model of this paper is compared with other methods and the preliminary results indicate that the proposed algorithm has increased first nod death time compared with other methods in the literature.

One of the challenges facing teachers is to develop students' ability to understand a problem, use this knowledge to find a solution, and then apply what they have learned to a real-world situation. The Ohio Academic Standards, as do many other states' standards, call for applying mathematical knowledge and skill in other content areas and practical situations (INFOhio 2007). The project described here—to determine the volume of water in Norris Lake, Tennessee—satisfies Ohio Academic Standards for computing various attributes, including area and volume, and for developing a mathematical model. It also addresses a specific, practical need: Knowing the volume of the lake is critical to managing the flow of water over the dam, generating electricity, and assessing the environmental impact on fish and wildlife. The project allows students to take what they have learned about calculating areas and volumes, using maps and scales, and incorporating the use of technology to approximate the total volume of water in Norris Lake.

Suprematism’s attempt to move beyond representation in painting coincided with an attempt to move beyond Russian Futurist poetry and literature. It was an attempt to go ‘beyond zero’. In making that move, however, Kasimir Malevich, creator of suprematism, needed to develop from Russian Futurism—particularly that of Velimir Khlebnikov— working within the Russian avant-garde. Through his painterly reliance on the square, Malevich not only worked in concert with Futurists such as Khlebnikov but ultimately elaborated on a literary theory bound by the constraints of language. In essence, Malevich’s Suprematism could not get ‘beyond zero’ until Khlebnikov’s Futurism got him there.

The objective of this experimental investigation was to find out what dynamic forces a bicycle helmet' retention system is subjected to when head impact accidents take place. Different helmet models were subjected to simulated accidents, of the type with the head first (with vertical and horizontal velocity) against a rigid asphalt surface. The chin strap forces developed in the accident simulations of the present study were low compared to the requirements of most of the existing standards for bicycle helmets. The arithmetic mean of the chin strap peak forces of all impacts was 42 N. Three types of helmets were investigated, one hard-shell helmet, one non-shell helmet and one ribbed helmet (large ventilation holes) with hard shell. A six-year-old child test dummy and a car-crash test facility with a piece of inclined asphalt road on the carriage were the main attributes of the study. The test dummy was suspended from the ceiling and was hit by the piece of asphalt road mounted on the stiff car-c...

No matter how hard I try, I cannot recall the moments just before I crashed on that September morning in 2007. It was my usual bike ride down the gravel path to work, when somehow, I fell, landing head first into the ground. A concerned jogger helped me down the hill, then my husband brought me to

Sperm competition favours an increase in sperm swimming velocity that maximises the chances that sperm will reach the ova before rival sperm and fertilise. Comparative studies have shown that the increase in sperm swimming speed is associated with an increase in total sperm size. However, it is not known which are the first evolutionary steps that lead to increases in sperm swimming velocity. Using a group of closely related muroid rodents that differ in levels of sperm competition, we here test the hypothesis that subtle changes in sperm design may represent early evolutionary changes that could make sperm swim faster. Our findings show that as sperm competition increases so does sperm swimming speed. Sperm swimming velocity is associated with the size of all sperm components. However, levels of sperm competition are only related to an increase in sperm head area. Such increase is a consequence of an increase in the length of the sperm head, and also of the presence of an apical hook in some of the species studied. These findings suggest that the presence of a hook may modify the sperm head in such a way that would help sperm swim faster and may also be advantageous if sperm with larger heads are better able to attach to the epithelial cells lining the lower isthmus of the oviduct where sperm remain quiescent before the final race to reach the site of fertilisation. © 2011 Society for Reproduction and Fertility.

We quantitatively analysed compensatory head reactions of flies to imposed body rotations in yaw, pitch and roll and characterized the haltere as a sense organ for maintaining equilibrium. During constant velocity rotation, the head first moves to compensate retinal slip and then attains a plateau excursion (Fig. 3). Below 500°/s, initial head velocity as well as final excursion depend linearily on stimulus velocities for all three axes. Head saccades occur rarely and are synchronous to wing beat saccades (Fig. 5). They are interpreted as spontaneous actions superposed to the compensatory reaction and are thus not resetting movements like the fast phase of ‘vestibulo-ocular’ nystagmus in vertebrates. In addition to subjecting the flies to actual body rotations we developed a method to mimick rotational stimuli by subjecting the body of a flying fly to vibrations (1 to 200 μm, 130 to 150 Hz), which were coupled on line to the fly's haltere beat. The reactions to simulated Coriolis forces, mimicking a rotation with constant velocity, are qualitatively and to a large extent also quantitatively identical to the reactions to real rotations (Figs. 3, 7–9). Responses to roll- and pitch stimuli are co-axial. During yaw stimulation (halteres and visual) the head performs both a yaw and a roll reaction (Fig. 3e,f), thus reacting not co-axial. This is not due to mechanical constraints of the neck articulation, but rather it is interpreted as an ‘advance compensation’ of a banked body position during free flight yaw turns (Fig. 10).

For CyberKnife planning and treatment, patients are set up on a thin foam pad. In the head first supine position, the patient's arms are at body level at their side for treatment. This position of the arms does not allow beams to be planned and delivered that transit the arms if arm avoidance is desired. To circumvent this problem, a new thicker, firmer patient support pad has been developed and used to treat many patients at our CyberKnife Centers. The new pad is narrower at the level of the trunk and abdomen allowing the patient's arms to fall comfortably below body level. This allows more beams to be planned using the plan optimization routine to enter the body from more posterior-lateral directions than can be obtained with the patient on the thin pad. Illustration of the use of the new pad and an example plan is discussed.

The patient was a 23-year-old woman referred to physical therapy for the primary treatment of knee pain which began 4 months prior following a twisting injury. During the patient interview, the patient also complained of neck pain and numbness and tingling in her bilateral hands and feet which began 6 weeks earlier after jumping into a 2 meter pool head first and striking her head on the floor of the pool. Due to concern over a serious cervical spine injury, the physical therapist focused his initial physical examination on the patient's cervical spine. Physical examination findings were remarkable for midline cervical spine tenderness and decreased sensation throughout both hands and feet. Cervical spine radiographs were ordered, which revealed a cortical irregularity along the anterior aspect of the superior endplate of the C7 vertebral body, which was concerning for an anterior-superior compression fracture. Computed tomography scanning was completed for further evaluate the area of injury and revealed...

Bungee jumping is a dangerous sport with increasing popularity in the western world. We report the case of a 28-yr-old man who sustained an orbital emphysema as a result of bungee jumping. He jumped head first from a 160-ft high bridge over a river. At the end of the jump he dived into the water with his head in a reclined position. The sudden dive into the water caused an increase of the air pressure in the nose and paranasal sinuses, which led to an emphysema of the right orbit resulting from a skull fracture not detectable by x-ray. The patient was treated with oral antibiotics. Five days later, he had no clinical complaints and the ophthalmologic examination was normal. This variation of bungee jumping may bear severe risk factors for health in addition to those known from the classic jumps. Language: en

The countermanding task requires subjects to cancel a planned movement on appearance of a stop signal, providing insights into response generation and suppression. Here, we studied human eye-head gaze shifts in a countermanding task with targets located beyond the horizontal oculomotor range. Consistent with head-restrained saccadic countermanding studies, the proportion of gaze shifts on stop trials increased the longer the stop signal was delayed after target presentation, and gaze shift stop-signal reaction times (SSRTs: a derived statistic measuring how long it takes to cancel a movement) averaged approximately 120 ms across seven subjects. We also observed a marked proportion of trials (13% of all stop trials) during which gaze remained stable but the head moved toward the target. Such head movements were more common at intermediate stop signal delays. We never observed the converse sequence wherein gaze moved while the head remained stable. SSRTs for head movements averaged approximately 190 ms or approximately 70-75 ms longer than gaze SSRTs. Although our findings are inconsistent with a single race to threshold as proposed for controlling saccadic eye movements, movement parameters on stop trials attested to interactions consistent with a race model architecture. To explain our data, we tested two extensions to the saccadic race model. The first assumed that gaze shifts and head movements are controlled by parallel but independent races. The second model assumed that gaze shifts and head movements are controlled by a single race, preceded by terminal ballistic intervals not under inhibitory control, and that the head-movement branch is activated at a lower threshold. Although simulations of both models produced acceptable fits to the empirical data, we favor the second alternative as it is more parsimonious with recent findings in the oculomotor system. Using the second model, estimates for gaze and head ballistic intervals were approximately 25 and 90 ms, respectively, consistent with the known physiology of the final motor paths. Further, the threshold of the head movement branch was estimated to be 85% of that required to activate gaze shifts. From these results, we conclude that a commitment to a head movement is made in advance of gaze shifts and that the comparative SSRT differences result primarily from biomechanical differences inherent to eye and head motion.

We quantitatively analysed compensatory head reactions of flies to imposed body rotations in yaw, pitch and roll and characterized the haltere as a sense organ for maintaining equilibrium. During constant velocity rotation, the head first moves to compensate retinal slip and then attains a plateau excursion (Fig. 3). Below 500 ° /s, initial head velocity as well as final excursion de- pend linearily on stimulus velocities for all three axes. Head saccades occur rarely and are synchronous to wing beat saccades (Fig. 5). They are interpreted as spontane- ous actions superposed to the compensatory reaction and are thus not resetting movements like the fast phase ol `vestibulo-ocular' nystagmus in vertebrates. In addition to subjecting the flies to actual body rotations we developed a method to mimick rotational stimuli by subjecting the body of a flying fly to vibrations (1 to 200 µm, 13C to 150 Hz), which were coupled on line to the fly's haltere beat. The reactions to simulated Coriolis forces, mimicking a rotation with constant velocity, are qualita- tively and to a large extent also quantitatively identical tc the reactions to real rotations (Figs. 3, 7-9). Response, to roll- and pitch stimuli are co-axial. During yaw stimu- lation (halteres and visual) the head performs both a yam and a roll reaction (Fig. 3e,f), thus reacting not co-axial This is not due to mechanical constraints of the neck ar- ticulation, but rather it is interpreted as anadvance com- pensation' of a banked body position during free flight yaw turns (Fig. 10).

Wrist and hand injuries are common in elite divers, as all correctly performed dives end with a head first entry into the water with the hands extended above the head. This case presentation was an Olympic level diver with 3 months of persistent dorsal wrist pain. MRI findings showed contiguous contusions to the lunate, capitate, hamate and distal radius and also a peripheral tear of the ulnar attachment of the triangular fibrocartilage complex (TFCC). The repeated dorsiflexion stress of entry into the water likely caused these injuries. Although the authors had suspected a TFCC injury and did find an isolated ulnar-sided peripheral tear, the complicating carpal contusions led us to choose a conservative treatment plan, which was the only intervention the patient ultimately required.

The walking step of the microtubule minus-end directed kinesin motor Ncd involves about 75-degree rotation of its coiled-coil stalk. Two crystal structures, 1CZ7 and 1N6M (protein data bank IDs) are related respectively to conformations before (plus-end pointing stalk) and after (minus-end pointing stalk) this movement. Using targeted molecular dynamics we traced the stalk motion between these two structures. We observed that the motor head first rearranges from the 1CZ7 to 1N6M conformation, followed by the travel of the stalk. The 75-degree rotation of the stalk is accompanied by a nearly 20-degree torsion in its coiled coil. Further, the stalk travel can be divided into sub-steps between intermediates at about 17, 38 and 56 degrees from the 1CZ7 conformation that are characterized by the breaking and forming of new salt bridges by Arg335 or Lys336 in the stalk with the charged groups along the alpha-1 domain of the motor head, some of which are not present in the crystal structures. These results suggest that when Ncd is making a step towards the microtubule minus-end, the motor head first changes conformation in a nucleotide-dependent manner that promotes the detachment of the plus-end pointing stalk. This is followed by the stalk rotation that may be broken down into sub-steps between the intermediate states. In case of a diffusive motion, this may be more effective than diffusion over the entire 75-degree range.

PALEONTOLOGYThe most primitive tyrannosauroid yet discovered, described this week in Nature , has revealed the basic blueprint from which Tyrannosaurus rex and its kin evolved.

Science just ran head first into religion in the form of putative human clones. The mere existence of such clones marks a societal turning point; the full ramifications will take years to map. Immediately apparent was the irritation of the religious and public policy communities. Both had large stakes in fashioning generally-acceptable outcomes; it is unlikely that this is the result they envisioned. Theologians feel especially betrayed, with good reason: dialogues between science and religion were leading to some sense that each side was beginning to understand the other. Although this is unlikely to be a fatal setback to such dialogues, it might reasonably make the religion end of the science-religion axis somewhat suspicious of the motives of the science end. I can imagine a work like John C Avise's Genetic Gods being dismissed, at least temporarily, as just-another-scientist's view of religion.

Toby Briant-Evans goes skiing, improves his language skills, and stitches scalps back together

Montevallo, Ala., Aug. 6, 1898. To the Editor: —I wish to mention the case of a negro girl whom I delivered of twins, Feb. 5, 1897. This girl was born and raised in Boiling, Ala. At 11 years of age, she began to menstruate regularly; became a prostitute soon afterward, and was delivered of twins at the age of 13 years, 9 months and 5 days. Both children were females. One is living; the other was accidentally smothered when five days old. The first child presented feet foremost; the second came "head first." The afterbirth was adherent. I administered chloroform and, after introducing the hand, detached it. There was some hemorrhage, but a hot douche controlled it. The mother was exceedingly well developed for her age and made a speedy recovery. I inclose a copy of the birth certificate. Very truly yours

HAVING occasionally caught a viper, and kept it for a time in a glass case, one of the platelayers called me last Thursday and said “there was a fine ‘Long Cripple’ (a local name for a serpent of any kind) lying on the bank a few yards down the line.” I went to the place indicated, and there was a very large viper basking in the sun, but when I got near, it began to move away, and to prevent its escape I gently pressed a stick across it while I sent the man to fetch a glass jar to secure it in; but when it found its progress arrested, it began in a very spiteful manner to dart its nose forward, striking at the stick and stones and anything that was within its reach, but I could not see that it opened its mouth to make a real bite; but when it found with all its wriggling and twisting it was unable to free itself, it turned its head round upon itself, and about four inches from the head it opened its jaws and gave itself a bite, and when the fangs were well into the skin, it gave an extra squeeze, as if it intended to make sure that the operation should be thoroughly and effectively performed. It then deliberately withdrew its fangs, and in so doing it turned its head first one way and then the other, so as to withdraw one fang at a time.

We developed a simple method to confine ducks so that a person working alone would be able to take blood samples from the brachial vein of a bird's extended wing. A piece of polychlorinated vinyl (PCV) pipe about 30 cm long was slotted about half way from the end to accommodate the bird's extended wing; the slot was about 12 mm wide. Sleeves of 2 sizes were made, one of 7.5-cm diameter pipe to accommodate blue-winged teals (Anas discors) and another of 11.5-cm diameter for lesser scaups (Aythya affinis) and similar-sized ducks. A larger sleeve, 12.6 cm in diameter, would be useful for larger ducks such as mallards (Anas platyrhynchos), although we did utilize the 11.5-cm sleeve for 10 canvasbacks (Aythya valisineria) without much difficulty. Each duck was inserted head first into

Patient. —E. P., white, aged 13, a schoolboy, was admitted to Kansas City Post-Graduate Hospital, Nov. 23, 1908. Previous History. —The patient stated that on the night of Nov. 19, 1908, in attempting to remove an accumulation of dirt or foreign matter from the glans penis, he had passed a shawlpin head first into the urethra, and it had slipped away from his grasp and become fastened in the urethra. He denied sexual perversion. Present Condition. —The boy is well nourished and well-developed. Intellectually, he seems below normal and has a peculiar defect in speech, something between a lisp and a stammer. He complains of nothing referable to bladder or otherwise, and passes urine without difficulty. He was brought to the hospital by his father because the boy had told him of losing the pin in his urethra, not because of any particular discomfort caused by the foreign body. Examination